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Biodiesel (methyl esters) has been produced using numerous catalysts to enhance its quality and related productivity. Generally, the raw materials for biodiesel production and its catalysts significantly impact the produced biodiesel's quality. In addition, the heterogeneous catalysts are promising as catalysts in the transesterification for biodiesel production and can be used continuously during this production. In particular, these catalysts are essential for green biodiesel production because of their high activity, thermal stability, and reusability. Hence, several homogeneous and heterogeneous (acidic and alkaline) catalysts for biodiesel production, particularly the naturally derived heterogeneous catalysts, are reviewed in this article. Further, the different heterogeneous catalysts for biodiesel production have been studied extensively as replacements for the respective homogeneous catalyst. Specifically, this replacement is aimed at the simultaneous esterification and transesterification of the nonedible and low-cost biomasses under moderate conditions producing biodiesel. Moreover, this study analyzes biodiesel's impact and long-term performance in various applications. Finally, it also reports the advancements in biodiesel production in terms of the catalysts used in it and its processes to aid further developments in biodiesel production. [ABSTRACT FROM AUTHOR]

The contamination of ecosystems by pharmaceuticals and personal care products represents a significant threat to public health, necessitating innovative approaches to clean wastewater before release into aquatic environments. Here, we review the emerging strategies and methods for the remediation of gemfibrozil and carbamazepine, emphasizing toxicological impacts, advanced oxidation processes, membrane-based removal techniques, and the underlying mechanisms driving these removal processes. We found that engineered composites with strong electron transfer capabilities can enhance the removal efficiency as they boost the generation of highly oxidative radicals. For instance, a nano zero-valent ion incorporated carbon–nitrogen composite removes 100% of gemfibrozil within 60 min. Similarly, a ruthenium perovskite-based heterogeneous catalyst achieved 100% elimination of carbamazepine in 7.5 min. [ABSTRACT FROM AUTHOR]

Hydrocarbons (fuel) derived from agricultural waste biomass are potential alternatives, and these hydrocarbons are within range of jet fuel and diesel. In the current research work, date seeds are considered a feedstock for bio-oil (composed of oxygenated hydrocarbons) and is subjected to hydro-deoxygenation to produce green jet fuel and diesel. Hydro-deoxygenation is exothermic reaction and involves cracking for which a novel heterogeneous catalyst is synthesised. The heterogeneous catalyst consists of an acidic nature precursor derived from waste glass (SiO2) and active metals (tungsten, nickel and palladium) to provide the acidic sites for better-desired product yield. The synthesised catalysts are characterised in detail by the following techniques X-ray diffraction analysis (XRD), Scanning electron microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDXS), Brunauer–Emmett–Teller (BET), Ammonia-Temperature programmed desorption (TPD) and X-ray Photoelectron Spectroscopy (XPS) and based on characterisation it is revealed that synthesised will be suitable for hydro-deoxygenation. The most appropriate combination of metal and precursor is Pd-SiO2. Product oil's optimised degree of deoxygenation (DOD) is found to be 93.7% with the following parameters: temperature 340 °C, time 4 h and 4 wt.% of Pd on SiO2. Further on, to prove the commercial viability of the catalyst, it was subjected to five consecutive experimental runs, and it was much active till 5th run if treated before each run. Thus, it can be concluded that bio-oil source is agricultural waste, and for catalyst precursor waste glass is considered; so by considering these factors, the product oil produced has components which lie within the range of jet fuel and diesel, which can be economical as well as eco-friendly source of fuel. [ABSTRACT FROM AUTHOR]

The excessive reliance on fossil fuels has resulted in an energy crisis, environmental pollution, and health problems, calling for alternative fuels such as biodiesel. Here, we review computational chemistry and machine learning for optimizing biodiesel production from waste. This article presents computational and machine learning techniques, biodiesel characteristics, transesterification, waste materials, and policies encouraging biodiesel production from waste. Computational techniques are applied to catalyst design and deactivation, reaction and reactor optimization, stability assessment, waste feedstock analysis, process scale-up, reaction mechanims, and molecular dynamics simulation. Waste feedstock comprise cooking oil, animal fat, vegetable oil, algae, fish waste, municipal solid waste and sewage sludge. Waste cooking oil represents about 10% of global biodiesel production, and restaurants alone produce over 1,000,000 m3 of waste vegetable oil annual. Microalgae produces 250 times more oil per acre than soybeans and 7–31 times more oil than palm oil. Transesterification of food waste lipids can produce biodiesel with a 100% yield. Sewage sludge represents a significant biomass waste that can contribute to renewable energy production. [ABSTRACT FROM AUTHOR]

In the pursuit of sustainable energy solutions, hydrogen emerges as a promising candidate for decarbonization. The United States has the potential to sell wind energy at a record‐low price of 2.5 cents/kWh, making hydrogen production electricity up to four times cheaper than natural gas. Hydrogen's appeal stems from its highly exothermic reaction with oxygen, producing only water as a byproduct. With an energy content equivalent to 2.4 kg of methane or 2.8 kg of gasoline per kilogram, hydrogen boasts a superior energy‐to‐weight ratio compared to fossil fuels. However, its energy‐to‐volume ratio, exemplified by liquid hydrogen's 8.5 MJ.L−1 versus gasoline's 32.6 MJ.L−1, presents a challenge, requiring a larger volume for equivalent energy. In addition, this review employs life cycle assessment (LCA) to evaluate hydrogen's full life cycle, including production, storage, and utilization. Through an examination of LCA methodologies and principles, the review underscores its importance in measuring hydrogen's environmental sustainability and energy consumption. Key findings reveal diverse hydrogen production pathways, such as blue, green, and purple hydrogen, offering a nuanced understanding of their life cycle inventories. The impact assessment of hydrogen production is explored, supported by case studies illustrating environmental implications. Comparative LCA analysis across different pathways provides crucial insights for decision‐making, shaping environmental and sustainability considerations. Ultimately, the review emphasizes LCA's pivotal role in guiding the hydrogen economy toward a low‐carbon future, positioning hydrogen as a versatile energy carrier with significant potential. This article is categorized under:Emerging Technologies > Hydrogen and Fuel Cells [ABSTRACT FROM AUTHOR]

