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1. A comprehensive review of carbon capture science and technologies

Author

Wu, C, Huang, Q, Xu, Z, Sipra, AT, Gao, N, Vandenberghe, LPDS, Vieira, S, Soccol, CR, Zhao, R, Deng, S, Boetcher, SKS, Lu, S, Shi, H, Zhao, D, Xing, Y, Chen, Y, Zhu, J, Feng, D, Zhang, Y, Deng, L, Hu, G, Webley, PA, Liang, D, Ba, Z, Mlonka-Medrala, A, Magdziarz, A, Miskolczi, N, Tomasek, S, Lam, SS, Foong, SY, Ng, HS, Jiang, L, Yan, X, Liu, Y, Ji, Y, Sun, H, Yang, H, Zhang, X, Sun, M, Tsang, DCW, Shang, J, Muller, C, Rekhtina, M, Krodel, M, Bork, AH, Donat, F, Liu, L, Jin, X, Liu, W, Saqline, S, Wu, X, Xu, Y, Khan, AL, Ali, Z, Lin, H, Hu, L, Huang, J, Singh, R, Wang, K, He, X, Dai, Z, Yi, S, Konist, A, Baqain, MHS, Zhao, Y, Sun, S, Chen, G, Tu, X, Weidenkaff, A, Kawi, S, Lim, KH, Song, C, Yang, Q, Zhao, Z, Gao, X, Jiang, X, Ji, H, Akinola, TE, Lawal, A, Otitoju, OS, Wang, M, Zhang, G, Ma, L, Sempuga, BC, Liu, X, Oko, E, Daramola, M, Yu, Z, Chen, S, Kang, G, Li, Q, Gao, L, Zhou, H, Wu, C, Huang, Q, Xu, Z, Sipra, AT, Gao, N, Vandenberghe, LPDS, Vieira, S, Soccol, CR, Zhao, R, Deng, S, Boetcher, SKS, Lu, S, Shi, H, Zhao, D, Xing, Y, Chen, Y, Zhu, J, Feng, D, Zhang, Y, Deng, L, Hu, G, Webley, PA, Liang, D, Ba, Z, Mlonka-Medrala, A, Magdziarz, A, Miskolczi, N, Tomasek, S, Lam, SS, Foong, SY, Ng, HS, Jiang, L, Yan, X, Liu, Y, Ji, Y, Sun, H, Yang, H, Zhang, X, Sun, M, Tsang, DCW, Shang, J, Muller, C, Rekhtina, M, Krodel, M, Bork, AH, Donat, F, Liu, L, Jin, X, Liu, W, Saqline, S, Wu, X, Xu, Y, Khan, AL, Ali, Z, Lin, H, Hu, L, Huang, J, Singh, R, Wang, K, He, X, Dai, Z, Yi, S, Konist, A, Baqain, MHS, Zhao, Y, Sun, S, Chen, G, Tu, X, Weidenkaff, A, Kawi, S, Lim, KH, Song, C, Yang, Q, Zhao, Z, Gao, X, Jiang, X, Ji, H, Akinola, TE, Lawal, A, Otitoju, OS, Wang, M, Zhang, G, Ma, L, Sempuga, BC, Liu, X, Oko, E, Daramola, M, Yu, Z, Chen, S, Kang, G, Li, Q, Gao, L, and Zhou, H

Published
2024

3. Comprehensive review of environmental factors influencing the performance of photovoltaic panels: Concern over emissions at various phases throughout the lifecycle.

Author

Jathar, LD, Ganesan, S, Awasarmol, U, Nikam, K, Shahapurkar, K, Soudagar, MEM, Fayaz, H, El-Shafay, AS, Kalam, MA, Bouadila, S, Baddadi, S, Tirth, V, Nizami, AS, Lam, SS, Rehan, M, Jathar, LD, Ganesan, S, Awasarmol, U, Nikam, K, Shahapurkar, K, Soudagar, MEM, Fayaz, H, El-Shafay, AS, Kalam, MA, Bouadila, S, Baddadi, S, Tirth, V, Nizami, AS, Lam, SS, and Rehan, M

Abstract

Recently, solar photovoltaic (PV) technology has shown tremendous growth among all renewable energy sectors. The attractiveness of a PV system depends deeply of the module and it is primarily determined by its performance. The quantity of electricity and power generated by a PV cell is contingent upon a number of parameters that can be intrinsic to the PV system itself, external or environmental. Thus, to improve the PV panel performance and lifetime, it is crucial to recognize the main parameters that directly influence the module during its operational lifetime. Among these parameters there are numerous factors that positively impact a PV system including the temperature of the solar panel, humidity, wind speed, amount of light, altitude and barometric pressure. On the other hand, the module can be exposed to simultaneous environmental stresses such as dust accumulation, shading and pollution factors. All these factors can gradually decrease the performance of the PV panel. This review not only provides the factors impacting PV panel's performance but also discusses the degradation and failure parameters that can usually affect the PV technology. The major points include: 1) Total quantity of energy extracted from a photovoltaic module is impacted on a daily, quarterly, seasonal, and yearly scale by the amount of dust formed on the surface of the module. 2) Climatic conditions as high temperatures and relative humidity affect the operation of solar cells by more than 70% and lead to a considerable decrease in solar cells efficiency. 3) The PV module current can be affected by soft shading while the voltage does not vary. In the case of hard shadowing, the performance of the photovoltaic module is determined by whether some or all of the cells of the module are shaded. 4) Compared to more traditional forms of energy production, PV systems offer a significant number of advantages to the environment. Nevertheless, these systems can procure greenhouse gas emissions, e

Published
2023

4. Applications of nanotechnology in biodiesel combustion and post-combustion stages

Author

Hosseinzadeh-Bandbafha, H, Kazemi Shariat Panahi, H, Dehhaghi, M, Orooji, Y, Shahbeik, H, Mahian, O, Karimi-Maleh, H, Kalam, MA, Salehi Jouzani, G, Mei, C, Nizami, AS, Guillemin, GG, Gupta, VK, Lam, SS, Yang, Y, Peng, W, Pan, J, Kim, KH, Aghbashlo, M, Tabatabaei, M, Hosseinzadeh-Bandbafha, H, Kazemi Shariat Panahi, H, Dehhaghi, M, Orooji, Y, Shahbeik, H, Mahian, O, Karimi-Maleh, H, Kalam, MA, Salehi Jouzani, G, Mei, C, Nizami, AS, Guillemin, GG, Gupta, VK, Lam, SS, Yang, Y, Peng, W, Pan, J, Kim, KH, Aghbashlo, M, and Tabatabaei, M

Abstract

Diesel fuel exhibits high efficiency, durability, and profitability for combustion engines but remains a major source of airborne pollutants, including particulate matter and nitrogen oxides. To address the urgent need for alternative energy sources and reduce greenhouse gas emissions, biodiesel has been developed as a potential replacement for petrodiesel. However, biodiesel combustion has its drawbacks, especially the emission of nitrogen oxides, which hinder its ability to replace petrodiesel sustainably. Nanotechnology has been proposed as a promising solution to improve biodiesel combustion and enhance its competitiveness against petrodiesel. Various studies have shown that both metallic and non-metallic nanoparticles can potentially enhance biodiesel performance during combustion, improving fuel combustion efficiency by 11.7% and 13.4% while reducing air pollutants such as carbon monoxide by 24.2% and 24.8% and unburned hydrocarbons by 11.5% and 25.3%, respectively. While both types of nanoparticles can potentially reduce greenhouse gas and particulate matter emissions, their impact on nitrogen oxide emissions varies. Non-metallic nanoparticles are more successful in reducing nitrogen oxide emissions, achieving reductions of up to 13.0%, while metallic nanoparticles have been shown to increase nitrogen oxides by 0.8% on average. In the post-combustion phase, nanoparticles can filter pollution from diesel engines with more than 99% efficiency, reducing friction, enhancing engine durability, preventing deposit formation, and reducing maintenance costs. However, using nanoparticles in biodiesel has several drawbacks, including toxicity to humans and ecosystems, high prices, lack of standardization, and limited understanding of their long-term effects. Further research is needed to address these constraints and ensure the safe and effective use of nanoparticles in biodiesel combustion. The potential benefits of nanotechnology for improving biodiesel combustion and

Published
2023

5. Integrated Biorefinery Design with Techno-Economic and Life Cycle Assessment Tools in Polyhydroxyalkanoates Processing

Author

Universitat Rovira i Virgili, Andhalkar, VV; Foong, SY; Kee, SH; Lam, SS; Chan, YH; Djellabi, R; Bhubalan, K; Medina, F; Constanti, M, Universitat Rovira i Virgili, and Andhalkar, VV; Foong, SY; Kee, SH; Lam, SS; Chan, YH; Djellabi, R; Bhubalan, K; Medina, F; Constanti, M

Abstract

To support and move toward a sustainable bioeconomy, the production of polyhydroxyalkanoates (PHAs) using renewable biomass has acquired more attention. However, expensive biomass pretreatment and low yield of PHAs pose significant disadvantages in its large-scale production. To overcome such limitations, the most recent advances in metabolic engineering strategies used to develop high-performance strains that are leading to a new manufacturing concept converting biomass to PHAs with co-products such as amino acids, proteins, biohydrogen, biosurfactants, and various fine chemicals are critically summarized. This review article presents a comprehensive roadmap that highlights the integrated biorefinery strategies, lifecycle analysis, and techno-economic assessment for sustainable and economic PHAs production. Finally, current and future challenges that must be addressed to transfer this technology to real-world applications are reviewed.

Published
2023

6. Microwave-assisted pyrolysis technology for bioenergy recovery: Mechanism, performance, and prospect

Author

Su, G, Ong, HC, Cheah, MY, Chen, WH, Lam, SS, and Huang, Y

Subjects
Energy, 0306 Physical Chemistry (incl. Structural), 0904 Chemical Engineering, 0913 Mechanical Engineering
Abstract

The emergence of bioenergy provides a solution to the environment and energy crises caused by the indiscriminate use of fossil fuels. Pyrolysis technology has broad application prospects in bioenergy production and waste disposal, providing a solid guarantee for the sustainable development of human beings and the environment. As an endothermic process, pyrolysis relies on external heat as an energy source. The introduction of microwave provides a different energy source for the pyrolysis process and exhibits a different pyrolysis performance due to its unique energy transfer mechanism. Conventional pyrolysis is conducive to the formation of bio-oil, whereas microwave-assisted pyrolysis can improve the composition of bio-oil and the surface properties of biochar. This article focuses on the advantages and limitations of microwave-assisted and conventional pyrolysis modes. Special attention is given to the differences in product distribution and properties and the economic feasibility of the two pyrolysis modes.

