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The escalating accumulation of textile waste in landfill sites poses a significant environmental hazard that requires immediate intervention. This study focused on the sustainable and value-enhancing management of used fabrics via chemical recycling. The acid hydrolysis of six distinct types of cotton-based fabric waste (FW) has been conducted for the first time using a milder concentration (10%) of acid. The experiments resulted in the successful extraction of microcrystalline cellulose (MCC). The product underwent various analytical techniques, such as XRD, FTIR, FESEM, TGA, DTG, and PL spectroscopy, to verify the presence of microcrystalline cellulose (I-cellulose). The various sources of cellulose yielded varying results for MCC in terms of the yield (ranging from 28.2% to 80.2%), crystallinity index (ranging from 83.9% to 87%), crystallite size (ranging from 5.287 to 5.952 nm), thermal stability (ranging from 310 °C to 327 °C), and heat of fusion (ranging from 302 to 364 J g−1). The physico-chemical parameters of these six MCC samples were similar, with the carbon content ranging from 38.7% to 47%. The samples exhibited a range of bulk density values between 0.077 and 0.1975 g cc−1, and a water retention value (WRV) between 91.3% and 95.5%. The efficient retrieval of cellulose from various fabric waste sources offers an eco-friendly and sustainable approach to bolster waste management initiatives for fabric-related refuse. [ABSTRACT FROM AUTHOR]

Food grade dyes pose severe health hazards when consumed in excessive amounts or enter body via contaminated water. Despite its harmful effects, Allura Red (AR) is very less explored dye for its removal, especially using agricultural/fruit waste. This study presents efficient removal of an important and unsafe food grade dye, AR via adsorption. Waste watermelon peel waste has been used for the first time for treatmenting wastewater contaminated with AR. Waste was converted to two types of adsorbents, with and without subjecting it to pyrolysis. Both the adsorbents were characterized for functionality and crystallinity and used for conducting adsorption studies. Removal of dye was evaluated by intrinsic strategy of monitoring the model solutions under pre‐ and post‐adsorption conditions. Removal percentage of dye was determined by calculating its initial (Co) and final (Cf) concentrations in solution using the formula (see Eq. (1)). Various reaction parameters important for adsorption, viz. pH, adsorbent dose, residence time, reaction temperature and particle size were optimized. Results indicate that ~80 % and >92 % dye could be removed using 0.5 g/L adsorbent before and after pyrolysis respectively in 3.5 h from its 2 ppm concentration in modelled water. [ABSTRACT FROM AUTHOR]

The inadvertent release of crude oil and its derivatives into aquatic ecosystems has emerged as a significant and concerning environmental issue, often leading to catastrophic accidents. Ongoing research efforts are diligently working toward devising effective remedies to curtail and alleviate the adverse impacts of these incidents on the delicate balance of aquatic life. Amidst these endeavors, cellulose, an eco-friendly and cost-effective material, has garnered attention for its potential in addressing this formidable challenge. In this pioneering study, we delve into a novel approach by harnessing waste-derived cellulose to combat oil spills within aquatic environments. Specifically, cellulose was extracted from post-consumer waste cloths (PCWCs) and subjected to a transformative treatment involving strategically chosen silanating agents. This treatment facilitated the creation of a three-dimensional, water-repelling matrix, characterized by a remarkable hydrophobic nature, exemplified by a substantial contact angle of 126.2°. The resultant matrix exhibited exceptional reusability, demonstrating consistent performance over five successive cycles, and showcased an impressive oil absorption capacity of up to 24.36 g/g. Notably, the engineered polyester sponge exhibited a remarkable buoyancy, being approximately 28.5 times lighter than water, and boasted a density ranging from 0.026 to 0.040 g/cm3. This innovative approach not only presents a tangible solution for oil–water separation during scenarios of marine or environmental oil spills, but it also offers a sustainable and valuable application for well-processed PCWCs. By effectively harnessing the intrinsic properties of cellulose and employing meticulous design, this study represents a significant stride toward mitigating the ecological impact of accidental oil discharges in aquatic ecosystems. [ABSTRACT FROM AUTHOR]

Starch-based biopolymers occupy a significant place in polymer world for replacing plastics derived from petrochemicals. Their non-toxicity, bio-compatible nature and comparable mechanical and degradation properties make them suitable candidates for various applications, including packaging sector. Starch derived from a variety of agricultural waste is converted to bio-composites by chemical modification in the presence of plasticisers and other chemical moieties. These bio-polymers are biodegradable in nature; however, they are associated with certain disadvantages, such as brittleness, moisture sensitivity, and poor thermal and mechanical properties. Efforts are being made by researchers to overcome these challenges by various strategies in order to make it at par to the conventional plastic. Few companies have initiated using starch-based biopolymers for producing commercial products, but scientific world definitely demands significant studies that can enhance the properties of this material to an appreciable extent. This will also help in reducing the production cost and improving the overall economy of biopolymers' segment. [ABSTRACT FROM AUTHOR]