This study explores the sustainable production of biodiesel from nonedible Phyllanthus maderaspatensis seed oil (highest oil content of 35%, FFA 0.87 mg/KOH), utilizing an innovative green synthesis approach for chromium oxide nanoparticles derived from the waste fruit parts of Aubergine for the very first time in the current work. In pursuit of alternatives to fossil fuels, our research underscores the environmental and socio‐economic benefits of biofuels, particularly in reducing greenhouse gas emissions. The optimized process yielded a 92% biodiesel conversion under conditions of a 9:1 methanol‐to‐oil ratio, 0.135 wt.% catalyst concentration, and a reaction duration of 150 min at 80°C. Comprehensive analysis techniques, including XRD, FTIR, SEM, EDX, Zeta analysis, differential reflectance spectroscopy (DRS), GC–MS, and NMR (1H, 13C), were employed to characterize the synthesized nanocatalyst and biodiesel product. The biodiesel's fuel properties, such as acid value, fire point, pour point, viscosity, kinematic density, sulfur content, and cloud point, were rigorously tested, demonstrating compliance with international standards (ASTM D‐6571, EN 14214, and GB/T 20828‐2007). The use of P. maderaspatensis seed oil, an economical and environmentally friendly feedstock, in conjunction with a cost‐effective nanocatalyst, presents a viable pathway for the sustainable and scalable production of biodiesel. This study contributes to the advancement of bioproducts for a sustainable bioeconomy by demonstrating an integrated approach to bioenergy production that leverages biotechnological innovations and addresses both environmental and socio‐economic dimensions. [ABSTRACT FROM AUTHOR]

The complex catalyst synthesis procedure is always a hurdle in the industrialization of catalysts. Industry eagerly needs catalysts for the dry reforming of methane, which can be prepared through straightforward, cheap processes by semi-skilled workers. Herein, dual metal oxide support 10 wt% MOx (M = Ti, Si, Zr, Y) & 90 wt% Al2O3 is prepared by just mixing mechanically and thereafter, catalytic active 5 wt% Ni is dispersed over the support by impregnation method. Metal oxide pairs in ZrO2 + Al2O3, TiO2-Al2O3, SiO2 + Al2O3, and Y2O3 + Al2O3 supports are non-interacting, partially-interacting, significantly interacting (through Si–O–Al) and highly interacting (with maximum covalence character) respectively. Ni dispersed over SiO2 + Al2O3 or Y2O3 + Al2O3 supports are strongly interacted, whereas Ni/Y2O3 + Al2O3 catalyst has oxide enrichment over the surface for potential oxidation of carbon deposit. The interacting nature of metal oxide pair in support, stability of active sites and extent of oxide enrichment over the surface confirms the following order of coke deposition, Ni/Y2O3 + Al2O3 (8%) < Ni/SiO2 + Al2O3 (17%) < Ni/TiO2-Al2O3 (38.2%) < Ni/ZrO2 + Al2O3 (52.3%), as well as reverse order of catalytic activity, Ni/Y2O3 + Al2O3 (60%) > Ni/SiO2 + Al2O3 (55%) > Ni/TiO2-Al2O3 (50%) > Ni/ZrO2 + Al2O3 (47%). [ABSTRACT FROM AUTHOR]

The textile industry is water intensive and discharges numerous coloring compounds into the water body that depend on the industry's geographical location, the wet processes used for manufacturing, processing conditions, and the substrates involved. Textile wastewater contains chlorobenzenes, phthalates, heavy metals, azo dyes, and chlorophenols that have severe health issues, such as being allergenic, cytotoxic, genotoxic, mutagenic, and carcinogenic threats to living organisms. The differing concentrations of sulfates, chlorides, TOC, TDS, TSS, BOD, COD, high pH, and dye content characterize textile wastewater. To protect the environment and public health, a higher concentration of these items in textile wastewater is needed to treat the textile wastewater effluent before discharge. The conventional treatment methods are not able to fully remove the pollutants, such as physical treatments can only remove grease, oil, and TSS, whereas biological wastewater treatment (aerobic and anaerobic) can only decrease colors, COD, BOD, oil, and phenol with a higher accomplishment period and by-products. Therefore, it is necessary to develop effective ecofriendly, cost-effective, novel techniques, such as membrane technology, and a promising method with fewer by-products. The activated carbon method effectively removes heavy metals and dyes from the textile wastewater, and advanced oxidation processes (AOPs) are a recent development in textile wastewater treatment processes. Combining AOPs methods has been proven effective in removing pollutants when combined with biological and advanced physical processes. This paper reviews the textile manufacturing process, textile wastewater characteristics, textile wastewater's impact on the environment and health, and the available textile wastewater treatment approach. [ABSTRACT FROM AUTHOR]

The energy crisis and environmental pollution have recently fostered research on efficient methods such as environmental catalysis to produce biofuel and to clean water. Environmental catalysis refers to green catalysts used to breakdown pollutants or produce chemicals without generating undesirable by-products. For example, catalysts derived from waste or inexpensive materials are promising for the circular economy. Here we review environmental photocatalysis, biocatalysis, and electrocatalysis, with focus on catalyst synthesis, structure, and applications. Common catalysts include biomass-derived materials, metal–organic frameworks, non-noble metals nanoparticles, nanocomposites and enzymes. Structure characterization is done by Brunauer–Emmett–Teller isotherm, thermogravimetry, X-ray diffraction and photoelectron spectroscopy. We found that water pollutants can be degraded with an efficiency ranging from 71.7 to 100%, notably by heterogeneous Fenton catalysis. Photocatalysis produced dihydrogen (H2) with generation rate higher than 100 μmol h−1. Dihydrogen yields ranged from 27 to 88% by methane cracking. Biodiesel production reached 48.6 to 99%. [ABSTRACT FROM AUTHOR]

Chemical reactors are employed to produce several materials, which are utilized in numerous applications. The wide use of these chemical engineering units shows their importance as their performance vastly affects the production process. Thus, improving these units will develop the process and/or the manufactured material. Multi-objective optimization (MOO) with evolutionary algorithms (EA's) has been used to solve several real world complex problems for improving the performance of chemical reactors with conflicting objectives. These objectives are of different nature as they could be economy, environment, safety, energy, exergy and/or process related. In this review, a brief description for MOO and EA's and their several types and applications is given. Then, MOO studies, which are related to the materials' production via chemical reactors, those were conducted with EA's are classified into different classes and discussed. The studies were classified according to the produced material to hydrogen and synthesis gas, petrochemicals and hydrocarbons, biochemical, polymerization and other general processes. Finally, some guidelines are given to help in deciding on future research. [ABSTRACT FROM AUTHOR]

The comparatively greater cost of producing biodiesel in comparison to petroleum diesel is one of the key drawbacks. Eggshells and leftover chicken fat are examples of poultry wastes that can be used to produce biodiesel at a low cost as catalysts and oil, respectively. In this study, eggshell-derived CaO and its doping with sodium methoxide catalyst for enhancing catalytic activity was synthesized for the transesterification of waste chicken fat and characterized by FT-IR and XRD analyses. XRD studies confirmed the crystalline structure of the developed catalyst and doping of sodium with eggshell-derived CaO. The transesterification reaction was performed at different reaction parameters such as the catalyst loading, the methanol to oil ratio, the reaction temperature, and the reaction time. The biodiesel produced at the maximum yield was evaluated by gas chromatography mass spectrometry analysis. A maximum yield of 96% biodiesel was obtained with catalyst loading of 2 wt% of oil, as well as a methanol to oil ratio of 13:1 at 60 °C in 1 h. The output demonstrates that eggshell waste is a potentially accessible source of biomass-derived nano catalyst for the synthesis of biodiesel using chicken fat as a feedstock. [ABSTRACT FROM AUTHOR]