Published
2022

8. Removal of persistent acetophenone from industrial waste-water via bismuth ferrite nanostructures

Author

Irfan, S, Khan, SB, Lam, SS, Ong, HC, Aizaz Ud Din, M, Dong, F, and Chen, D

Subjects
Light, Meteorology & Atmospheric Sciences, Acetophenones, Industrial Waste, Water, Wastewater, Bismuth, Ferric Compounds, Environmental Sciences, Catalysis, Nanostructures
Abstract

Increasing water pollution is a severe problem in densely industrialized countries. Nanomaterials provide strong potentials for the efficient elimination of organic pollutants due to their beneficial properties. Advancement in water purification is required to more efficiently remove the emerging organic contaminants, especially in pharmaceuticals wastes such as acetophenone, which shows high solubility in industrial wastewaters. Bismuth ferrite-based nanostructures were fabricated using a novel double solvent sol-gel method. The phase purity and crystallinity of bismuth ferrite were confirmed using XRD and further endorsed by TEM analysis. The SEM and XPS were used to study the particle sizes and presence of co-dopants on the Bi and Fe-sites of bismuth ferrite. After co-doping, the band-gap engineering of pure bismuth ferrites was accomplished by reducing it from 2.06 eV to 1.45 eV, likely attributing to the creation of shallow traps for the incoming photo-generated charge carriers. In particular, the Bi0.90Gd0.10Fe0.95Sn0.05 and Bi0.95Sm0.05Fe0.75Mn0.25 successfully eliminated up to 98% of acetophenone from polluted water in 3 h by irradiation of visible-light. These results reveal the suitability of the co-doped bismuth ferrites photocatalysts for the practical removal of pharmaceutical contaminants in hazardous industrial wastewater. The photodegradation of acetophenone by bismuth ferrite nanostructures with potentially long-lasting reusability demonstrate its potential as an advanced photocatalyst for wastewater treatment.

Published
2022

9. Sustainable hydrogen production: Technological advancements and economic analysis

Author

Ahmed, SF, Mofijur, M, Nuzhat, S, Rafa, N, Musharrat, A, Lam, SS, Boretti, A, Ahmed, SF, Mofijur, M, Nuzhat, S, Rafa, N, Musharrat, A, Lam, SS, and Boretti, A

Abstract

Hydrogen (H2) is pivotal to phasing out fossil fuel-based energy systems. It can be produced from different sources and using different technologies. Very few studies comprehensively discuss all available state-of-the-art technologies for H2 production, the challenges facing each process, and their economic feasibility and sustainability. The current study thus addresses these gaps to effectively direct future research towards improving H2 production techniques. Many conventional methods contribute to large greenhouse gas footprints, with high production costs and low efficiency. Steam methane reforming and coal gasification dominate the supply side of H2, due to their low production costs (<$3.50/kg). Water-splitting offers one of the most environmentally benign production methods when integrated with renewable energy sources. However, it is considerably expensive and ridden with the flaw of production of harmful by-products that affect efficiency. Fossil fuel processing technologies remain one of the most efficient forms of H2 production sources, with yields exceeding 80% and reaching up to 100%, with the lowest cost despite their high reliance on expensive catalysts. Whereas solar-driven power systems cost slightly less than $10 kg−1, coal gasification and steam reforming cost below $3.05 kg−1. Future research thus needs to be directed towards cost reduction of renewable energy-based H2 production systems, as well as in their decarbonization and designing more robust H2 storage systems that are compatible with long-distance distribution networks with adequate fuelling stations.

Published
2022

10. Recent advancement in deoxygenation of fatty acids via homogeneous catalysis for biofuel production

Author

Tabandeh, M, Cheng, CK, Centi, G, Show, PL, Chen, WH, Ling, TC, Ong, HC, Ng, EP, Juan, JC, Lam, SS, Tabandeh, M, Cheng, CK, Centi, G, Show, PL, Chen, WH, Ling, TC, Ong, HC, Ng, EP, Juan, JC, and Lam, SS

Abstract

© 2020 Elsevier B.V. Fuel-like hydrocarbons (also known as biofuel) isolated from the deoxygenation of fatty acids present different advantages as compared with fossil fuels. In particular, the homogeneous and heterogeneous catalytic deoxygenation methods have been the center of attention during recent years. Although catalytic deoxygenation of fatty acids via heterogeneous catalysis has been widely investigated, there is a high demand to review the progress in using the homogeneous catalysis pathways. Among the various homogeneous pathways, radical-based reactions and transition metal catalysis demonstrate the most promising results in the decarboxylation and decarbonylation processes. It is shown that radical-based reactions are more active in decarboxylation meanwhile the transition metal catalysts are rather selective to decarbonylation of fatty acids. Besides, the reaction conditions and type of catalysts are capable of enhancing biofuel production. Homogenous catalysis provides the huge potential for commercializing viability of biofuel via deoxygenation of fatty acids.

Published
2022

11. Generating alternative fuel and bioplastics from medical plastic waste and waste frying oil using microwave co-pyrolysis combined with microbial fermentation

Author

Wan Mahari, WA, Kee, SH, Foong, SY, Amelia, TSM, Bhubalan, K, Man, M, Yang, YF, Ong, HC, Vithanage, M, Lam, SS, Sonne, C, Wan Mahari, WA, Kee, SH, Foong, SY, Amelia, TSM, Bhubalan, K, Man, M, Yang, YF, Ong, HC, Vithanage, M, Lam, SS, and Sonne, C

Abstract

In the present study, microwave co-pyrolysis (MCP) was used to simultaneously convert medical plastic waste (MPW) and waste frying oil (WFO) into liquid oil products. The MCP process demonstrated a faster heating rate (24 °C/min) and shorter process time (20 min) compared to conventional pyrolysis techniques converting MPW and WFO into liquid oil (≥80 wt%). The MCP reduced the oxygen content from 25.7 to 9.82 wt% in liquid oil encompassing light aliphatic hydrocarbons ranging from C10 to C28, generating a novel sustainable liquid fuel. The liquid having a high carbon content (approximately 77.1 wt%) and low carbon to nitrogen ratio (27.9) is a suitable energy feedstock for polyhydroxyalkanoate (PHA) bioplastic production in the form of poly3-hydroxybutyrate [P(3HB)]. The liquid oil acted as an energy source for the growth of Bacillus sp. During microbial fermentation, yielding approximately 11% (w/w) P(3HB). Bioplastics are biodegradable, biocompatible with humans and non-toxic to marine organisms, representing a valuable additive in the production of cosmetics, detergents, and as medical scaffolds for tissue engineering. The results indicate the promising upcycling of waste products by this approach through pyrolytic biorefinery into value-added fuel and bioplastic products, being important for the future sustainable production of renewable resources.

Published
2022

13. Bioenergy recovery potential through the treatment of the meat processing industry waste in Australia

Author

Mofijur, M, Fattah, IMR, Kumar, PS, Siddiki, SYA, Rahman, SMA, Ahmed, SF, Ong, HC, Lam, SS, Badruddin, IA, Khan, TMY, and Mahlia, TMI

Subjects
0306 Physical Chemistry (incl. Structural), 0904 Chemical Engineering, 0907 Environmental Engineering
Abstract

The farm animal and meat processing industry generate waste, including manure, fat, blood, sludge, bones, and wastewater, which create environmental problems worldwide. The effluents generated by this industry are rich in proteins, lipids, fibres, and carbohydrates. All these pollutants have the potential to be used as a resource for energy recovery. The organic matters obtained from the farm animal and meat processing industry are critical sources for biogas production via anaerobic digestion. This process leads to the production of energy-rich biogas, reducing greenhouse gas emissions. This study attempts to determine biogas amount and the energy value produced from the farm animal and meat processing industry in Australia. Australia's livestock population mainly consists of dairy cattle, meat cattle, sheep and lambs, pigs, layers, and meat chickens. Results show a potential biogas amount of 23,874,165 million m3 (Mm3), 215,670 Mm3, 288,228 Mm3, 18,430 Mm3, and 392,284 Mm3 can be obtained from cattle, lamb, sheep, pig, and poultry annually, respectively. The methane generated from slaughterhouse waste and wastewater is estimated to provide 4.52E+ 14 MJ/yr of heat energy with total electricity generation potential from livestock wastes of 4.4E+ 13 kWh/yr. About half of the electricity can be generated in Queensland State. Finally, the present study suggests farm animal and meat processing industry effluent as a potential sustainable energy source in Australia.

Published
2021

14. Theoretical calculation of biogas production and greenhouse gas emission reduction potential of livestock, poultry and slaughterhouse waste in Bangladesh

Author

Siddiki, SYA, Uddin, MN, Mofijur, M, Fattah, IMR, Ong, HC, Lam, SS, Kumar, PS, Ahmed, SF, Siddiki, SYA, Uddin, MN, Mofijur, M, Fattah, IMR, Ong, HC, Lam, SS, Kumar, PS, and Ahmed, SF

Abstract

The utilisation of available renewable resources and mitigating their impact on the environment boosts sustainable development and helps to achieve the United Nations Sustainable Development Goals. Biogas is a renewable energy option produced through anaerobic digestion of wastes such as livestock excreta and slaughterhouse wastes. Biogas production is treated as one of the leading processes to combat climate change as well as a waste management strategy, especially for a developing country like Bangladesh. It is also vital in meeting future demand for energy utilising indigenous sources. Livestock farming is an important economic activity in rural areas of Bangladesh. Thus, the livestock waste production, estimated biogas generation capacity, electricity generation potential, greenhouse gas (GHG) reduction potential, and estimated biofertiliser generation capacity of Bangladesh were determined for the financial year 2018-2019 in this study. The results show that Bangladesh had 486.77 million tons per year of animal waste products to produce 27,923.72 million m3/year biogas in 2018-2019. This biogas potential corresponds to a theoretical potential to produce a 512 PJ/year heating value and electric power of 50 TW h/year. Besides, about 29.232 million tons per year of organic fertiliser can be produced with the residues of the biogas plants. The findings of this study will contribute to guiding policymakers and governments who will concentrate on the use of animal waste in biogas industries and livestock farming as a potential bioenergy source to meet national energy demand.

