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The study investigated the performance of a novel magnetic hybrid MIL-53(Fe)/Fe3O4@TiO2 composite for removing reactive red 195 (RR195) dye from water using UVc light. Various analytical techniques were used to characterize the nanocomposite materials. X-ray diffraction analysis confirmed the presence of MIL-53(Fe) and TiO2 in the composite. FT-IR analysis identified carboxyl and Ti-O-Ti groups in the photocatalyst structure. The study evaluated the effects of pH, dye concentration, photocatalyst dosage, and temperature on RR195 photodegradation. The Langmuir-Hinshelwood kinetic model provided the best fit for the reaction rate. Optimal conditions for an 84 % dye degradation were found at a photocatalyst dose of 15 mg/100 mL, pH 3, dye concentration of 100 mg/L, and 35 °C after 120 minutes of UVc light exposure. Thermodynamic analysis indicated an endothermic reaction with positive values for Δ#H and negative values for Δ#S. The MIL-53(Fe)/Fe3O4@TiO2 composite demonstrated excellent stability and achieved over 90 % dye degradation after five cycles. Overall, the composite shows promise for treating wastewater with dyes.

Biomass wastes, such as agricultural residues from rice field are generated in a large amount. Hydrothermal carbonization (HTC) treatment can convert biomass wastes into value-added product known as hydrochar, which gained researchers interests for various environmental applications. However, recent studies have shown inconsistent results for the use of hydrochar on crop production and soil improvement. Thus, the aim of this study is to understand the characteristics and potential use of rice husk and rice straw hydrochar as soil amendment. Two types of hydrochar (RHH: rice husk hydrochar, and RSH: rice straw hydrochar) produced using HTC at a pressure of 1.6 MPa, temperature at 160 – 180 °C, and reaction time of 30 min, were used to conduct pot experiment. Nutrients and morphological study of hydrochar and its raw biomass were analyzed. Five treatments (0 % hydrochar as control, 1 % RHH, 10 % RHH, 1 % RSH, and 10 % RSH (w/w)) were applied in commercial garden soil to observe the effects on soil pH and Spinach plant growth. The result from this study shows that HTC have significant effects on the hydrochar properties. The hydrochars have coarser surface and several microstructures formed on the surface. HTC significantly decreased pH, increased moisture content, and altered the nutrient compositions of the biomass. Pot experiment results showed that all hydrochar-amended treatments decreased soil pH below optimal pH of 6.0, which causes the decreased plant biomass by 60 – 67 % compared to control. This shows that these hydrochars are useful as soil amendment for dry degraded soils with pH =8. Further research is needed to reveal the mechanisms and potential modification required before using the hydrochar as soil amendment.

Banana peels serve as a valuable fiber source with considerable potential for formulation of animal feed. Although it has high fibre content, lignocellulosic fibres caused low digestibility for ruminants and susceptibility of banana peels to spoilage imposes limitations on their utilization. This study highlights the use of subcritical water technology as a pretreatment to enhance nutritional value of banana peels and prolong their shelf life as ingredients in ruminant feed pellet. The proximate analysis of treated banana peels (SCW-BP) contains 6.9 ± 0.07% of crude fat, 47.3 ± 0.06% of crude fibre and 10.6 ± 0.07% crude protein. In order to produce balanced nutritional diet for ruminant feed, 54% of SCW-BP was mixed with 46% of sorghum to attain 15% of crude protein by using Pearson square method. Thus, the formulated feed ingredients produced meets the nutrient required by the ruminants.