4 Commercial status of bioethanol dehydration to bioethylene Ethylene from ethanol dehydration was first produced on the commercial scale in 1913 at Elektrochemische Werke GmbH in Bitterfeld, Germany ([133]). The catalyst activity and product selectivity depends on the kind of alcohol, kind of catalyst and process conditions, while the trend of alcohol dehydration observed in this research work was as follows: 2-propanol > l-propanol > ethanol, in accordance with the relative stabilities of the corresponding carbenium ions. Keywords: bioethanol; bioethylene; catalyst; dehydration; techno-economic feasibility EN bioethanol bioethylene catalyst dehydration techno-economic feasibility 185 207 23 02/07/22 20220201 NES 220201 1 Introduction The rise in oil prices, environmental issues due to toxic emissions caused by the combustion of fossil fuel and depletion of fossil fuel resources have a demand for an alternative pathway to produce green energy from waste streams ([69]; [74]; [101]; [189]). Another possibility is that three processes can co-occur such as ethanol dehydration to ethylene, ethanol transformation to ether or ether dehydration to ethylene as shown in Figure 7 ([30]; [114]; [161]). 5 Pathways and mechanisms of bioethanol dehydration to bioethylene During the middle of the previous century, much work has been conducted by different researchers to study the reaction mechanism of ethanol conversion to ethylene by dehydration in the presence of various catalysts ([49]; [71]; [82]; [110]; [159]; [166]). [Extracted from the article]

Summary: The current research work reports the synthesis of highly efficient heterogeneous barium oxide with molybdenum oxide (BaO‐MoO2) catalysts for transesterification of Balanites aegyptiaca seed oil for biodiesel production. The synthesized catalysts are being characterized through several analytical techniques such as X‐ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X‐ray photoelectron spectroscopy (XPS), temperature‐programmed desorption (TPD) and Brunauer‐Emmett‐Teller (BET) to examine its suitability for biodiesel production. The biodiesel production process was optimized and optimum yield obtained was 97.8% using a set of optimum conditions such as methanol‐to‐oil molar ratio of 12, the processing time of 120 minutes, process temperature of 65°C and with catalyst loading of 4.5 wt%. Moreover, catalyst reusability was determined and it was found to be highly suitable for reuse with minimum loss of its activity. Further on, quality of the produced biodiesel was evaluated to show its suitability as fuel and its potential as an alternative to fossil diesel. [ABSTRACT FROM AUTHOR]

Using fossil fuels to meet energy demands has led to immense CO2 emissions, resulting in global warming. Efforts to capture CO2 and find renewable energy fuels have been a rapidly evolving field of science. Methanol has been widely investigated as a promising renewable fuel. In this study, three cases of renewable methanol production were evaluated to investigate the possibility of using methanol as a way of mitigating CO2 and simultaneously reducing the dependence on depleting fossil fuel resources. A rigorous techno-economic analysis of the three cases was performed to evaluate the cost-effectiveness and risk involved in the production of renewable methanol by considering the market price of non-renewable methanol as a benchmark. Overall, the results indicate that considering the current market price ($ 560 per Mt) of methanol, renewable methanol production is not cost-effective. Risk analysis results further indicate that the economic risk associated with the investigated designs is between 96–100%. However, a comparison based on environmental performance reveals that the base and integrated designs are 17.5–51.3% better than the non-renewable methanol. In contrast, a 100% renewable design produces zero direct emissions. Hydrogen production price and plant scale are identified as the two crucial parameters for determining the feasibility of the process. Although the production of renewable methanol involves high risk, policy implications are discussed in this regard to pave the way for future improvements. [ABSTRACT FROM AUTHOR]

The growing demand for energy resources and the increase in greenhouse gas (GHG) emissions has given biofuels a lot of attention. Liquid biofuels can be a significant alternative for the transport sector. Generally, biofuels are categorized into four generations based on the feedstock. This review reports the availability, economic feasibility, and potential of biofuel feedstock in global scenario. Feedstock for first‐generation biofuel comprises edible resources impacting the food supply. Second generation biofuels are based on different residual materials and nonedible fuel crops. Cost and technological limitations for commercialization hinders this option. Microalgae are the feedstock for third generation biofuels providing the highest yield compared to the other two generations. A scale‐up to commercial level is not possible as this requires further development. Genetically modified microorganisms are used as a feedstock for fourth generation biofuel production with the highest possible yield. Third and fourth generation biofuels have potential to replace fossil fuels. This review recommends certain suggestions for sustainable biofuel production. [ABSTRACT FROM AUTHOR]

The world is experiencing an energy crisis and environmental issues due to the depletion of fossil fuels and the continuous increase in carbon dioxide concentrations. Microalgal biofuels are produced using sunlight, water, and simple salt minerals. Their high growth rate, photosynthesis, and carbon dioxide sequestration capacity make them one of the most important biorefinery platforms. Furthermore, microalgae's ability to alter their metabolism in response to environmental stresses to produce relatively high levels of high-value compounds makes them a promising alternative to fossil fuels. As a result, microalgae can significantly contribute to long-term solutions to critical global issues such as the energy crisis and climate change. The environmental benefits of algal biofuel have been demonstrated by significant reductions in carbon dioxide, nitrogen oxide, and sulfur oxide emissions. Microalgae-derived biomass has the potential to generate a wide range of commercially important high-value compounds, novel materials, and feedstock for a variety of industries, including cosmetics, food, and feed. This review evaluates the potential of using microalgal biomass to produce a variety of bioenergy carriers, including biodiesel from stored lipids, alcohols from reserved carbohydrate fermentation, and hydrogen, syngas, methane, biochar and bio-oils via anaerobic digestion, pyrolysis, and gasification. Furthermore, the potential use of microalgal biomass in carbon sequestration routes as an atmospheric carbon removal approach is being evaluated. The cost of algal biofuel production is primarily determined by culturing (77%), harvesting (12%), and lipid extraction (7.9%). As a result, the choice of microalgal species and cultivation mode (autotrophic, heterotrophic, and mixotrophic) are important factors in controlling biomass and bioenergy production, as well as fuel properties. The simultaneous production of microalgal biomass in agricultural, municipal, or industrial wastewater is a low-cost option that could significantly reduce economic and environmental costs while also providing a valuable remediation service. Microalgae have also been proposed as a viable candidate for carbon dioxide capture from the atmosphere or an industrial point source. Microalgae can sequester 1.3 kg of carbon dioxide to produce 1 kg of biomass. Using potent microalgal strains in efficient design bioreactors for carbon dioxide sequestration is thus a challenge. Microalgae can theoretically use up to 9% of light energy to capture and convert 513 tons of carbon dioxide into 280 tons of dry biomass per hectare per year in open and closed cultures. Using an integrated microalgal bio-refinery to recover high-value-added products could reduce waste and create efficient biomass processing into bioenergy. To design an efficient atmospheric carbon removal system, algal biomass cultivation should be coupled with thermochemical technologies, such as pyrolysis. [ABSTRACT FROM AUTHOR]