Published
2021

15. Vertical flow constructed wetlands using expanded clay and biochar for wastewater remediation: A comparative study and prediction of effluents using machine learning

Author

Nguyen, XC, Ly, QV, Peng, W, Nguyen, V-H, Nguyen, DD, Tran, QB, Huyen Nguyen, TT, Sonne, C, Lam, SS, Ngo, HH, Goethals, P, Le, QV, Nguyen, XC, Ly, QV, Peng, W, Nguyen, V-H, Nguyen, DD, Tran, QB, Huyen Nguyen, TT, Sonne, C, Lam, SS, Ngo, HH, Goethals, P, and Le, QV

Abstract

This study evaluated and compared the performance of two vertical flow constructed wetlands (VF) using expanded clay (VF1) and biochar (VF2), of which both are low-cost, eco-friendly, and exhibit potentially high adsorption as compared to conventional filter layers. Both VFs achieved relatively high removal for organic matters (i.e. Biological oxygen demand during 5 days, BOD5) and nitrogen, accounting for 9.5 - 10.5 g.BOD5.m-2.d-1 and 3.5 - 3.6 g.NH4-N.m-2.d-1, respectively. The different filter materials did not exert any significant discrepancy to effluent quality in terms of suspended solids, organic matters and NO3-N (P > 0.05), but they did influence NH4-N effluent as evidenced by the removal rate of that by VF1 and VF2 being of 82.4 ± 5.7 and 84.6 ± 6.4%, respectively (P < 0.05). The results obtained from the designed systems were further subject to machine learning to clarify the effecting factors and predict the effluents. The optimal algorithms were random forest, generalized linear model, and support vector machine. The values of the coefficient of determination (R2) and the root mean square error (RMSE) of whole fitting data achieved 74.0% and 5.0 mg.L-1, 80.0% and 0.3 mg.L-1, 90.1% and 2.9 mg.L-1, and 48.5% and 0.5 mg.L-1 for BOD5_VF1, NH4-N_VF1, BOD5_VF2, and NH4-N_VF2, respectively.

Published
2021

16. Progress in the torrefaction technology for upgrading oil palm wastes to energy-dense biochar: A review

Author

Yek, PNY, Cheng, YW, Liew, RK, Wan Mahari, WA, Ong, HC, Chen, WH, Peng, W, Park, YK, Sonne, C, Kong, SH, Tabatabaei, M, Aghbashlo, M, Lam, SS, Yek, PNY, Cheng, YW, Liew, RK, Wan Mahari, WA, Ong, HC, Chen, WH, Peng, W, Park, YK, Sonne, C, Kong, SH, Tabatabaei, M, Aghbashlo, M, and Lam, SS

Abstract

The growing health and environmental concerns associated with the consumption of fossil energy sources catalyze the production of biofuels as renewable energy carriers for heat and electricity generation. Production of biofuels from biomass, being the most available renewable feedstock, is advantageous as it results in increased mitigation of GHGs (greenhouse gas) emissions. Co-firing biomass pellet in power plants is a promising way of using biomass for renewable energy generation. Among the various thermochemical conversion routes, torrefaction represents an efficient low-temperature pyrolysis technology to produce co-firing biofuel at 200–300 °C with low conversion losses. However, the current practice of using conventional heating in batch operation adversely affects oil palm torrefaction, leading to low throughput, low biomass processing rate, and poor heat transfer rate. Integration of microwave technology has emerged as a promising solution to enhance the upscaling capacity of torrefaction technology, offering higher production rates and better volumetric heat transfer. The present work critically reviews and discusses the latest developments in the torrefaction of oil palm waste to produce energy-dense biochar with reduced moisture content (for better water resistivity and durability). The use of microwave radiation as a heating method could also catalyze the torrefaction reaction with lower activation energy. In conclusion, microwave systems incorporated into continuous reactors seem to have great potential in streamlining torrefaction processes, thereby producing environmentally friendly energy.

Published
2021

17. Catalytic level identification of ZSM-5 on biomass pyrolysis and aromatic hydrocarbon formation

Author

Chen, W-H, Cheng, C-L, Lee, K-T, Lam, SS, Ong, HC, Ok, YS, Saeidi, S, Sharma, AK, and Hsieh, T-H

Subjects
Meteorology & Atmospheric Sciences, Environmental Sciences
Abstract

Zeolite socony mobil-5 (ZSM-5) is a common catalyst used for biomass pyrolysis. Nevertheless, the quantitative information on the catalytic behavior of ZSM-5 on biomass pyrolysis is absent so far. This study focuses on the catalytic pyrolysis phenomena and mechanisms of biomass wastes using ZSM-5 via thermogravimetric analyzer and pyrolysis-gas chromatography/mass spectrometry, with particular emphasis on catalytic level identification and aromatic hydrocarbons (AHs) formation. Two biomass wastes of sawdust and sorghum distillery residue (SDR) are investigated, while four biomass-to-catalyst ratios are considered. The analysis suggests that biomass waste pyrolysis processes can be divided into three zones, proceeding from a heat-transfer dominant zone (zone 1) to catalysis dominant zones (zones 2 and 3). The indicators of the intensity of difference (IOD), catalytic effective area, catalytic index (CI), and aromatic enhancement index are conducted to measure the catalytic effect of ZSM-5 on biomass waste pyrolysis and AHs formation. The maximum IOD occurs in zone 2, showing the highest intensity of the catalytic effect. The CI values of the two biomass wastes increase with increasing the biomass-to-catalyst ratio. However, there exists a threshold for sawdust pyrolysis, indicating a limit for the catalytic effect on sawdust. The higher the catalyst addition, the higher the AHs proportion in the vapor stream. When the biomass-to-catalyst ratio is 1/10, AHs formation is intensified significantly, especially for sawdust. Overall, the indexes conducted in the present study can provide useful measures to identify the catalytic pyrolysis dynamics and levels.

Published
2020

18. Microwave pyrolysis for valorisation of horse manure biowaste

Author

Mong, GR, Chong, CT, Ng, JH, Chong, WWF, Lam, SS, Ong, HC, and Ani, FN

Subjects
Energy, 0906 Electrical and Electronic Engineering, 0913 Mechanical Engineering
Abstract

© 2020 Elsevier Ltd Biomass-based feedstock is an attractive alternative to fossil fuel due to its sustainability and potential as a clean energy source. The present work focuses on the valorisation of horse manure biowaste to produce bioenergy via microwave-assisted pyrolysis technique. The thermal decomposition process is conducted by considering the effects of pyrolysis temperature, catalyst loading and carrier gas flow rate on the yield and quality of end products. The pyrolysed gaseous product contains up to 73.1 vol% of syngas components. The solid biochar obtained contains a heating value of 35.5 MJ/kg with high surface to pore volume ratio. The relatively high specific energy contents of gaseous products and biochar indicate their potential as biofuels. The liquid product is found to contain oxygenated phenolic compound of up to 79.4 wt%. In spite of an overall energy deficit achieved when comparing the total energy of end products with the feedstock, the energy balance analysis indicates the optimum production parameters. The least energy deficit is achieved at the reactive conditions of 350–450 °C and manure-to-catalyst ratio of 1:1. A reaction mechanism pathway for the pyrolysis of horse manure is presented to show the production route for bioenergy and valuable chemicals.

Published
2020

19. Recovery of diesel-like fuel from waste palm oil by pyrolysis using a microwave heated bed of activated carbon

Author

Lam, SS, Wan Mahari, WA, Cheng, CK, Omar, R, Chong, CT, Chase, HA, Lam, SS [0000-0002-5318-1760], and Apollo - University of Cambridge Repository

Subjects
Activated carbon, Waste cooking oil, Palm oil, Pyrolysis, Microwave pyrolysis
Abstract

Microwave pyrolysis using a well-mixed bed of activated carbon as both the microwave absorber and reaction bed was investigated for its potential to recover useful products from waste palm cooking oil – a cooking oil widely used in Asia. The carbon bed provided rapid heating (∼18 °C/min) and a localized reaction hot zone that thermally promoted extensive pyrolysis cracking of the waste oil at 450 °C, leading to increased production of a biofuel product in a process taking less than 25 min. It also created a reducing reaction environment that prevented the formation of undesirable oxidized compounds in the biofuel. The pyrolysis produced a biofuel product that is low in oxygen, free of sulphur, carboxylic acid and triglycerides, and which also contains light C$_{10}$-C$_{15}$ hydrocarbons and a high calorific value nearly comparable to diesel fuel, thus showing great potential to be used as fuel. This pyrolysis approach offers an attractive alternative to transesterification that avoids the use of solvents and catalysts, and the need to remove free fatty acids and glycerol from the hydrocarbon product. The pyrolysis apparatus operated with an electrical power input of 1.12 kW was capable of producing a biofuel with an energy content equivalent to about 3 kW, showing a positive energy ratio of 2.7 and ≥73% recovery of the energy input to the system. The results show that the pyrolysis approach has huge potential as a technically and energetically viable means for the recovery of biofuels from the waste oil.

Published
2016
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20. Progress in waste oil to sustainable energy, with emphasis on pyrolysis techniques

Author

Lam, SS, Liew, RK, Jusoh, A, Chong, CT, Ani, FN, Chase, HA, Lam, SS [0000-0002-5318-1760], and Apollo - University of Cambridge Repository

Subjects
Used oil, Sustainable energy, Waste oil, Pyrolysis, Microwave pyrolysis, Waste to energy
Abstract

This paper begins with a review on the current techniques used for the treatment and recovery of waste oil, which is then followed by an extensive review of the recent achievements in the sustainable development and utilization of pyrolysis techniques in energy recovery from waste oils. The advantages and limitations shown by the use of pyrolysis technique and other current techniques were discussed along with the future research that can be performed on the pyrolysis of waste oil. It was revealed that the current techniques (transesterification, hydrotreating, gasification, solvent extraction, and membrane technology) are yet to be sustainable or completely feasible for waste oil treatment and recovery. It was established that pyrolysis techniques offer a number of advantages over other existing techniques in recovering both the energetic and chemical value of waste oil by generating potentially useful pyrolysis products suitable for future reuse. In particular, microwave pyrolysis shows a distinct advantage in providing a rapid and energy-efficient heating compared to conventional pyrolysis techniques, and thus facilitating increased production rates. It was found that microwave pyrolysis of waste oil showed good performance with respect to product yield, reaction time, energy consumption, and product quality, and thus showing exceptional promise as a sustainable means for energy recovery from waste oils. Nevertheless, it was revealed that some important characteristics of the pyrolysis process have yet to be fully investigated. It was thus concluded that more studies are needed to extend existing understanding in the optimal reaction and process parameters in order to develop the pyrolysis technology to be a sustainable and commercially viable route for energy recovery from problematic waste oils.