Municipal solid waste management (MWM) in Malaysia has become a challenging task in recent years due to the growth of population, industrialization and an increase in quantity and variation in the types of waste generated. Major solid waste generated in Malaysia is organic waste which includes mainly food waste from households, food processing facilities, markets, food and beverages industry and hospitals. Therefore, it is crucial to identify ways to manage food waste (FW) properly and improve the energy recovery efficiency. This paper is aimed to study the impact of pre-treatment on food waste from Hospital Pakar Sultanah Fatimah (HPSF) as a method to decompose FW faster and to determine the potential of bio-methane generation. A compositional study showed that total solid waste generated was 2,301 kg with 67% waste from lunch followed by 31% from breakfast sessions daily. Hydrothermal pre-treatment was done using a Multipurpose Recycling Machine (MRM) at 1.6MPa for 15 minutes followed by anaerobic digestion with and without the inoculum addition. Un-treated FW with inoculum was used as control in this experiment. It was found out that at a controlled pH of 7, hydrothermal pre-treatment and addition of inoculum i.e. cow manure played an important role in anaerobic digestion process for enhancement of bio-methane production. It significantly reduced the lag phase by 4 days and produced biogas faster compared to nontreated FW and hence, increased the biogas volume up to 638.53 mL compared to 504.08 mL in non-treated FW at the same experimental conditions. Therefore, this study signified that hydrothermal pretreatment is an effective and a beneficial technique added to the waste through the generation of biogas energy.

The main objective of the present work is to investigate the thermal degradation behaviour of the non-catalytic and catalytic co-pyrolysis of empty fruit bunch (EFB) and high-density polyethylene (HDPE) over commercial hydrogen exchanged zeolite socony mobil five (HZSM-5) and rice husk ash (RHA) catalysts via thermogravimetric analyser (TGA). RHA catalysts were produced using the solvent-free method by converting RHA into HZSM-5. XRD characterization was conducted for the synthesized catalysts and RHA catalyst showed less amount of peaks compared to commercial HZSM-5. Non-catalytic and catalytic co-pyrolysis of EFB and HDPE over commercial HZSM-5 and RHA catalysts were conducted using TGA. A fixed EFB-to-HDPE mass ratio of 1:1 and a fixed catalyst-to-feedstock mass ratio of 1:1 were used for the TGA experiments. The sample was heated up under pyrolysis conditions at a heating rate of 20 °C/min until 700 °C. The thermal degradation behaviour of EFB and HDPE did not change significantly when RHA catalysts were used, based on the TG curves. Volatilization of matter was maximum between temperatures 240 °C and 500 °C (Phase II) for all cases of the pyrolysis process, where the highest volatilized matter of 93.2 wt% was produced from the catalytic process over commercial HZSM-5, followed by the catalytic process over RHA catalysts with 92.3 wt% of volatilized matter and non-catalytic process with 83.0 wt% of volatilized matter. When using catalysts, 0.44 wt% of solid residual was left when commercial HZSM-5 was used while 0.38 wt% of solid residual was left when RHA catalyst was used.

The palm oil industry generates a high amount of residues during their processing. Empty fruit bunches (EFB) is one of the biomass which can be utilised for bioethanol production. In this study, life cycle assessment (LCA) with the cradle-to-gate approach is performed with the help of SimaPro version 9.0, whereby four impact categories are evaluated. The economic performance of the production is analysed through life cycle costing (LCC). The scope is from palm tree cultivation to refined bioethanol production. In LCC, specific cost data such as raw material costs, labour and capital expenditure, operational costs, and transport costs will be considered. The LCC is 562.44 MYR/t of bioethanol with an annual profit of 5.50 × 108 MYR/y and a payback period of 0.51 y. From an environmental view, the significant contributors to the environmental impacts are agriculture and the pretreatment process. From an economic perspective, the chemical cost is the most burden cost in the upstream process. In contrast, the cost of the raw materials is the main contributor to the bioethanol production cost. The environmental impacts and cost burden can be reduced by cutting down the usage of chemicals.