Porous boron carbon nitride (BCN) is one of the exciting systems with unique electrochemical and adsorption properties. However, the synthesis of low‐cost and porous BCN with tunable porosity is challenging, limiting its full potential in a variety of applications. Herein, the preparation of well‐defined mesoporous boron carbon nitride (MBCN) with high specific surface area, tunable pores, and nitrogen contents is demonstrated through a simple integration of chemical polymerization of readily available sucrose and borane ammonia complex (BAC) through the nano‐hard‐templating approach. The bimodal pores are introduced in MBCN by controlling the self‐organization of BAC and sucrose molecules within the nanochannels of the template. It is found that the optimized sample shows a high specific capacitance (296 F g−1 at 0.5 A g−1), large specific capacity for sodium‐ion battery (349 mAg h−1 at 50 mAh g−1), and excellent CO2 adsorption capacity (27.14 mmol g−1 at 30 bar). Density functional theory calculations demonstrate that different adsorption sites (BC, BN, CN, and CC) and the large specific surface area strongly support the high adsorption capacity. This finding offers an innovative breakthrough in the design and development of MBCN nanostructures for energy storage and carbon capture applications. [ABSTRACT FROM AUTHOR]

Conventional methods to clean wastewater actually lead to incomplete treatments, calling for advanced technologies to degrade recalcitrant pollutants. Herein we review solar photo-oxidation to degrade the recalcitrant contaminants in industrial wastewater, with focus on photocatalysts, reactor design and the photo-Fenton process. We discuss limitations due to low visible-light absorption, catalyst collection and reusability, and production of toxic by-products. Photodegradation of refractory organics by solar light is controlled by pH, photocatalyst composition and bandgap, pollutant properties and concentration, irradiation type and intensity, catalyst loading, and the water matrix. [ABSTRACT FROM AUTHOR]

The rapid urbanization and industrialization is causing worldwide water pollution, calling for advanced cleaning methods. For instance, pollutant adsorption on magnetic oxides is efficient and very practical due to the easy separation from solutions by an magnetic field. Here we review the synthesis and performance of magnetic oxides such as iron oxides, spinel ferrites, and perovskite oxides for water remediation. We present structural, optical, and magnetic properties. Magnetic oxides are also promising photocatalysts for the degradation of organic pollutants. Antimicrobial activities and adsorption of heavy metals and radionucleides are also discussed. [ABSTRACT FROM AUTHOR]

Dihydrogen (H2), commonly named 'hydrogen', is increasingly recognised as a clean and reliable energy vector for decarbonisation and defossilisation by various sectors. The global hydrogen demand is projected to increase from 70 million tonnes in 2019 to 120 million tonnes by 2024. Hydrogen development should also meet the seventh goal of 'affordable and clean energy' of the United Nations. Here we review hydrogen production and life cycle analysis, hydrogen geological storage and hydrogen utilisation. Hydrogen is produced by water electrolysis, steam methane reforming, methane pyrolysis and coal gasification. We compare the environmental impact of hydrogen production routes by life cycle analysis. Hydrogen is used in power systems, transportation, hydrocarbon and ammonia production, and metallugical industries. Overall, combining electrolysis-generated hydrogen with hydrogen storage in underground porous media such as geological reservoirs and salt caverns is well suited for shifting excess off-peak energy to meet dispatchable on-peak demand. [ABSTRACT FROM AUTHOR]

Functionalized fullerene nanostructures are a distinct class of materials that exhibit the combined properties of both fullerene and nanostructures including excellent optoelectronic features, modified band edges, high electron affinity, fast charge transfer capabilities, and tunable structural and textural properties. These fascinating properties allow for their utilization in many applications such as polymer solar cells, photovoltaics, photocatalysis, photodynamic therapy, electrocatalysis, environmental remediation, and drug and gene delivery. Numerous synthesis methods and anchoring groups are employed for functionalized fullerenes with nanostructures by using convergent bottom‐up and top‐down strategies. The supramolecular self‐assembly and functionalization of fullerenes through robust chemistry approaches such as surface oxidation, grafting, polymer coating, doping of metals/nonmetal heteroatoms, noncovalent modification with 2D materials and nanoparticle attachment result in achieving fine control over its surface and bulk properties, including increased solubility, wettability, electron transport, acid–base properties, adsorption, electronic conductivity, and light absorption. This review analyzes the salient developments in the fabrication of nanostructured fullerenes and their functionalized derivatives for many applications including adsorption, catalysis, sensors, energy storage, solar cells, drug delivery, magnetic and superconducting devices. The contents of this review will allow the readers to cherish exciting possibilities and opportunities in field of functionalized nanofullerenes. [ABSTRACT FROM AUTHOR]

The global energy demand is projected to rise by almost 28% by 2040 compared to current levels. Biomass is a promising energy source for producing either solid or liquid fuels. Biofuels are alternatives to fossil fuels to reduce anthropogenic greenhouse gas emissions. Nonetheless, policy decisions for biofuels should be based on evidence that biofuels are produced in a sustainable manner. To this end, life cycle assessment (LCA) provides information on environmental impacts associated with biofuel production chains. Here, we review advances in biomass conversion to biofuels and their environmental impact by life cycle assessment. Processes are gasification, combustion, pyrolysis, enzymatic hydrolysis routes and fermentation. Thermochemical processes are classified into low temperature, below 300 °C, and high temperature, higher than 300 °C, i.e. gasification, combustion and pyrolysis. Pyrolysis is promising because it operates at a relatively lower temperature of up to 500 °C, compared to gasification, which operates at 800–1300 °C. We focus on 1) the drawbacks and advantages of the thermochemical and biochemical conversion routes of biomass into various fuels and the possibility of integrating these routes for better process efficiency; 2) methodological approaches and key findings from 40 LCA studies on biomass to biofuel conversion pathways published from 2019 to 2021; and 3) bibliometric trends and knowledge gaps in biomass conversion into biofuels using thermochemical and biochemical routes. The integration of hydrothermal and biochemical routes is promising for the circular economy. [ABSTRACT FROM AUTHOR]