Published
2016

21. Microwave-assisted pyrolysis with chemical activation, an innovative method to convert orange peel into activated carbon with improved properties as dye adsorbent

Author

Lam, SS, Liew, RK, Wong, YM, Yek, PNY, Ma, NL, Lee, CL, Chase, HA, and Apollo - University of Cambridge Repository

Subjects
Optimization, Response surface methodology, Activated carbon, Adsorbent, Microwave, Pyrolysis
Abstract

Microwave-assisted pyrolysis with chemical activation was developed and optimized to transform orange peel into activated carbon (AC) desirable for use as a dye adsorbent. The orange peel was first carbonized via microwave-assisted pyrolysis to produce a biochar, which was then activated and converted into AC via chemical impregnation coupled with microwave-assisted pyrolysis. The process parameters involved was optimized to maximize the yield of AC and its adsorption efficiency on malachite green dye using response surface methodology adopting central composite design. The use of microwave-assisted pyrolysis provided a fast heating rate and short process time in converting orange peel into AC, recording a heating rate of up to 112 °C/min in a process taking about 25 min, representing a method that is potentially faster and more energy efficient compared to that shown by the method commonly performed using conventional heating source (≥1 h). The results showed that AC with the highest yield (87 wt% of biochar) and optimal adsorption efficiency (28.5 mg of dye/g of AC) can be obtained by performing chemical impregnation at an impregnation ratio of 1:1 coupled with microwave-assisted pyrolysis under microwave irradiation (heating) for 5 min using 550 W of microwave power. The addition of chemical activation with alkali metal hydroxides resulted in the production of AC with improved properties. The AC showed a highly porous structure containing high content of fixed carbon (83 wt%) and high BET surface area (1350 m 2 /g). The adsorption–desorption isotherm showed a combination of Type I and Type II isotherms, which indicates the presence of microporous-mesoporous structure, thus exhibiting a characteristic of improved pores accessibility and high adsorption capacity. Combined with the detection of low ash (3.2 wt%) and moisture content (5 wt%), the AC shows great promise as a high-grade dye adsorbent with high adsorption capacity and potentially increased durability since a low moisture content could increase the rate of adsorption of dye contaminants and a high ash content could promote undesirable catalytic reactions and reduce the adsorption capacity and reactivation efficiency of AC. The recovery of AC with improved properties and the desirable process features (fast heating rate, short process time) suggest the great potential of this method as an alternative for the treatment and recovery of fruit peel.

Published
2017
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22. Pyrolysis using microwave absorbents as reaction bed: An improved approach to transform used frying oil into biofuel product with desirable properties

Author

Lam, SS, Wan Mahari, WA, Jusoh, A, Chong, CT, Lee, CL, Chase, HA, and Apollo - University of Cambridge Repository

Subjects
microwave, biofuel, absorbent, cooking oil, pyrolysis, oil
Abstract

Used frying oil (UFO), a waste produced in large volume each year worldwide, represents a potential resource for biofuel production rather than a disposal problem for modern society. Pyrolysis technique using microwave heating offers a promising approach for the conversion of UFO into biofuel products with improved properties. In this study, pyrolysis of UFO was performed by contacting with a bed of microwave absorbents heated by microwave radiation. The pyrolysis approach was examined using different materials as the reaction bed, comprising particulate carbon, activated carbon and mesoporous aluminosilicate (MCM-41). The use of particulate and activated carbon as the reaction bed provided a fast heating rate and extensive cracking capacity to pyrolyze the used oil, thus showing favorable features that could lead to short process time and less energy usage. This resulted in a production of a high yield of a biofuel product (up to 73 wt%) in a process taking less than 35 min. The biofuel showed a composition dominated by light C$_{5}$-C$_{20}$ aliphatic hydrocarbons with low amounts of oxygenated compounds (≤11%). In particular, the oil product obtained from activated carbon bed showed a low nitrogen content and was free of carboxylic acid and sulphur. The absence of carboxylic acids with low amounts of oxygenated compounds could reduce the formation of oxygenated by-products that could generate undesirable acidic tar or potentially hazardous sludge in the biofuel during storage. Combined with the detection of a high calorific value (46 MJ/kg) nearly comparable to diesel fuel, the biofuel shows great promise to be upgraded for use as a ‘cleaner’ fuel source with potentially reduced oxygenated by-products plus low or zero emissions of NO$_{x}$ and SO$_{x}$ during the use of the fuel in combustion process. This study also revealed that the use of activated carbon bed results in the highest energy recovery (88–90%) from the used frying oil. Our results demonstrated that the use of a microwave-heated reaction bed of activated carbon shows great potential as an improved and sustainable pyrolysis approach that is energy-efficient and timesaving for the recycling of used frying oil into a biofuel product with desirable properties. This pyrolysis approach provides an alternative to transesterification that avoids the use of solvents and catalysts, and thus could be developed further as a promising route to recycle various types of waste and biomass materials.

Published
2017

23. Catalytic microwave pyrolysis of waste engine oil using metallic pyrolysis char

Author

Lam, SS, Liew, RK, Cheng, CK, Chase, HA, Lam, SS [0000-0002-5318-1760], and Apollo - University of Cambridge Repository

Subjects
Waste, Catalyst, Char, Oil, Pyrolysis
Abstract

Microwave pyrolysis was performed on waste engine oil pre-mixed with different amounts of metallic-char catalyst produced previously from a similar microwave pyrolysis process. The metallic-char catalyst was first prepared by pretreatment with calcination followed by analyses to determine its various properties. The heating characteristics of the mixture of waste oil and metallic-char during the pyrolysis were investigated, and the catalytic influence of the metallic-char on the yield and characteristics of the pyrolysis products are discussed with emphasis on the composition of oil and gaseous products. The metallic-char, detected to have a porous structure and high surface area (124 m2/g), showed high thermal stability in a N2 atmosphere and it was also found to have phases of metals and metal oxides attached or adsorbed onto the char, representing a potentially suitable catalyst to be used in pyrolysis cracking process. The metallic-char initially acted as an adsorptive-support to adsorb metals, metal oxides and waste oil. Then, the char became a microwave absorbent that absorbed microwave energy and heated up to a high temperature in a short time and it was found to generate arcing and sparks during microwave pyrolysis of the waste oil, resulting in the formation of hot spots (high temperature sites with temperature up to 650 °C) within the reactor under the influence of microwave heating. The presence of this high temperature metallic-char, the amounts of which are likely to increase when increasing amounts of metallic-char were added to the waste oil (5, 10, and 20 wt% of the amount of waste oil added to the reactor), had provided a reducing chemical environment in which the metallic-char acted as an intermediate reductant to reduce the adsorbed metals or metal oxides into metallic states, which then functioned as a catalyst to provide more reaction sites that enhanced the cracking and heterogeneous reactions that occurred during the pyrolysis to convert the waste oil to produce higher yields of light hydrocarbons, H2 and CO gases in the pyrolysis products, recording a yield of up to 74 wt% of light C5–C10 hydrocarbons and 42 vol% of H2 and CO gases. The catalytic microwave pyrolysis produced 65–85 wt% yield of pyrolysis-oil containing C5–C20 hydrocarbons that can potentially be upgraded to produce transport-grade fuels. In addition, the recovered pyrolysis-gases (up to 33 wt%) were dominated by aliphatic hydrocarbons (up to 78 vol% of C1–C6 hydrocarbons) and significant amounts of valuable syngas (up to 42 vol% of H2 and CO in total) with low heating values (LHV) ranging from 4.7 to 5.5 MJ/m3, indicating that the pyrolysis-gases could also be used as a gaseous fuel or upgraded to produce more hydrogen as a second-generation fuel. The results indicate that the metallic-char shows advantages for use as a catalyst in microwave pyrolysis treatment of problematic waste oils. [Graphical abstract - see article]

Published
2015

24. Lupus Nephritis and Pregnancy

Author

PACKHAM, DK, LAM, SS, NICHOLLS, K, FAIRLEY, KF, and KINCAID-SMITH, PS

Abstract

Sixty-four pregnancies in 41 women with biopsy proven lupus nephritis between 1965 and 1991 were analysed to record fetal and maternal outcome and identify risk factors for poor outcome. Of 65 fetuses, 22 (34 per cent) were lost (including therapeutic abortions), 19 (30 per cent) were live born but premature (≤36 weeks gestation) and 24 (37 per cent) were term. Fetal loss after 20 weeks gestation was 19 per cent. Twelve per cent of 25 fetuses whose birthweight was recorded were small for gestational age. Maternal renal function deteriorated in 19 per cent of pregnancies but was irreversible post-partum in only one woman (2 per cent). Hypertension was recorded in 44 per cent of pregnancies, developed early (≤32 weeks gestation) in 28 per cent and was severe in 13 per cent. Treated hypertension predated 17 per cent of pregnancies and in 6 per cent (included in the overall incidence of hypertension) exacerbation occurred during pregnancy despite continued anti-hypertensive medication. Nine women (22 per cent) who developed de novo hypertension in pregnancy had permanent hypertension post-partum. Increased proteinuria was recorded in 48 per cent of pregnancies and was irreversible post partum in 5 per cent. Comparison of pregnancies occurring before or after diagnosis was made by renal biopsy failed to show any significant difference in fetal outcome. Pregnancies occurring after the diagnosis of glomerulonephritis were associated with a significantly lower incidence of maternal hypertension, early hypertension, severe hypertension and increased proteinuria. The presence of the circulating lupus anticoagulant was clearly associated with a significantly high fetal loss rate although the incidence of maternal complications did not differ significantly between mothers positive or negative for lupus anticoagulant.

Published
1992

26. Characterizing persistent organic pollutants in seawater at a multifunctional international harbor influenced by industrial riverbank activities.

Author

Wardiani FE, Dong CD, Chen CW, Liu TK, Hsu ZP, Lam SS, and Wang LC

Abstract

The objective of this study is to comprehensively characterize persistent organic pollutants (POPs) in seawater at Kaohsiung Harbor, focusing on their concentrations, partitioning behaviors, and profiles in both particle and liquid phases. We analyzed 100 L seawater for each sample, finding total dioxin-like toxicity (PCDD/Fs + PCBs + PBDD/Fs) ranging from 0.00936 to 0.167 pg WHO-TEQ/L, with PCDD/Fs accounting for 68 % of total toxicity. POPs predominantly appeared in the particle phase, observed in over 80 % of samples, except for PCBs. The observed correlations between particulate matter (PM) and chlorinated POPs at sites receiving river effluents suggest shared pollution sources. The liquid partition of PCDD/Fs, PCBs, and PBDEs in the seawater shows an inverse relationship with log Kow and a direct proportionality with solubility, particularly above 0.1 μg/L. Furthermore, PBDEs in seawater can transform into PBDD/Fs upon UV light exposure, highlighting another potential pathway for the persistence and spread of these harmful contaminants in the environment. These findings emphasize the need for field-based investigations to assess PBDF formation in aquatic environments and underscore the importance of stronger mitigation strategies, including better wastewater treatment and stricter discharge regulations to reduce POPs in marine ecosystems., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Published
2024
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27. Toxic metal pollution and associated health risk in nonferrous metal smelting soil containing clay minerals.