According to Malaysia National Greenhouse Gas Inventory report, a total of 67,532 Gg CO2eq of methane was emitted in year 2011. The highest methane emission was from the solid waste disposal sites, which accounted for about 46 % from the total which remained the largest source throughout the time series period. Proper gas monitoring was not done in most landfills which the emission trend, pattern and impact remains untold. Understanding methane and carbon dioxide concentration trends will positively help in spatial variation of land?ll emissions in Malaysia. Therefore, this research highlighted two objectives. First, to test feasibility of prototype sampling tube to collect gas samples. Second, to analyze gas samples using micro gas chromatography and evaluate emission trend in Taman Beringin Closed Landfill. Using proper technique, the sampling tube was employed manually at the gas well which located at the highest point of the hill. Three samples collected everyday between 12 to 2 p.m. for 1 mth. Result shows an interesting trend recorded for methane and carbon dioxide. Though the concentrations vary for each day, it highlighted certain range in the graph. Methane ranging between 550,000 ppm to 850,000 ppm and carbon dioxide ranging between 400,000 ppm to 620,000 ppm. It is high concentration emitted everyday considering maximum recommended safe methane concentration for workers during an 8-h period is 1,000 ppm (0.1 %) as stated by National Institute for Occupational Safety and Health's (NIOSH) and Occupational Safety and Health Administration (OSHA) has set a Permissible Exposure Limit (PEL) for carbon dioxide of 5,000 ppm by volume (0.5 % concentration). In addition, T-test was done to statistically shows the significant different between samples collected and the permissible standard. Result shows significant high concentration emitted compared to the safe level allowable in ambient air. This study helps addressing gap in landfills greenhouse emission monitoring in Malaysia.

The study investigated the performance of a novel magnetic hybrid MIL-53(Fe)/Fe 3 O 4 @TiO 2 composite for removing reactive red 195 (RR195) dye from water using UVc light. Various analytical techniques were used to characterize the nanocomposite materials. X-ray diffraction analysis confirmed the presence of MIL-53(Fe) and TiO 2 in the composite. FT-IR analysis identified carboxyl and Ti-O-Ti groups in the photocatalyst structure. The study evaluated the effects of pH, dye concentration, photocatalyst dosage, and temperature on RR195 photodegradation. The Langmuir-Hinshelwood kinetic model provided the best fit for the reaction rate. Optimal conditions for an 84 % dye degradation were found at a photocatalyst dose of 15 mg/100 mL, pH 3, dye concentration of 100 mg/L, and 35 °C after 120 minutes of UVc light exposure. Thermodynamic analysis indicated an endothermic reaction with positive values for Δ#H and negative values for Δ#S. The MIL-53(Fe)/Fe 3 O 4 @TiO 2 composite demonstrated excellent stability and achieved over 90 % dye degradation after five cycles. Overall, the composite shows promise for treating wastewater with dyes. [Display omitted] • A novel metal-organic framework photocatalyst, MIL-53(Fe)/Fe 3 O 4 @TiO 2 , was made using a solvothermal synthesis process. • Under optimal conditions, 84 % of Reactive Red 195 dye (RR195) was degraded within 2 h. • Our hybrid nanocomposite has great potential for pollution remediation, enhanced efficiency, and improved recyclability [ABSTRACT FROM AUTHOR]

Toxicity induced by heavy metals deteriorates soil fertility status. It also adversely affects the growth and yield of crops. These heavy metals become part of the food chain when crops are cultivated in areas where heavy metals are beyond threshold limits. Cadmium (Cd) and nickel (Ni) are considered the most notorious ones among different heavy metals. The high water solubility of Cd made it a potential toxin for plants and their consumers. Accumulation of Ni in plants, leaves, and fruits also deteriorates their quality and causes cancer in humans when such a Ni-contaminated diet is used regularly. Both Cd and Ni also compete with essential nutrients of plants, making the fertility status of soil poor. To overcome this problem, the use of activated carbon biochar can play a milestone role. In the recent past application of activated carbon biochar is gaining more and more attention. Biochar sorb the Cd and Ni and releases essential micronutrients that are part of its structure. Many micropores and high cation exchange capacity make it the most acceptable organic amendment to improve soil fertility and immobilize Cd and Ni. In addition to improving water and nutrients, soil better microbial proliferation enhances the soil rhizosphere ecosystem and nutrient cycling. This review has covered Cd and Ni harmful effects on crop yield and their immobilization by activated carbon biochar. The focus was made to elaborate on the positive effects of biochar on crop yield and soil health. [ABSTRACT FROM AUTHOR]