Summary: Recently, the glycolipids biosurfactant materials have widely been utilized for many industrial applications due to their feasible surface activity, biodegradable as well as eco‐friendly nature. Even though many of the earlier studies have been reported on such kind of surfactants, in this study we focused on porous rocks‐like Fe2O3/C composites, which were magnificently synthesized from a novel tropical fruit biomass, using a glycolipid biosurfactant with high specific surface area of about 466.9 m2/g via a biofunctional single‐step thermochemical method. They could be applied as an adsorbent to adsorb the pharmaceutical pollutants mainly, DCF from aqueous solution. Moreover, the highest adsorption capacity for DCF could be achieved, which is of about 77.51 mg/g. Furthermore, as‐prepared glycolipid functionalized Fe2O3/C composites were used as electrode materials for high‐performance supercapacitors. Galvanostatic charge‐discharge results showed that the Fe2O3/C modified electrode possesses a specific capacitance of about 374 F/g with a current density of 0.2 A/g and it has retained 84% of capacitance, even after 3000 cycles. The remarkable performances are mainly due to the surface amendments of the Fe2O3/C composite, using biologically produced glycolipid surfactant, would have more favorable foreground towards the upcoming energy crises. [ABSTRACT FROM AUTHOR]

Herein, cotton stalk biomass was initially characterized to understand its physicochemical properties as a raw material for biochar production. Furthermore, thermal analysis was conducted using thermogravimetric analysis (TGA), and the results were further utilized to evaluate the cotton stalk's kinetic behavior under thermal decomposition in an inert environment. Advanced kinetics and technology solutions (AKTS) software was for the first time employed to compute the kinetic parameters of cotton stalk pyrolysis, as well as provide kinetic predictions under isothermal conditions. Three methods were used to compute the activation energy (Ea) value, namely ASTM‐E698, Flynn‐Wall‐Ozawa (FWO), and Friedman's differential iso‐conversional model. The results obtained using the ASTM‐E698 method indicate an activation energy of 127.23 kJ·mol−1. Furthermore, the FWO method presented an Ea value ranging 35‐250 kJ·mol−1. The differential iso‐conversional method is the most robust approach as it adequately represents the complex nature of lignocellulosic biomass decomposition, showing an Ea range between 4 and 250 kJ·mol−1. Based on the differential iso‐conversional method, kinetic predictions under isothermal conditions were provided. The predictions offer valuable insight for industrial‐scale biochar project developers in relation to production throughput optimization. Furthermore, the kinetic parameters obtained can be utilized in process modeling. [ABSTRACT FROM AUTHOR]

The world is currently facing critical water and energy issues due to the growing population and industrialization, calling for methods to obtain potable water, e.g., by photocatalysis, and to convert solar energy into fuels such as chemical or electrical energy, then storing this energy. Energy storage has been recently improved by using electrochemical capacitors and ion batteries. Research is actually focusing on the synthesis of materials and hybrids displaying improved electronic, physiochemical, electrical, and optical properties. Here, we review molybdenum disulfide (MoS2) materials and hybrids with focus on synthesis, electronic structure and properties, calculations of state, bandgap and charge density profiles, and applications in energy storage and water remediation. [ABSTRACT FROM AUTHOR]

Mesoporous carbon nitrides with C3N5 and C3N6 stoichiometries created a new momentum in the field of organic metal‐free semiconductors owing to their unique band structures and high basicity. Here, we report on the preparation of a novel graphitic microporous carbon nitride with a tetrazine based chemical structure and the composition of C3N5.4 using ultra‐stable Y zeolite as the template and aminoguanidine hydrochloride, a high nitrogen‐containing molecule, as the CN precursor. Spectroscopic characterization and density functional theory calculations reveal that the prepared material exhibits a new molecular structure, which comprises two tetrazines and one triazine rings in the unit cell and is thermodynamically stable. The resultant carbon nitride shows an outstanding surface area of 130.4 m2 g−1 and demonstrates excellent CO2 adsorption per unit surface area of 47.54 μmol m−2, which is due to the existence of abundant free NH2 groups, basic sites and microporosity. The material also exhibits highly selective sensing over water molecules (151.1 mmol g−1) and aliphatic hydrocarbons due to its unique microporous structure with a high amount of hydrophilic nitrogen moieties and recognizing ability towards small molecules. [ABSTRACT FROM AUTHOR]

Mesoporous carbon nitrides with C3N5 and C3N6 stoichiometries created a new momentum in the field of organic metal‐free semiconductors owing to their unique band structures and high basicity. Here, we report on the preparation of a novel graphitic microporous carbon nitride with a tetrazine based chemical structure and the composition of C3N5.4 using ultra‐stable Y zeolite as the template and aminoguanidine hydrochloride, a high nitrogen‐containing molecule, as the CN precursor. Spectroscopic characterization and density functional theory calculations reveal that the prepared material exhibits a new molecular structure, which comprises two tetrazines and one triazine rings in the unit cell and is thermodynamically stable. The resultant carbon nitride shows an outstanding surface area of 130.4 m2 g−1 and demonstrates excellent CO2 adsorption per unit surface area of 47.54 μmol m−2, which is due to the existence of abundant free NH2 groups, basic sites and microporosity. The material also exhibits highly selective sensing over water molecules (151.1 mmol g−1) and aliphatic hydrocarbons due to its unique microporous structure with a high amount of hydrophilic nitrogen moieties and recognizing ability towards small molecules. [ABSTRACT FROM AUTHOR]

Effective learning has many and different disciplines, one of them is the improvement of students' soft skills which include different abilities, such as presentation, communicating, teamwork, time/project management and effective writing. This paper addresses the improvement of writing skills, particularly when writing a technical laboratory or mini-project report is used. The report should contain all the factors that enhance students' writing using the appropriate language and conventions. Here, we investigate the students' performance and response when applying the proposed guidelines and recommendations for the suggested structure of mini-projects or laboratory reports. The analysis contains a discussion of a case study conducted over 12 consecutive terms to assess student performance in four different courses using the proposed report structure. Moreover, it includes a discussion about the students' response for the questionnaire which explores students' satisfaction with the assigned lab tasks and proposed structure for five consecutive terms for a specific course, namely electrical machines. [ABSTRACT FROM AUTHOR]