Author

Cai K, Du J, Yan L, Luan Z, He Y, Shen J, Song Z, Zhao Z, Luan W, Liu X, and Lam SS

Subjects
China, Minerals chemistry, Minerals analysis, Metals, Heavy analysis, Metals, Heavy toxicity, Metallurgy, Aluminum Silicates chemistry, Metals analysis, Clay chemistry, Soil Pollutants analysis, Soil Pollutants toxicity, Soil chemistry
Abstract

Given the research situation of toxic metals (TMs) pollution in farmland soil, it is very critical to study the clay influence on TMs environmental behavior to meet the aim of lowering TMs pollution. This research explores the association among clay minerals and TMs and the health risks in TMs combined polluted farmland of northern China. In this study, agricultural soil, wheat grain, and atmospheric sediments from nonferrous metal smelting (NMS) areas were collected and investigated to determine the effect of clay minerals on TMs. The results show that the content ranges of Cd (0.199 mg/kg ∼1.98 × 10 2  mg/kg), Pb (0.228 × 10 2  mg/kg ∼ 4.87 × 10 3  mg/kg), Cu (0.187 × 10 2  mg/kg ∼ 4.57 × 10 3  mg/kg), and Zn (0.559 × 10 2  mg/kg ∼ 3.04 × 10 3  mg/kg) in the agricultural soil. In particular, Cd has reached heavy pollution by the high pollution index (6.74). The findings indicate that Cd and Pb in wheat grain were influenced by their exchangeable fractions in soil, according to a significant relationship between Cd and Pb in soil and wheat grain. XRD-SEM suggests that TMs come from atmospheric sediments associated with NMS emissions by microsphere signatures with surface burn marks. Meanwhile, Geographical detector indicated that clay was the primary contributor to spatial distribution of Cd and Pb. In addition, XRD results showed that I/S (a mixed layer of illite and smectite), illite, chlorite, and kaolinite co-existed. Whereas the clay minerals with this ratio did not demonstrate better adsorption capacities for Cd and Pb due to the Cd percentage of the residual fraction being less than 9%. The result of negative correlation between exchangeable Cd and clay minerals implies that illite, chlorite, and kaolinite may preferentially adsorb Cd and Pb. It is similar to the relationship between Cd and Pb in wheat grain and illite, chlorite, and kaolinite. In addition, the health assessment result show that the negative correlation between clay minerals and the noncarcinogenic hazard quotient (HQ) and indicate that clay minerals could reduce the noncarcinogenic risk of Pb and Cd for children. Our findings provide a potential mechanism and application of clay minerals for the remediation of soil contaminated with TMs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Published
2024
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28. A new filtration system for extraction and accurate quantification of microplastics.

Author

Kim J, Kwon J, Kwon J, Siddiqui MZ, Woo G, Choi M, Hong S, Ma C, Kumagai S, Watanabe A, Teramae N, Lam SS, and Kim YM

Abstract

The analysis of microplastics is crucial due to their widespread occurrence and significant impact as environmental pollutants. Appropriate extraction and analytical techniques are necessary to evaluate the abundance, dispersal, and effects of microplastics. In this context, the filtration step to extract microplastics from solution media is indispensable for quantifying microplastics accurately. Usually, a pretreatment procedure such as density separation or solvent extraction is employed before filtration. Nevertheless, the adsorption of microplastic particles onto the glassware surface is known to occur and careful rinsing is inevitable for a suitable recovery rate. The study presents a novel filtration device developed for easy use to increase microplastic recovery from liquid samples. Fluorescent polyethylene (PE) particles were used to examine recovery by optical microscopy and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). The conventional filtration system (CFS) exhibited lower microplastic recovery (45.1 ± 7.9%, n = 10) due to the adsorption of microplastics onto the inner surface and the bottom edge of the upper glass funnel. In contrast, the newly developed modified filtration system (MFS) enables fast suction of liquid samples by removing the glass frit with the upper glass funnel and filter being spatially separated. The significantly improved recovery rates using MFS for PE particles were 100% ( n = 5) and 93.4 ± 3.4% ( n = 10), respectively, confirming the feasibility of the newly developed filtration system to analyze microplastics using Py-GC/MS. The study highlights the importance of filtration processing in establishing analytical standards for assessing and managing microplastics by suggesting MFS as an advanced filtration system.

Published
2024
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29. Efficacy of Fe-Mg-bimetallic biochar in stabilization of multiple heavy metals-contaminated soil and attenuation of toxicity in spinach (Spinacia oleracea L.).

Author

Irshad MK, Lee JC, Aqeel M, Javed W, Noman A, Lam SS, Naggar AE, Niazi NK, Lee HH, Ibrahim M, and Lee SS

Subjects
Magnesium chemistry, Soil chemistry, Photosynthesis drug effects, Plant Roots drug effects, Plant Roots metabolism, Superoxide Dismutase metabolism, Catalase metabolism, Oxidative Stress drug effects, Lead toxicity, Lead metabolism, Cadmium toxicity, Ascorbate Peroxidases metabolism, Spinacia oleracea drug effects, Spinacia oleracea metabolism, Soil Pollutants toxicity, Metals, Heavy toxicity, Iron chemistry, Charcoal chemistry
Abstract

Globally, soil contamination with heavy metals (HMs) pose serious threats to soil health, crop productivity, and human health. The present investigation involved synthesis and analysis of biochar with bimetallic combination of iron and magnesium (Fe-Mg-BC). Our study evaluated how Fe-Mg-BC affects the absorption of cadmium (Cd), lead (Pb), and copper (Cu) in spinach (Spinacia oleracea L.) and remediation of soil contaminated with multiple HMs. Results demonstrated the successful loading of iron (Fe) and magnesium (Mg) onto pristine biochar (BC) derived from peanut shells. The addition of Fe-Mg-BC (3%) notably increased spinach biomass, enhancing photosynthesis, transpiration, stomatal conductance, and intercellular CO 2 levels by 22%, 21%, 103%, and 15.3%, respectively. Compared to control, Fe-Mg-BC (3%) suppressed metal-induced oxidative stress by boosting levels of superoxide dismutase (SOD), ascorbate peroxidase (APX) and catalase (CAT) in roots by 40.9%, 57%, 54.8 %, and in shoots by 55.5%, 65.5%, and 37.4% in shoots, respectively. The Fe-Mg-BC effectively reduced the uptake of Cd, Pb, and Cu in spinach tissues by transforming their bioavailable fractions to non-bioavailable forms. The Fe-Mg-BC (3%) significantly reduced the mobility of Cd, Pb and Cu in soil and limited the concentration of Cd, Pb, and Cu in plant roots by 34.1%, 79.2%, 47%, and shoots by 56.3%, 43.3%, and 54.1%, respectively, compared to control. These findings underscore the potential of Fe-Mg-BC as a promising amendment for reclaiming soils contaminated with variety of HMs, thereby making a significant contribution to the promotion of safer food production., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Published
2024
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30. Synergetic anaerobic digestion of food waste for enhanced production of biogas and value-added products: strategies, challenges, and techno-economic analysis.

Author

Sharma P, Parakh SK, Tsui TH, Bano A, Singh SP, Singh VP, Lam SS, Nadda AK, and Tong YW

Subjects
Anaerobiosis, Bioreactors, Food, Methane metabolism, Refuse Disposal methods, Biofuels, Food Loss and Waste
Abstract

The generation of food waste (FW) is increasing at an alarming rate, contributing to a total of 32% of all the waste produced globally. Anaerobic digestion (AD) is an effective method for dealing with organic wastes of various compositions, like FW. Waste valorization into value-added products has increased due to the conversion of FW into biogas using AD technology. A variety of pathways are adopted by microbes to avoid unfavorable conditions in AD, including competition between sulfate-reducing bacteria and methane (CH 4 )-forming bacteria. Anaerobic bacteria decompose organic matter to produce biogas, a digester gas. The composition depends on the type of raw material and the method by which the digestion process is conducted. Studies have shown that the biogas produced by AD contains 65-75% CH 4 and 35-45% carbon dioxide (CO 2 ). Methanothrix soehngenii and Methanosaeta concilii are examples of species that convert acetate to CH 4 and CO 2 . Methanobacterium bryantii , Methanobacterium thermoautotrophicum , and Methanobrevibacter arboriphilus are examples of species that produce CH 4 from hydrogen and CO 2 . Methanobacterium formicicum , Methanobrevibacter smithii , and Methanococcus voltae are examples of species that consume formate, hydrogen, and CO 2 and produce CH 4 . The popularity of AD has increased for the development of biorefinery because it is seen as a more environmentally acceptable alternative in comparison to physico-chemical techniques for resource and energy recovery. The review examines the possibility of using accessible FW to produce important value-added products such as organic acids (acetate/butyrate), biopolymers, and other essential value-added products.

Published
2024
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31. A review of phytoremediation of environmental lead (pb) contamination.

Author

Zhang L, Zhu Y, Gu H, Lam SS, Chen X, Sonne C, and Peng W

Subjects
Plants metabolism, Soil chemistry, Charcoal chemistry, Environmental Pollution, Metals, Heavy metabolism, Metals, Heavy analysis, Biodegradation, Environmental, Lead metabolism, Lead analysis, Soil Pollutants metabolism, Soil Pollutants analysis
Abstract

An estimated one billion people globally are exposed to hazardous levels of lead (Pb), resulting in intellectual disabilities for over 600,000 children each year. This critical issue aligns with the expanding worldwide population and the demand for food security, emphasizing the urgency of effectively addressing heavy metal pollution especially from Pb for sustainable development. Phytoremediation, a highly favoured approach in conjunction with conventional physical, chemical, and microbial methods, is a promising approach to mitigating soil and environmental contamination. In this review, we delve into a range of soil pollution mitigation strategies, with focus on the mechanisms that underpin the phytoremediation of environmental Pb. This detailed exploration sheds light on the efficacy and complexities of utilizing plants for the detoxification and removal of lead from contaminated environments. It also examines strategies to enhance phytoremediation by incorporating microbiology, composting, nanotechnology, and foliar spraying. The potential remediation strategies largely depend on the investigation and incorporation of environmentally friendly catalysts, as well as the utilization of innovative methods such as genetic engineering to improve phytoremediation processes. Studies have also shown that biochar has the capability to lower heavy metal concentrations in plant branches by over 50%, without affecting the pH of the soil. Specifically, magnetic biochar (MBC) has been shown to decrease lead levels in plants by up to 42%. Employing these methods showcases an effective strategy to enhance the efficacy of remediation techniques and fosters sustainable solutions to the pervasive issue of Pb pollution, thereby contributing to sustainable development efforts globally., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Published
2024
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32. Revitalizing plastic wastes employing bio-circular-green economy principles for carbon neutrality.