The study investigated the performance of a novel magnetic hybrid MIL-53(Fe)/Fe 3 O 4 @TiO 2 composite for removing reactive red 195 (RR195) dye from water using UVc light. Various analytical techniques were used to characterize the nanocomposite materials. X-ray diffraction analysis confirmed the presence of MIL-53(Fe) and TiO 2 in the composite. FT-IR analysis identified carboxyl and Ti-O-Ti groups in the photocatalyst structure. The study evaluated the effects of pH, dye concentration, photocatalyst dosage, and temperature on RR195 photodegradation. The Langmuir-Hinshelwood kinetic model provided the best fit for the reaction rate. Optimal conditions for an 84 % dye degradation were found at a photocatalyst dose of 15 mg/100 mL, pH 3, dye concentration of 100 mg/L, and 35 °C after 120 minutes of UVc light exposure. Thermodynamic analysis indicated an endothermic reaction with positive values for Δ # H and negative values for Δ # S. The MIL-53(Fe)/Fe 3 O 4 @TiO 2 composite demonstrated excellent stability and achieved over 90 % dye degradation after five cycles. Overall, the composite shows promise for treating wastewater with dyes., 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 The Authors. Published by Elsevier Inc. All rights reserved.)

In this study, an attempt was made to synthesize metal-organic frameworks (MOFs) based magnetic iron particles as photocatalysts for textile dye wastewater. Improvement strategy was a novel two-step dry method without using conventional methods to eliminate the consumption of chemical reagents. First, the heterogeneous photocatalyst of Fe-MOFs derived magnetic carbon nanocomposite with carboxylic acid surface functional groups (Fe@C-COOH) was achieved. Next, the α-Fe 2 O 3 @C@SiO 2 /TiO 2 was successfully synthesized followed by a sol-gel method to coat the SiO 2 shell and a solvothermal method to coat the surface of the intermediate TiO 2 particles. The as-synthesized nanocomposite materials were characterized and physicochemical analytical equipment. Further, the investigation on magnetic photocatalytic nanocomposite α-Fe 2 O 3 @C@SiO 2 /TiO 2 performance of dye degradation and photocatalytic activity on Reactive yellow 145 (RY145), using as an indicator was conducted. The as-synthesized nanocomposite particles were characterized using X-ray powder diffraction (XRD), thermogravimetric analysis (TGA), Fourier-transform infrared spectroscopy (FT-IR), vibrating sample magnetometer (VSM), X-ray energy dispersive spectroscopy (EDX), and scanning electron microscopy (SEM) techniques. The structural characterization of the as-synthesized materials proved that these methods generate oxygen-containing functional groups, such as, -OH, -CO, and -COOH, which increases the polarity and hydrophilicity of the photocatalyst. The photocatalytic oxidation of RY145 dye under UVc light was discussed by the apparent first-order reaction rate and the kinetic model of the Langmuir-Hinshelwood followed a better fitting. The optimal performance of the composite is at pH = 2, 15 mg/100 mL of photocatalyst dose, 150 mg/L concentration of the dye RY145 at 25 °C temperature under UVc lamp irradiation for 90 min, and with the apparent reaction rate constant was 0.0165 min -1 . The thermodynamic analysis of activation parameters computed by the Eyring model and based on transition state theory (TST), an endothermic reaction with a positive value for Δ ‡ H o (50.16 kJ mol -1 ) and a negative value for Δ ‡ S o (-153 J/mol K) both contribute toward achieving positive values for Δ ‡ G o and a nonspontaneous process. The proposed α-Fe 2 O 3 @C@SiO 2 /TiO 2 demonstrated a high capability of photocatalytic degradation up to 97% after five successive cycles at the optimal condition compared to that of Fe 3 O 4 @C (18.74%) and Fe@C-COOH (77.9%) without reusability., (Copyright © 2022 Elsevier Ltd. All rights reserved.)