We report on the preparation of ordered mesoporous carbon nitrides (MCN) with a 3D porous structure, tuneable nitrogen contents and basicity and their basic catalytic activities on the Knoevenagel condensation of benzaldehyde with malononitrile. The chemical structure and the nitrogen contents of the materials are finely tuned with the simple adjustment of the calcination temperature from 350 to 550 °C. The samples prepared at 350 and 400 °C exhibit C3N5 structures with 1‐amino/imino‐1,2,4‐triazole moieties, whereas the samples synthesised at 450, 500, and 550 °C possess C3N4 structures with 2‐amino/imino‐1,3,5‐triazine moieties. The materials prepared at the temperature lower than 400 °C show much higher activity than those of the samples prepared at 450, 500 and 550 °C. The change in the catalytic activities of these materials is linked with the change of the structure, nitrogen contents and the functional groups on the surface of the materials prepared at different temperatures. CO2 temperature programme desorption study reveals that 1‐amino/imino‐1,2,4‐triazole moieties in C3N5 samples provide high basicity due to the strain in 5‐membered 1,2,4‐triazole rings; however, the samples with 1,3,5‐triazine moieties have limited basicity which significantly affects the catalytic activity of the material. The optimised C3N5 catalyst shows an enhanced catalytic activity when compared to other mesoporous basic catalysts and C3N4. It is also found that the optimised catalysts are highly stable and can be recycled several times and no major change in the activity is observed. [ABSTRACT FROM AUTHOR]

Nanoporous carbon materials have been widely utilized for myriad applications owing to their intriguing physicochemical properties. Development of green and clean synthetic techniques/procedures to generate nanoporous carbon materials especially derived from inexpensive waste precursors/resources has rejuvenated the chemistry of carbon materials owing to the abundant nature and low cost of these sources and their ability to generate unique surface/porous structures. These nanoporous carbon materials have been heavily explored in multiple sectors such as soil/water remediation, adsorption and separation, catalysis, energy storage/conversion, capture and conversion of carbon dioxide. In this topical review, the recent state‐of‐the‐art research progress achieved in the design and development of waste‐derived advanced functionalized porous carbon materials are summarized. The various lab‐specific approaches and methodologies involved in synthesizing these materials are discussed in detail. In addition, the potential applications of waste‐derived functionalized porous carbons in the fields of environment, energy storage, and conversion applications are highlighted. Finally, a discussion on a few suggestions for future research is concluded. It is believed that this review provide inspiration for many new research activities over a wide range of disciplines. [ABSTRACT FROM AUTHOR]

The extensive use of petroleum-based synthetic and non-biodegradable materials for packaging applications has caused severe environmental damage. The rising demand for sustainable packaging materials has encouraged scientists to explore abundant unconventional materials. For instance, cellulose, extracted from lignocellulosic biomass, has gained attention owing to its ecological and biodegradable nature. This article reviews the extraction of cellulose nanoparticles from conventional and non-conventional lignocellulosic biomass, and the preparation of cellulosic nanocomposites for food packaging. Cellulosic nanocomposites exhibit exceptional mechanical, biodegradation, optical and barrier properties, which are attributed to the nanoscale structure and the high specific surface area, of 533 m2 g−1, of cellulose. The mechanical properties of composites improve with the content of cellulose nanoparticles, yet an excessive amount induces agglomeration and, in turn, poor mechanical properties. Addition of cellulose nanoparticles increases tensile properties by about 42%. Barrier properties of the composites are reinforced by cellulose nanoparticles; for instance, the water vapor permeability decreased by 28% in the presence of 5 wt% cellulose nanoparticles. Moreover, 1 wt% addition of filler decreased the oxygen transmission rate by 21%. We also discuss the eco-design process, designing principles and challenges. [ABSTRACT FROM AUTHOR]

Supercapacitors are increasingly used for energy conversion and storage systems in sustainable nanotechnologies. Graphite is a conventional electrode utilized in Li-ion-based batteries, yet its specific capacitance of 372 mA h g−1 is not adequate for supercapacitor applications. Interest in supercapacitors is due to their high-energy capacity, storage for a shorter period and longer lifetime. This review compares the following materials used to fabricate supercapacitors: spinel ferrites, e.g., MFe2O4, MMoO4 and MCo2O4 where M denotes a transition metal ion; perovskite oxides; transition metals sulfides; carbon materials; and conducting polymers. The application window of perovskite can be controlled by cations in sublattice sites. Cations increase the specific capacitance because cations possess large orbital valence electrons which grow the oxygen vacancies. Electrodes made of transition metal sulfides, e.g., ZnCo2S4, display a high specific capacitance of 1269 F g−1, which is four times higher than those of transition metals oxides, e.g., Zn–Co ferrite, of 296 F g−1. This is explained by the low charge-transfer resistance and the high ion diffusion rate of transition metals sulfides. Composites made of magnetic oxides or transition metal sulfides with conducting polymers or carbon materials have the highest capacitance activity and cyclic stability. This is attributed to oxygen and sulfur active sites which foster electrolyte penetration during cycling, and, in turn, create new active sites. [ABSTRACT FROM AUTHOR]

Multi-objective differential evolution (MODE) algorithm has been widely used in solving multi-objective optimization problems. In this paper, a hybridization technique is proposed to improve the performance of MODE algorithm in terms of speed and convergence. The proposed hybrid MODE-dynamic-random local search (HMODE-DLS) algorithm combines MODE and dynamic-random local search (DLS) algorithm. To evaluate the proposed algorithm and validate its performance, benchmark test problems (both constrained and non-constrained) are considered to be solved using MODE and the proposed HMODE-DLS algorithms. To compare between the two algorithms, five performance metrices are calculated, which are convergence, spread, generational distance, spacing and hypervolume ratio. Mean and standard deviation values for the performance metrics are reported, and the best in each category is highlighted. The Conv metric results of the new hybrid MODE are compared with other reported ones. Additionally, the effect of local search probability is studied for selected problems. In general, HMODE-DLS performance outshines, in terms of convergence and robustness, compared with other tested algorithms. HMODE-DLS is, generally, faster, and its results are of improved quality compared to MODE algorithm. [ABSTRACT FROM AUTHOR]

Summary: We demonstrate a simple template‐free green method to prepare copper oxide (CuO) nanoporous material using copper acetate as a single precursor with Piper nigrum (Indian black pepper) dried fruit extract as a reducing medium under microwave irradiation. The surface properties and morphology of the obtained CuO material were assessed using powder X‐ray diffractometer, X‐ray photoelectron spectrometer, field‐emission scanning electron microscope with elemental mapping analysis, focused ion beam high‐resolution transmission electron microscope, and N2 adsorption‐isotherm techniques. The characterization results reveal that the prepared CuO is a single monoclinic crystalline phase, and nanoporous in morphology with a specific surface area of 81.23 m2 g−1 and containing pore sizes between 3–8 nm. Nanoporous CuO showed excellent electrochemical energy storage performance with the specific capacitance of 238 Fg−1 at 5 mVs−1 when compared with commercially available CuO (75 Fg−1). Also, nanoporous CuO showed efficient desalting performance in the capacitive deionization system. This eco‐friendly synthesis derived nanoporous CuO can be applied as high‐performance supercapacitor material for high‐energy storage devices and desalination processes. [ABSTRACT FROM AUTHOR]