Author

Rani A, Negi S, Fan C, Lam SS, Kim H, and Pan SY

Subjects
Refuse Disposal methods, Refuse Disposal economics, Carbon Footprint, Carbon chemistry, Plastics, Recycling, Waste Management methods, Waste Management economics
Abstract

The use of plastics has become deeply ingrained in our society, and there are no indications that its prevalence will decrease in the foreseeable future. This article provides a comprehensive overview of the global plastic waste disposal landscape, examining it through regional perspectives, various management technologies (dumping or landfilling, incineration, and reuse and recycling), and across different sectors including agriculture and food, textile, tourism, and healthcare. Notably, this study compiles the findings on life-cycle carbon footprints associated with various plastic waste management practices as documented in the literature. Employing the bio-circular-green economy model, we advocate for the adoption of streamlined and sustainable approaches to plastic management. Unique management measures are also discussed including the utilization of bioplastics combined with smart and efficient collection processes that facilitate recycling, industrial composting, or anaerobic digestion. Moreover, the integration of advanced recycling methods for conventional plastics with renewable energy, the establishment of plastic tax and credits, and the establishment of extended producer responsibility are reviewed. The success of these initiatives relies on collaboration and support from peers, industries, and consumers, ultimately contributing to informed decision-making and fostering sustainable practices in plastic waste management., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Published
2024
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33. Inhibitory modulation of action potentials in crayfish motor axons by fluoxetine.

Author

Wang S, Lam SS, Aguilar A, Anakwe S, Barahona K, Haider H, Hunyadi O, Jain K, Kolodziejski D, Lal A, Li M, MacKenzie F, Miller J, Nardin O, Nguyen E, Pappu J, Rodriguez M, and Lin JW

Subjects
Animals, Astacoidea drug effects, Astacoidea physiology, Fluoxetine pharmacology, Action Potentials drug effects, Action Potentials physiology, Motor Neurons drug effects, Motor Neurons physiology, Axons drug effects, Axons physiology
Abstract

The goal of this report is to explore how K2P channels modulate axonal excitability by using the crayfish ventral superficial flexor preparation. This preparation allows for simultaneous recording of motor nerve extracellular action potentials (eAP) and intracellular excitatory junctional potential (EJP) from a muscle fiber. Previous pharmacological studies have demonstrated the presence of K2P-like channels in crayfish. Fluoxetine (50 µM) was used to block K2P channels in this study. The blocker caused a gradual decline, and eventually complete block, of motor axon action potentials. At an intermediate stage of the block, when the peak-to-peak amplitude of eAP decreased to ∼60%-80% of the control value, the amplitude of the initial positive component of eAP declined at a faster rate than that of the negative peak representing sodium influx. Furthermore, the second positive peak following this sodium influx, which corresponds to the after-hyperpolarizing phase of intracellularly recorded action potentials (iAP), became larger during the intermediate stage of eAP block. Finally, EJP recorded simultaneously with eAP showed no change in amplitude, but did show a significant increase in synaptic delay. These changes in eAP shape and EJP delay are interpreted as the consequence of depolarized resting membrane potential after K2P channel block. In addition to providing insights to possible functions of K2P channels in unmyelinated axons, results presented here also serve as an example of how changes in eAP shape contain information that can be used to infer alterations in intracellular events. This type of eAP-iAP cross-inference is valuable for gaining mechanistic insights here and may also be applicable to other model systems., (© 2024 Wiley Periodicals LLC.)

Published
2024
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34. Boosting acetaminophen degradation in water by peracetic acid activation: A novel approach using chestnut shell-derived biochar at varied pyrolysis temperatures.

Author

Nguyen TK, Nguyen TB, Chen CW, Chen WH, Bui XT, Lam SS, and Dong CD

Subjects
Adsorption, Water Purification methods, Charcoal chemistry, Acetaminophen chemistry, Water Pollutants, Chemical chemistry, Pyrolysis, Peracetic Acid chemistry
Abstract

In this study, biochar derived from chestnut shells was synthesized through pyrolysis at varying temperatures from 300 °C to 900 °C. The study unveiled that the pyrolysis temperature is pivotal in defining the physical and chemical attributes of biochar, notably its adsorption capabilities and its role in activating peracetic acid (PAA) for the efficient removal of acetaminophen (APAP) from aquatic environments. Notably, the biochar processed at 900 °C, referred to as CN900, demonstrated an exceptional adsorption efficiency of 55.8 mg g -1 , significantly outperforming its counterparts produced at lower temperatures (CN300, CN500, and CN700). This enhanced performance of CN900 is attributed to its increased surface area, improved micro-porosity, and a greater abundance of oxygen-containing functional groups, which are a consequence of the elevated pyrolysis temperature. These oxygen-rich functional groups, such as carbonyls, play a crucial role in facilitating the decomposition of the O-O bond in PAA, leading to the generation of reactive oxygen species (ROS) through electron transfer mechanisms. This investigation contributes to the development of sustainable and cost-effective materials for water purification, underscoring the potential of chestnut shell-derived biochar as an efficient adsorbent and catalyst for PAA activation, thereby offering a viable solution for environmental cleanup efforts., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Published
2024
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35. Instant catapult steam explosion combined with ammonia water: A complex technology for detoxification of aflatoxin-contaminated peanut cake with the aim of producing a toxicity-free and nutrients retention of animal feed.

Author

Xie H, Gao L, Li Z, Mao G, Zhang H, Wang F, Lam SS, and Song A

Abstract

Aflatoxin is one of the most toxic biotoxins found in contaminated agricultural products. It has strong mutagenicity, carcinogenesis and teratogenicity to humans and animals. In this study, instant catapult steam explosion combined with ammonia water was examined for its potential to degrade aflatoxin B 1 in peanut cake in order to improve its utilization as a toxic-free animal feed. Incubation of AFB 1 -containing peanut cake followed by processing with Instant Catapult Steam Explosion (ICSE) led to approximately 79.03 % degradation of AFB 1 , while the degradation of AFB 1 was up to 91.48 % under the treatment of ICSE combined with 4 % NH₃·H₂O at 1.2 MPa in 200 s of process time. After treatment, nutrients in peanut cake were not significantly changed. The toxicity of AFB 1 degradation products was evaluated and the results showed that the toxicity of these products were found to be substantially less than that possessed by AFB 1 . A low chemical pollution, efficient and toxic-free technology system of AFB 1 degradation was established, which detoxify aflatoxin-contaminated biomass for sustainable and safe utilization of agricultural biomass as animal feed., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Published
2024
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36. Insights into the influence of polystyrene microplastics on the bio-degradation behavior of tetrabromobisphenol A in soil.

Author

Chang J, Liang J, Zhang Y, Zhang R, Fang W, Zhang H, Lam SS, Zhang P, and Zhang G

Subjects
Oxidoreductases metabolism, Soil chemistry, Adsorption, Polystyrenes chemistry, Polybrominated Biphenyls toxicity, Microplastics toxicity, Soil Pollutants toxicity, Soil Pollutants chemistry, Soil Microbiology, Biodegradation, Environmental
Abstract

Soil contamination by emerging pollutants tetrabromobisphenol A (TBBPA) and microplastics has become a global environmental issue in recent years. However, little is known about the effect of microplastics on degradation of TBBPA in soil, especially aged microplastics. In this study, the effect of aged polystyrene (PS) microplastics on the degradation of TBBPA in soil and the mechanisms were investigated. The results suggested that the aged microplastics exhibited a stronger inhibitory effect on the degradation of TBBPA in soil than the pristine microplastics, and the degradation efficiency of TBBPA decreased by 21.57% at the aged microplastic content of 1%. This might be related to the higher TBBPA adsorption capacity of aged microplastics compared to pristine microplastics. Aged microplastics strongly altered TBBPA-contaminated soil properties, reduced oxidoreductase activity and affected microbial community composition. The decrease in soil oxidoreductase activity and relative abundance of functional microorganisms (e.g., Bacillus, Pseudarthrobacter and Sphingomonas) caused by aged microplastics interfered with metabolic pathways of TBBPA. This study indicated the importance the risk assessment and soil remediation for TBBPA-contaminated soil with aged microplastics., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Published
2024
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38. Upcycling crab shell waste into biochar for treatment of palm oil mill effluent via microwave pyrolysis and activation.

Author

Yang Y, Foong SY, He Y, Liew RK, Ma NL, Yek PNY, Ge S, Naushad M, and Lam SS

Subjects
Animals, Palm Oil, Microwaves, Pyrolysis, Steam, Industrial Waste analysis, Brachyura, Charcoal
Abstract

The escalating consumer demand for crabs results in a growing amount of waste, including shells, claws, and other non-edible parts. The resulting crab shell waste (CSW) is disposed of via incineration or landfills which causes environmental pollution. CSW represents a potential biological resource that can be transformed into valuable resources via pyrolysis technique. In this study, microwave pyrolysis of CSW using self-purging, vacuum, and steam activation techniques was examined to determine the biochar production yield and its performance in treating palm oil mill effluent (POME). The biochar produced through microwave pyrolysis exhibits yields ranging from 50 to 61 wt%, showing a hard texture, low volatile matter content (≤34.1 wt%), and high fixed carbon content (≥58.3 wt%). The KOH-activated biochar demonstrated a surface area of up to 177 m 2 /g that is predominantly composed of mesopores, providing a good amount of adsorption sites for use as adsorbent. The biochar activated with steam removed 8.3 mg/g of BOD and 42 mg/g of COD from POME. The results demonstrate that microwave pyrolysis of CSW is a promising technology to produce high-quality biochar as an adsorbent for POME treatment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Published
2024
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39. Renal relapse in children and adolescents with childhood-onset lupus nephritis: a 20-year study.