Massive amounts of unmanaged agricultural waste have drawn attention to the utilization of biomass for the production of prospective chemicals and polymeric materials, as well as their frequent application for generating various forms of energy. Furan dicarboxylic acid (FDCA) has come up as an important platform chemical derived from the lignocellulosic agricultural waste, which can be converted into various products. Polyethylene furan-2, 5-dicarboxylate (PEF), and aligned compounds obtained from FDCA are potential environmentally benign polyesters. These polyesters can efficiently substitute conventionally established polymers, such as polyethylene terephthalate (PET), for different applications. Efforts are required to optimize the properties of PEF, which can be helpful in its commercialization providing it a suitable place for daily life applications. [ABSTRACT FROM AUTHOR]

The COVID-19 Pandemic have caused severe impact on lives in various ways, but our environment has experienced a positive outcome due to the lockdown which was imposed all over world including Himalayan region of India. The worldwide spread of COVID 19 has reduced movement of vehicles, industries and all tourism activities. Due to shutdown of all the commercial activities and traffic has helped the environment to reclaim naturally. The Himalayas is one of the world's most fragile and sensitive hotspots to global climate change, with impacts manifesting at a particularly rapid rate. The Himalayan glaciers are the water towers of Asia, and the source of many of the world's great rivers. In this research paper, an attempt has been made to describe the improvement in physiochemical characteristics of surface water, all parameters were compared with BIS standard of drinking water quality during pre lockdown and lockdown period. The ambient air quality have also been significantly improved and noise level were also found under permissible limit of Ambient air quality Standard. [ABSTRACT FROM AUTHOR]

Owing to the scarcity of raw materials and environmental concerns, concrete industry demands a suitable environment friendly material, which can substitute it partially while maintaining its required characteristics. Biochar from agricultural biomass is sustainable product for construction uses without any adverse effect on environment. It acts as effective binder/filler for enhancing performance of construction material, including mechanical/rheological properties, water absorbing capacity, insulating nature, chemical stability and environmental safety. This review presents significant aspects of biochar as additive to cementitious materials. It highlights its role in improving the performance of concrete for various applications in construction industry. It also suggests that a suitable permutation and combination is necessary for optimizing its properties and effectiveness. It can be derived from the studies carried out in this domain that on average, 1–3% addition of biochar derived from various lignocellulosic biomass can serve as optimum concentration for enhancing performance in building constituents. The review also highlights the economic viability and environmental benefits of biochar addition in cementitious composition. This article will provide deep insight and understanding about appropriateness of biochar as important constituent in construction industry. It will be encouraging for the researchers to strengthen their observations and outcomes, helping in categorizing biochar as 'green concrete' in upcoming time. Biochar is an efficient binder for cement to be used for costruction/buildings. Advantages offered by it to buildings include mainly improved rheology, chemical stability, water retention ability and protection from cracks. It helps in maintaining indoor temperature of builidngs. It is an economically feasible additive for construction purpose and reduces environmental pollution by sequestring CO2. Being able to be produced from agricultural wastes, it acts as a measure to waste management also. [ABSTRACT FROM AUTHOR]

Anaerobic digestion (AD), one of the most promising routes for producing clean energy from biodegradable wastes, encounters difficulties at operational and mechanistic levels impacting its overall efficiency. Along with other solutions to overcome this problem, biochar has arrived as a worthwhile additive to enhance the performance of the process. This review aims to discuss various perspectives of biochar addition to an anaerobic digester. It summarizes the mechanism of biochar action during AD. A direct inter-species electron transfer offers a synergistic mechanism specifying different aspects of biogas production. The importance of characteristics of biochar (ion-exchange capacity, surface properties, electrical conductivity, and hydrophobicity) has been explained in enhancing AD performance. Studies indicate that a surface area >150 m2/g and a particle size <1 cm can be referred to as benchmark along with its supporting properties apt for AD. Researchers have recommended varying amounts of biochar (up to 15 g/l) for optimizing biogas production. The applicability of biochar for upgrading the biogas with respect to significant impurities (CO2, H2S, and NH3) has been discussed in detail. Along with the beneficial effects of biochar, its limitations in AD have also been identified, which need to be addressed wisely in order to optimize the process and make an unbiased shift toward validating the candidature of biochar in AD. The whole discussion indicates that consciously planned scheme utilizing biochar may be helpful in enhancing the effectiveness of AD for biogas generation, which may prove to be an impactful technology in the world of renewable energy. [ABSTRACT FROM AUTHOR]