Organo‐functionalized materials with porous structure offer unique adsorption, catalytic and sensing properties. These unique properties make them available for various applications, including catalysis, CO2 capture and utilization, and drug delivery. The properties and the performance of these unique materials can be altered with suitable modifications on their surface. In this review, we summarize the recent advances in the preparation and applications of organo‐functionalized porous materials with different structures. Initially, a brief historical overview of functionalized porous materials is presented, and the subsequent sections discuss the recent developments and applications of various functional porous materials. In particular, the focus is given on the various methods used for the preparation of organo‐functionalized materials and their important roles in the heterogenization of homogeneous catalysts. A special emphasis is also given on the applications of these functionalized porous materials for catalysis, CO2 capture and drug delivery. [ABSTRACT FROM AUTHOR]

Environmental concerns due to excessive use of synthetic or petroleum-based materials have encouraged scientists to develop novel, sustainable, and multifunctional material using abundant lignocellulosic biomass. In this work, a study was conducted on the isolation of cellulose from wheat straw using two different methods: acidified sodium chlorite and alkaline hydrogen peroxide. A comparative study was carried out based on the yield and properties of extracted cellulose. The final product (after treatments) was characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA) for the identification of properties. Both the treatments isolated pure white color cellulose. However, the yield of cellulose isolated through acidified sodium chlorite treatment (81.4%) was higher than alkaline hydrogen peroxide treatment (79%). Moreover, no huge difference was observed in the crystallinity and thermal properties of extracted cellulose. [ABSTRACT FROM AUTHOR]

Environmental concerns due to excessive use of synthetic or petroleum-based materials have encouraged scientists to develop novel, sustainable, and multifunctional material using abundant lignocellulosic biomass. In this work, a study was conducted on the isolation of cellulose from wheat straw using two different methods: acidified sodium chlorite and alkaline hydrogen peroxide. A comparative study was carried out based on the yield and properties of extracted cellulose. The final product (after treatments) was characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA) for the identification of properties. Both the treatments isolated pure white color cellulose. However, the yield of cellulose isolated through acidified sodium chlorite treatment (81.4%) was higher than alkaline hydrogen peroxide treatment (79%). Moreover, no huge difference was observed in the crystallinity and thermal properties of extracted cellulose. [ABSTRACT FROM AUTHOR]

Environmental concerns due to excessive use of synthetic or petroleum-based materials have encouraged scientists to develop novel, sustainable, and multifunctional material using abundant lignocellulosic biomass. In this work, a study was conducted on the isolation of cellulose from wheat straw using two different methods: acidified sodium chlorite and alkaline hydrogen peroxide. A comparative study was carried out based on the yield and properties of extracted cellulose. The final product (after treatments) was characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA) for the identification of properties. Both the treatments isolated pure white color cellulose. However, the yield of cellulose isolated through acidified sodium chlorite treatment (81.4%) was higher than alkaline hydrogen peroxide treatment (79%). Moreover, no huge difference was observed in the crystallinity and thermal properties of extracted cellulose. [ABSTRACT FROM AUTHOR]

Synthesis of a highly ordered mesoporous acid- as well as metal-functionalized carbon (–SO3H/C–Si–Zr) material is achieved for the first time from a simple single-pot template-free carbonization of low-value bio-derived glycerol. Addition of TEOS to glycerol right before the carbonization was observed to facilitate molecular-level interactions between them to establish C–Si bonding, which eventually leads to the formation of a high surface area mesoporous –SO3H/C–Si composite material. Unlike this, the addition of ZrO(NO3)2·xH2O to glycerol could not have such an effect, but when Zr is used in the presence of TEOS the mixture could successfully produce the –SO3H/C–Si–Zr composite possessing mesoporosity and uniform acidity suitable for bulky tri-acetin production useful for fuel applications. Here TEOS is observed to play two roles, (1) as a surface area and porosity improver of graphitic carbon by its C–Si interaction and (2) as a mediator to involve Zr in the carbon composite structure through its Si–OH group. Thus, the combined inclusion of Zr and Si sources in the glycerol-derived carbon structure could successfully introduce the positive aspects of porosity improvement (by Si) and acidity improvement (by zirconia) in the mixed composite –SO3H/C–Si–Zr to produce the highest ever selectivity of tri-acetin (∼94 wt%) from the same low-value bio-derived glycerol by an acetylation reaction. The sustainability of the process lies in the utilization of waste glycerol as a source of the carbon composite, which in turn catalyzes selective low-value glycerol conversion to industrially important fuel additives. [ABSTRACT FROM AUTHOR]

In the present study, we have synthesized a nano-adsorbent of carboxymethyl cellulose; carboxymethyl cellulose/graphitic-carbon nitride/zinc oxide (CMC/g-C3N4/ZnO) by sol–gel technique. It has been utilized for the adsorptional elimination of methyl violet (MV) from aqueous solution. Maximum surface area as determined from the BET analyses is 9.214 m2/g. XRD analysis confirmed the semi-crystalline nature of the nano-adsorbent. Presence of desired functionalities on the surface of nano-adsorbent, CMC/g-C3N4/ZnO offered maximum interactions with the MV molecules. Isotherm studies generalized the monolayer adsorption of MV molecules with maximum adsorption capacity of 96.43 mg/g. Solution pH affected the adsorption rate to large extent and maximum occurred at pH 8. Pseudo-second order model better explained the adsorption process that determines the chemical interactions between methyl violet and CMC/g-C3N4/ZnO. [ABSTRACT FROM AUTHOR]

Environmental concerns due to excessive use of synthetic or petroleum-based materials have encouraged scientists to develop novel, sustainable, and multifunctional material using abundant lignocellulosic biomass. In this work, a study was conducted on the isolation of cellulose from wheat straw using two different methods: acidified sodium chlorite and alkaline hydrogen peroxide. A comparative study was carried out based on the yield and properties of extracted cellulose. The final product (after treatments) was characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA) for the identification of properties. Both the treatments isolated pure white color cellulose. However, the yield of cellulose isolated through acidified sodium chlorite treatment (81.4%) was higher than alkaline hydrogen peroxide treatment (79%). Moreover, no huge difference was observed in the crystallinity and thermal properties of extracted cellulose. [ABSTRACT FROM AUTHOR]