Author

Chan EY, Yap DY, Wong WH, Wong SW, Lin KY, Hui FY, Li JY, Lam SS, Wong JK, Lai FF, Ho TW, Tong PC, Lai WM, Chan TM, and Ma AL

Subjects
Child, Humans, Adolescent, Immunosuppressive Agents therapeutic use, Azathioprine therapeutic use, Retrospective Studies, Mycophenolic Acid, Treatment Outcome, Prednisolone therapeutic use, Recurrence, Cyclophosphamide, Remission Induction, Lupus Nephritis drug therapy, Lupus Nephritis epidemiology, Lupus Nephritis diagnosis
Abstract

Objectives: There is little data on renal relapse in childhood-onset LN (cLN). We investigate the incidence, predictive factors and outcomes related to renal relapse., Methods: We conducted a retrospective cohort study of all cLN diagnosed at ≤18 years between 2001-2021 to investigate the incidence and outcomes related to renal relapse., Results: Ninety-five Chinese cLN patients (91% proliferative LN) were included. Induction immunosuppression was prednisolone and CYC [n = 36 (38%)] or MMF [n = 33 (35%)]. Maintenance immunosuppression was prednisolone and MMF [n = 53 (54%)] or AZA [n = 29 (31%)]. The rates of complete remission/partial remission (CR/PR) at 12 months were 78.9%/7.4%. Seventy renal relapses occurred in 39 patients over a follow-up of 10.2 years (s.d. 5.9) (0.07 episode/patient-year). Relapse-free survival was 94.7, 86.0, 80.1, 71.2, 68.3, 50.3 and 44.5% at 1, 2, 3, 4, 5, 10 and 20 years, respectively. Multivariate analysis showed that LN diagnosis <13.1 years [adjusted hazard ratio (HRadj) 2.59 995% CI 1.27, 5.29), P = 0.01], AZA maintenance [HRadj 2.20 (95% CI 1.01, 4.79), P = 0.05], PR [HRadj 3.9 (95% CI 1.03, 9.19), P = 0.01] and non-remission [HRadj 3.08 (95% CI 1.35, 11.3), P = 0.04] at 12 months were predictive of renal relapse. Renal relapse was significantly associated with advanced chronic kidney disease (stages 3-5) and end-stage kidney disease (17.9% vs 1.8%, P < 0.01). Furthermore, patients with renal relapse showed an increased incidence of infections (30.8% vs 10.7%, P = 0.02), osteopenia (38.5% vs 17.9%, P = 0.04) and hypertension (30.8% vs 7.1%, P < 0.01)., Conclusion: Renal relapse is common among cLN, especially among young patients, and is associated with an increased incidence of morbidity and mortality. Attaining CR and the use of MMF appear to decrease the incidence of renal relapse., (© The Author(s) 2023. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Published
2024
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40. Soil Geobacteraceae are the key predictors of neurotoxic methylmercury bioaccumulation in rice.

Author

Zhong H, Tang W, Li Z, Sonne C, Lam SS, Zhang X, Kwon SY, Rinklebe J, Nunes LM, Yu RQ, Gu B, Hintelmann H, Tsui MT, Zhao J, Zhou XQ, Wu M, Liu B, Hao Y, Chen L, Zhang B, Tan W, Zhang XX, Ren H, and Liu YR

Subjects
Bioaccumulation, Microbiota drug effects, Soil chemistry, Methylmercury Compounds metabolism, Methylmercury Compounds analysis, Oryza metabolism, Oryza chemistry, Oryza microbiology, Soil Microbiology, Soil Pollutants metabolism, Soil Pollutants analysis
Abstract

Contamination of rice by the potent neurotoxin methylmercury (MeHg) originates from microbe-mediated Hg methylation in soils. However, the high diversity of Hg methylating microorganisms in soils hinders the prediction of MeHg formation and challenges the mitigation of MeHg bioaccumulation via regulating soil microbiomes. Here we explored the roles of various cropland microbial communities in MeHg formation in the potentials leading to MeHg accumulation in rice and reveal that Geobacteraceae are the key predictors of MeHg bioaccumulation in paddy soil systems. We characterized Hg methylating microorganisms from 67 cropland ecosystems across 3,600 latitudinal kilometres. The simulations of a rice-paddy biogeochemical model show that MeHg accumulation in rice is 1.3-1.7-fold more sensitive to changes in the relative abundance of Geobacteraceae compared to Hg input, which is recognized as the primary parameter in controlling MeHg exposure. These findings open up a window to predict MeHg formation and accumulation in human food webs, enabling more efficient mitigation of risks to human health through regulations of key soil microbiomes., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)

Published
2024
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41. A comprehensive study of artificial neural network for sensitivity analysis and hazardous elements sorption predictions via bone char for wastewater treatment.

Author

Biswas PP, Chen WH, Lam SS, Park YK, Chang JS, and Hoang AT

Subjects
Water, Neural Networks, Computer, Metals, Heavy, Water Purification, Water Pollutants, Chemical, Soil Pollutants
Abstract

Using bone char for contaminated wastewater treatment and soil remediation is an intriguing approach to environmental management and an environmentally friendly way of recycling waste. The bone char remediation strategy for heavy metal-polluted wastewater was primarily affected by bone char characteristics, factors of solution, and heavy metal (HM) chemistry. Therefore, the optimal parameters of HM sorption by bone char depend on the research being performed. Regarding enhancing HM immobilization by bone char, a generic strategy for determining optimal parameters and predicting outcomes is crucial. The primary objective of this research was to employ artificial neural network (ANN) technology to determine the optimal parameters via sensitivity analysis and to predict objective function through simulation. Sensitivity analysis found that for multi-metals sorption (Cd, Ni, and Zn), the order of significance for pyrolysis parameters was reaction temperature > heating rate > residence time. The primary variables for single metal sorption were solution pH, HM concentration, and pyrolysis temperature. Regarding binary sorption, the incubation parameters were evaluated in the following order: HM concentrations > solution pH > bone char mass > incubation duration. This approach can be used for further experiment design and improve the immobilization of HM by bone char for water remediation., Competing Interests: Declaration of Competing Interest The authors declare that they have no conflicts of interest to this work. We declare that we do not have any commercial or associative interest that represents a conflict of interest in connection with the work submitted., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Published
2024
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42. A novel porous lignocellulosic standing hierarchical hydroxyapatite for enhanced aqueous copper(II) removal.

Author

Liang Y, Jin X, Xu X, Wu Y, Ghfar AA, Lam SS, Sonne C, Aminabhavi TM, and Xia C

Abstract

Potentially toxic metal-polluted water resources are a heavily discussed topic the pollution by potentially toxic metals can cause significant health risks. Nanomaterials are actively developed towards providing high specific surface area and creating active adsorption sites for the treatment and remediation of these polluted waters. In an effort to tackle the limitations of conventional type adsorbents, nano-hydroxyapatite (HAp) was developed in this study by in situ generation onto wood powder, resulting in the formation of uniform hybrid powder (HAp@wood composite) structure consisting of HAp nanoparticles that showed the removal efficiency up to 80 % after 10 min; the maximum adsorption capacity for Cu(II) ions (98.95 mg/g-HAp) was higher compared to agglomerated nano-HAp (72.85 mg/g-HAp). The adsorption capacity of Cu(II) remained stable (89.85-107.66 mg/g-HAp) during the four adsorption-desorption cycles in multi-component system, thereby demonstrating high selectivity for Cu(II). This approach of using nanoparticle is relatively simple yet effective in improving the adsorption of potentially toxic metals and the developed approach can be used to develop advanced nanocomposites in commercial wastewater treatment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Published
2024
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43. Facile heteroatoms modification biochar production from mahogany (Swietenia macrophylla King) pericarps for enhanced the suppression of polycyclic aromatic hydrocarbon pollutants.

Author

Dong CD, Huang CP, Chen CW, Lam SS, Sonne C, Kang CK, and Hung CM

Subjects
Humans, Carbon Dioxide, Charcoal chemistry, Polycyclic Aromatic Hydrocarbons analysis, Environmental Pollutants
Abstract

Polycyclic aromatic hydrocarbons (PAHs) are critical environmental concerns due to their intrinsic toxic aromatic nature and concomitant circumstances that potentially harm the ecological and human health. In this study, converting mahogany (Swietenia macrophylla King) pericarps to value-added biochar by pyrolysis for evaluating the potential formation/destruction of biochar-bound PAHs was studied for the first time. This study designed and optimized the thermal processing conditions at 300-900 °C in the CO 2 or N 2 atmosphere, and heteroatoms (N, O, B, NB, and NS) were modified for mahogany pericarps biochar (MPBC) production. The MPBC500 exhibited significantly higher pyrolysis products of PAHs (2780 ± 38 ng g -1 ) than that of MPBC900 (78 ± 6 ng g -1 ) under N 2 without introducing modified elements. Specifically, the inhibition capacity of MPBC500 for PAHs under CO 2 was improved most efficiently by the active nitrogen species of the pyridinic N and pyrrolic N groups. The pyrolysis conditions and heteroatom modification of MPBC altered its physicochemical properties, that is, aromaticity and hydrophobicity, affecting the PAH concentration and composition in the pyrolysis products. This study reveals sustainable approaches to reduce the environmental footprint of biochar by focusing on increases in PAHs pollution in sustainable biochar produced from a low-carbon bioeconomy perspective., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Published
2024
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44. Driving sustainable circular economy in electronics: A comprehensive review on environmental life cycle assessment of e-waste recycling.

Author

He Y, Kiehbadroudinezhad M, Hosseinzadeh-Bandbafha H, Gupta VK, Peng W, Lam SS, Tabatabaei M, and Aghbashlo M

Subjects
Humans, Animals, Ecosystem, Recycling methods, Electronics, Metals, Life Cycle Stages, Refuse Disposal, Electronic Waste analysis, Waste Management methods
Abstract

E-waste, encompassing discarded materials from outdated electronic equipment, often ends up intermixed with municipal solid waste, leading to improper disposal through burial and incineration. This improper handling releases hazardous substances into water, soil, and air, posing significant risks to ecosystems and human health, ultimately entering the food chain and water supply. Formal e-waste recycling, guided by circular economy models and zero-discharge principles, offers potential solutions to this critical challenge. However, implementing a circular economy for e-waste management due to chemical and energy consumption may cause environmental impacts. Consequently, advanced sustainability assessment tools, such as Life Cycle Assessment (LCA), have been applied to investigate e-waste management strategies. While LCA is a standardized methodology, researchers have employed various routes for environmental assessment of different e-waste management methods. However, to the authors' knowledge, there lacks a comprehensive study focusing on LCA studies to discern the opportunities and limitations of this method in formal e-waste management strategies. Hence, this review aims to survey the existing literature on the LCA of e-waste management under a circular economy, shedding light on the current state of research, identifying research gaps, and proposing future research directions. It first explains various methods of managing e-waste in the circular economy. This review then evaluates and scrutinizes the LCA approach in implementing the circular bioeconomy for e-waste management. Finally, it proposes frameworks and procedures to enhance the applicability of the LCA method to future e-waste management research. The literature on the LCA of e-waste management reveals a wide variation in implementing LCA in formal e-waste management, resulting in diverse results and findings in this field. This paper underscores that LCA can pinpoint the environmental hotspots for various pathways of formal e-waste recycling, particularly focusing on metals. It can help address these concerns and achieve greater sustainability in e-waste recycling, especially in pyrometallurgical and hydrometallurgical pathways. The recovery of high-value metals is more environmentally justified compared to other metals. However, biometallurgical pathways remain limited in terms of environmental studies. Despite the potential for recycling e-waste into plastic or glass, there is a dearth of robust background in LCA studies within this sector. This review concludes that LCA can offer valuable insights for decision-making and policy processes on e-waste management, promoting environmentally sound e-waste recycling practices. However, the accuracy of LCA results in e-waste recycling, owing to data requirements, subjectivity, impact category weighting, and other factors, remains debatable, emphasizing the need for more uncertainty analysis in this field., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Published
2024
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45. Recent progress on phytoremediation of urban air pollution.

Author

Duan X, Gu H, Lam SS, Sonne C, Lu W, Li H, Chen X, and Peng W

Subjects
Humans, Biodegradation, Environmental, Ecosystem, Particulate Matter analysis, Cities, Plants metabolism, Environmental Monitoring, Greenhouse Gases, Air Pollution analysis, Air Pollutants analysis
Abstract

The rapid growth of population and economy has led to an increase in urban air pollutants, greenhouse gases, energy shortages, environmental degradation, and species extinction, all of which affect ecosystems, biodiversity, and human health. Atmospheric pollution sources are divided into direct and indirect pollutants. Through analysis of the sources of pollutants, the self-functioning of different plants can be utilized to purify the air quality more effectively. Here, we explore the absorption of greenhouse gases and particulate matter in cities as well as the reduction of urban temperatures by plants based on international scientific literature on plant air pollution mitigation, according to the adsorption, dust retention, and transpiration functions of plants. At the same time, it can also reduce the occurrence of extreme weather. It is necessary to select suitable tree species for planting according to different plant functions and environmental needs. In the context of tight urban land use, the combination of vertical greening and urban architecture, through the rational use of plants, has comprehensively addressed urban air pollution. In the future, in urban construction, attention should be paid to the use of heavy plants and the protection and development of green spaces. Our review provides necessary references for future urban planning and research., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

Published
2024
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46. Ancient forest plants possess cytotoxic properties causing liver cancer HepG2 cell apoptosis.

Author

Yue X, Ling Ma N, Zhong J, Yang H, Chen H, Yang Y, Lam SS, Yan L, Styrishave B, Ciesielski TM, Peng WX, and Sonne C

Subjects
Mice, Animals, Humans, Hep G2 Cells, Cell Line, Tumor, Mice, Nude, Apoptosis, Carcinoma, Hepatocellular drug therapy, Liver Neoplasms drug therapy, Antineoplastic Agents pharmacology, Antineoplastic Agents therapeutic use
Abstract

Here, we collected 154 plant species in China ancient forests looking for novel efficient bioactive compounds for cancer treatments. We found 600 bioactive phyto-chemicals that induce apoptosis of liver cancer cell in vitro. First, we screen the plant extract's in vitro cytotoxicity inhibition of cancer cell growth using in vitro HepG2 cell lines and MTT cytotoxicity. The results from these initial MTT in vitro cytotoxicity tests show that the most efficient plants towards hepatoma cytoxicity is Cephalotaxus sinensis, mint bush (Elsholtzia stauntonii) and winged spindle tree (Euonymus alatus). We then used in cell-counting kit-8 (CCK-8) to further understand in vivo tumor growth using nude mice and GC-MS and LC-QTOF-MS to analyze the composition of compounds in the extracts. Extracted chemically active molecules analyzed by network pharmacology showed inhibition on the growth of liver cancer cells by acting on multiple gene targets, which is different from the currently used traditional drugs acting on only one target of liver cancer cells. Extracts from Cephalotaxus sinensis, mint bush (Elsholtzia stauntonii) and winged spindle tree (Euonymus alatus) induce apoptosis in hepatoma cancer cell line HepG2 with a killing rate of more than 83% and a tumor size decrease by 62-67% and a killing rate of only 6% of normal hepatocyte LO2. This study highlight efficient candidate species for cancer treatment providing a basis for future development of novel plant-based drugs to help meeting several of the UN SDGs and planetary health., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Published
2024
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47. Electrospun microcrystalline cellulose/chitosan porous composite nanofibrous membranes modified by non-thermal plasma for gaseous formaldehyde adsorption.

Author

Xiong J, Luo R, Jia Z, Ge S, Lam SS, Xie L, Chai X, Zhang L, Du G, Wang S, and Xu K

Subjects
Gases, Adsorption, Porosity, Formaldehyde chemistry, Nitrogen, Nanofibers chemistry, Chitosan chemistry, Cellulose
Abstract

To develop a green and facile adsorbent for removing indoor polluted formaldehyde (HCHO) gas, the biomass porous nanofibrous membranes (BPNMs) derived from microcrystalline cellulose/chitosan were fabricated by electrospinning. The enhanced chemical adsorption sites with diverse oxygen (O) and nitrogen (N)-containing functional groups were introduced on the surface of BPNMs by non-thermal plasma modification under carbon dioxide (CO 2 ) and nitrogen (N 2 ) atmospheres. The average nanofiber diameters of nanofibrous membranes and their nanomechanical elastic modulus and hardness values decreased from 341 nm to 175-317 nm and from 2.00 GPa and 0.25 GPa to 1.70 GPa and 0.21 GPa, respectively, after plasma activation. The plasma-activated nanofibers showed superior hydrophilicity (WCA = 0°) and higher crystallinity than that of the control. The optimal HCHO adsorption capacity (134.16 mg g -1 ) of BPNMs was achieved under a N 2 atmosphere at a plasma power of 30 W and for 3 min, which was 62.42 % higher compared with the control. Pyrrolic N, pyridinic N, CO and O-C=O were the most significant O and N-containing functional groups for the improved chemical adsorption of the BPNMs. The adsorption mechanism involved a synergistic combination of physical and chemical adsorption. This study provides a novel strategy that combines clean plasma activation with electrospinning to efficiently remove gaseous HCHO., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Published
2024
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48. A hidden demethylation pathway removes mercury from rice plants and mitigates mercury flux to food chains.

Author

Tang W, Bai X, Zhou Y, Sonne C, Wu M, Lam SS, Hintelmann H, Mitchell CPJ, Johs A, Gu B, Nunes L, Liu C, Feng N, Yang S, Rinklebe J, Lin Y, Chen L, Zhang Y, Yang Y, Wang J, Li S, Wu Q, Ok YS, Xu D, Li H, Zhang XX, Ren H, Jiang G, Chai Z, Gao Y, Zhao J, and Zhong H

Subjects
Infant, Newborn, Humans, Food Chain, Demethylation, Mercury metabolism, Oryza metabolism, Methylmercury Compounds metabolism
Abstract

Dietary exposure to methylmercury (MeHg) causes irreversible damage to human cognition and is mitigated by photolysis and microbial demethylation of MeHg. Rice (Oryza sativa L.) has been identified as a major dietary source of MeHg. However, it remains unknown what drives the process within plants for MeHg to make its way from soils to rice and the subsequent human dietary exposure to Hg. Here we report a hidden pathway of MeHg demethylation independent of light and microorganisms in rice plants. This natural pathway is driven by reactive oxygen species generated in vivo, rapidly transforming MeHg to inorganic Hg and then eliminating Hg from plants as gaseous Hg°. MeHg concentrations in rice grains would increase by 2.4- to 4.7-fold without this pathway, which equates to intelligence quotient losses of 0.01-0.51 points per newborn in major rice-consuming countries, corresponding to annual economic losses of US$30.7-84.2 billion globally. This discovered pathway effectively removes Hg from human food webs, playing an important role in exposure mitigation and global Hg cycling., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)

Published
2024
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49. Early Postoperative Aqueous Suppression Therapy and Surgical Outcomes of Ahmed Tube Shunts in Refractory Glaucoma.

Author

Shalaby WS, Wong JC, Zhang TZ, Hallaj S, Lam SS, Dale EA, Pro MJ, Kolomeyer NN, Shukla AG, Lee D, Myers JS, Razeghinejad R, and Moster MR

Subjects
Humans, Retrospective Studies, Treatment Outcome, Follow-Up Studies, Glaucoma Drainage Implants, Glaucoma
Abstract

Purpose: To compare early vs. delayed use of aqueous suppressants on Ahmed glaucoma valve (AGV) outcomes., Design: Single-center retrospective comparative case series., Participants: Patients who underwent AGV surgery at Wills Eye Hospital in the period between 2016 and 2021., Methods: Retrospective review of AGV surgery at Wills Eye Hospital 2016 to 2021 for refractory glaucoma. Two groups were created: group 1 or those who received early aqueous suppressant therapy in the first 2 weeks postoperatively whenever the intraocular pressure (IOP) was > 10 mmHg, and group 2 or those who received delayed treatment after 2 weeks whenever the IOP exceeded the target pressure. Aqueous suppressant therapy included topical beta blockers, carbonic anhydrase inhibitors, and/or alpha agonists., Main Outcome Measures: The primary outcome measures were the frequency of hypertensive phase (HP) defined as IOP > 21 mmHg in first 3 months after an initial reduction to 21 mmHg or less in the first postoperative week not caused by tube obstruction or retraction, and month-12 surgical failure defined as 5 ≥ IOP > 21 mmHg on 2 consecutive visits, vision decline to no light perception (NLP), or glaucoma reoperation. Secondary outcome measures included changes in visual acuity (VA), IOP, and glaucoma medications at 12 months. Predictive factors for surgical failure were also identified., Results: A total of 407 eyes of 391 patients (260 in group 1, 147 in group 2) with similar baseline characteristics were included. Hypertensive phase was more common in group 2 than 1 (41.5% vs. 18.5%; P < 0.001). At month 12 (N = 303 eyes), group 1 was less likely to fail than group 2 (21.2% vs. 36.8%, P = 0.003). Multivariate regression analysis showed that HP (odds ratio [OR] = 10.47, P < 0.001), delayed aqueous suppression use (OR = 2.17, P = 0.003), and lower baseline VA (OR = 1.56, P = 0.015) were the strongest predictors of month-12 failure., Conclusions: Early use of aqueous suppressants may lower the risk of HP and improve AGV outcomes., Financial Disclosure(s): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article., (Copyright © 2023 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Published
2024
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50. Protect the oceans from Japan's radioisotope dumping.

Author

Li C, Zhong H, Meng L, Wu M, Ning W, Lam SS, Luo J, and Sonne C

Abstract

•Dumping of Fukushima's radioactive wastewater raises marine food web concern.•Tritium seems to be the most problematic compound.•Long-lived radioisotopes Biomagnify up to 50,000 folds in marine fish species.•This threatens fragile deep-sea ecosystems requiring immediate action.•Empowered Routine monitoring is crucial to maintain planetary health., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)

Published
2023
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