Herein, value-added materials such as activated carbon and carbon nanotubes were synthesized from low-value Miscanthus × giganteus lignocellulosic biomass. A significant drawback of using Miscanthus in an energy application is the melting during the combustion due to its high alkali silicate content. An application of an alternative approach was proposed herein for synthesis of activated carbon from Miscanthus × giganteus, where the produced activated carbon possessed a high surface area and pore volume of 0.92 cm3.g−1 after two activation steps using phosphoric acid and potassium hydroxide. The SBET of the raw biomass, after first activation and second activation methods showed 17, 1142 and 1368 m2.g−1, respectively. Transforming this otherwise waste material into a useful product where its material properties can be utilized is an example of promoting the circular economy by valorising waste lignocellulosic biomass to widely sought-after high surface area activated carbon and subsequently, unconventional multi-walled carbon nanotubes. This was achieved when the activated carbon produced was mixed with nitrogen-based material and iron precursor, where it produced hydrophilic multi-wall carbon nanotubes with a contact angle of θ = 9.88°, compared to the raw biomass. synthesised materials were tested in heavy metal removal tests using a lead solution, where the maximum lead absorption was observed for sample AC-K, with a 90% removal capacity after the first hour of testing. The synthesis of these up-cycled materials can have potential opportunities in the areas of wastewater treatment or other activated carbon/carbon nanotube end uses with a rapid cycle time. [ABSTRACT FROM AUTHOR]

BACKGROUND: Brewer's Spent Grain (BSG), a form of lignocellulosic biomass more commonly known as barley waste was used to synthesize activated carbon (AC) and carbon nanotubes (CNTs). The produced materials were used in water remediation application. RESULTS: A novel approach involving two activation steps; first, with phosphoric acid (designated BAC‐P) and then using potassium hydroxide (designated BAC‐K) was proposed for the production of AC and CNTs from BSG. The AC produced showed a surface area as high as 692.3 m2 g−1 with a pore volume of 0.44 cm3 g−1. This can help aid and facilitate the circular economy by effectively upcycling and valorizing waste lignocellulosic biomass to high surface area AC and subsequently, multi‐walled carbon nanotubes (MWCNTs). Consequently, MWCNTs were prepared from the produced AC by mixing it with the nitrogen (N)‐based material melamine and iron precursor, iron (III) oxalate hexahydrate, where it produced hydrophilic MWCNTs. Both AC and CNT materials were used in heavy metal removal (HMR), where the maximum lead absorption was observed for sample BAC‐K with 77% removal capacity after the first hour of testing. CONCLUSION: This result signifies that the synthesis of these upcycled materials can have an application in the areas of wastewater treatment or other AC/CNT end uses with a rapid cycle time. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Herein, activated carbon (AC) and carbon nanotubes (CNTs) were synthesised from potato peel waste (PPW). Different ACs were synthesised via two activation steps: firstly, with phosphoric acid (designated PP) and then using potassium hydroxide (designated PK). The AC produced after the two activation steps showed a surface area as high as 833 m2 g−1 with a pore volume of 0.44 cm3 g−1, where the raw material of PPW showed a surface area < 4 m2 g−1. This can help aid and facilitate the concept of the circular economy by effectively up-cycling and valorising waste lignocellulosic biomass such as potato peel waste to high surface area AC and subsequently, multi-walled carbon nanotubes (MWCNTs). Consequently, MWCNTs were prepared from the produced AC by mixing it with the nitrogen-based material melamine and iron precursor, iron (III) oxalate hexahydrate. This produced hydrophilic multi-wall carbon nanotubes (MWCNTs) with a water contact angle of θ = 14.97 °. Both AC and CNT materials were used in heavy metal removal (HMR) where the maximum lead absorption was observed for sample PK with a 84% removal capacity after the first hour of testing. This result signifies that the synthesis of these up-cycled materials can have applications in areas such as wastewater treatment or other conventional AC/CNT end uses with a rapid cycle time in a two-fold approach to improve the eco-friendly synthesis of such value-added products and the circular economy from a significant waste stream, i.e., PPW. [ABSTRACT FROM AUTHOR]

Due to increasing concerns about global warming and dwindling oil supplies, the world’s attention is turning to green processes that use sustainable and environmentally friendly feedstock to produce renewable energy such as biofuels. Among them, biodiesel, which is made from nontoxic, biodegradable, renewable sources such as refined and used vegetable oils and animal fats, is a renewable substitute fuel for petroleum diesel fuel. Biodiesel is produced by transesterification in which oil or fat is reacted with short chain alcohol in the presence of a catalyst. The process of transesterification is affected by the mode of reaction, molar ratio of alcohol to oil, type of alcohol, nature and amount of catalysts, reaction time, and temperature. Various studies have been carried out using different oils as the raw material; different alcohols (methanol, ethanol, butanol); different catalysts; notably homogeneous catalysts such as sodium hydroxide, potassium hydroxide, sulfuric acid, and supercritical fluids; or, in some cases, enzymes such as lipases. This article focuses on the application of heterogeneous catalysts for biodiesel production because of their environmental and economic advantages. This review contains a detailed discussion on the advantages and feasibility of catalysts for biodiesel production, which are both environmentally and economically viable as compared to conventional homogeneous catalysts. The classification of catalysts into different categories based on a catalyst’s activity, feasibility, and lifetime is also briefly discussed. Furthermore, recommendations have been made for the most suitable catalyst (bifunctional catalyst) for low-cost oils to valuable biodiesel and the challenges faced by the biodiesel industry with some possible solutions. [ABSTRACT FROM AUTHOR]

The usage of agricultural waste-based bio-adsorbents for the removal of environmental pollutants from water is gaining extensive attention. In this paper, carrot residue (CR) ( Daucus carota L.) was used for the production of activated carbon (AC) via chemical activation with HNO3. CR derived activated carbon (CAC) was characterized by various analytical techniques. The Brunauer-Emmett-Teller surface area was found to be 17.76 m2 g−1. The efficacy of this AC in adsorbing BrO3− from water samples was studied at time, pH, temperature, and initial BrO3− concentrations by batch studies. The concentration of BrO3− was assessed by ultra-performance liquid chromatography-mass tandem spectrometry. A maximum adsorption capacity of 16.66 mg g−1 at 298 K was obtained from the Langmuir isotherms fit. The kinetic data followed closely the pseudo-first-order rate kinetic model. The thermodynamic study of BrO3− adsorption data showed that the adsorption was feasible, spontaneous, and endothermic in nature. The practical efficacy of CAC was performed for BrO3− removal from tap water as well as bottled water samples. [ABSTRACT FROM AUTHOR]

This study aimed at improving the productivity of a falling film solar desalination unit by cooling the glass cover and by improving the hot surface wettability. The glass cover was made of double layers through which cooling water passes. The advantage of this design is that the latent heat of evaporation is absorbed by the cooling water and returned to the system. The effect of the various parameters such as feed water flow rate, cooling water flow rate, weather conditions, solar irradiation intensity, and collector’s surface area was investigated. The results showed that increasing the cooling water flow rate enhanced fresh water production. The productivity of the unit decreased with increasing feed water flow rate. Recycling the hot water to the feed water tank improved the productivity of the unit from 0.13 to 0.18 L/h (~34%). Fog formation on the double glass cover was found to reduce the productivity of the unit. Modifying the surface of the black plate with cotton cloth or with plastic strips improved the productivity by 50% (0.13–0.19 L/h). [ABSTRACT FROM PUBLISHER]