In the present work, waste clothes (cotton:polyester ~ 19:1) have been employed as an unconventional resource for the generation of cellulose, establishing a proof-of-concept for its value-added conversion to useful products. The strategy adapted for chemical recycling of waste cloth to cellulose involved manual sorting of non-biodegradable material from waste followed by acidic hydrolysis and bleaching. As a result of the experiments, up to 80.4% microcrystalline cellulose (MCC) was recovered during the procedure under optimum reaction conditions (8% H2SO4, bath ratio 1:25, 95 °C, 30 min followed by 10 min grinding time). Results demonstrated that MCC extracted by this route was crystalline (crystallinity index 58%) with appreciable water holding capacity (21% w/w) and thermally stable up to ~ 350 °C. It contained chemically active groups at the surface, which can help to utilize it for various applications on a sustainable basis. The whiteness index of the FESEM images as estimated by the MATLAB image processing tool was 81.27. [ABSTRACT FROM AUTHOR]

Vitrimeric materials have emerged as fascinating and sustainable materials owing to their malleability, reprocessability, and recyclability. Sustainable vitrimeric materials can be prepared by reinforcing polymeric matrix with bioderived fillers. In the current work, a sustainable vitrimer is prepared by incorporating biomass-derived activated carbon (AC) filler into the epoxy matrix to achieve enhanced thermal and mechanical properties. Thus, prepared biocomposite vitrimers demonstrate a lower-temperature self-healing (70°C for 5 min) via disulfide exchanges, compared to the pristine epoxy vitrimers (80°C for 5 min). Significantly, the self-healing performances have been studied extensively with the flexural studies; and changes in material healing efficiency have been demonstrated based on the observed changes in modulus. [ABSTRACT FROM AUTHOR]

Polymer nanocomposites offer enhancement in thermomechanical and physicochemical properties of polymers with the presence of a little amount of nanostructured fillers such as carbon nanotubes, graphene, and layered silicates. A facile and rapid preparation of hytrel (HTL)-graphene oxide (GO) nanocomposites is done via a solution mixing method. The influence of GO content (0.1, 0.5, 1, 2, and 5 wt%) on mechanical and thermal properties of GO/HTL nanocomposites has been evaluated by using various techniques such as tensile testing, thermogravimetric analysis, differential scanning calorimetry, and dynamic mechanical analysis. The thermal stability and mechanical properties of GO/HTL nanocomposites were increased with increasing GO content. The composites have valuable improvement in tensile strength (139%) and storage modulus (72%) for HTL composite containing 5 wt% GO. The incorporation of GO into HTL polymer shows enhancement in thermal and mechanical properties due to the presence of strongest noncovalent interaction (π–π stacking) between the interface of nanocomposites. These enhanced physical properties of GO/HTL composites show its potential use in structural application. [ABSTRACT FROM AUTHOR]

In the present manuscript, the effect of the synthetic route on the properties of SiO2-ZrO2 has been evaluated. Co-precipitation, sol-gel and microwave methods were adopted for synthesizing the structured oxide. The properties of the final products such as surface morphology, crystallinity, surface area, pore volume and size, particle size and total acidity were examined using standard instrumentation like Fe-SEM, XRD, BET and TPD. The results revealed that the mixed oxides were mesoporous in nature with a high BET surface area (315-435m²/g). Among various methods, the microwave route achieved the highest surface area (433m²/g), pore volume (0.70cc/g) and pore size (6.50nm). The total acidity of the sample synthesized by the microwave reactor was also higher (0.296mmol/g) than that resulting from other methods. Results conclude that microwave method is a suitable choice for synthesizing the structured oxides with desirable properties. [ABSTRACT FROM AUTHOR]

Sulfated zirconia is a very strong solid acid catalyst which can be utilized for various reactions. The present study focuses on synthesis of zirconia-based catalyst with high acidity and high surface area, particularly for isomerization reaction. Sulfated zirconia has been obtained by sulfation of zirconia prepared by hydrothermal route. The catalyst was developed by impregnating tungstophosphoric acid on sulfated zirconia by wet incipient method. The catalyst was characterized through Brunauer–Emmett–Teller (BET) surface area, temperature-programmed desorption of ammonia, temperature program reduction of hydrogen, Fourier transmission infrared spectroscopy, and thermogravimetric analysis. The results revealed that the catalyst is crystalline in nature with surface area 190–225 m2 g−1 and acidity 0.135–0.558 mmol g−1. Twenty-five percent conversion was obtained (as confirmed by gas chromatography) at 225°C using n-hexane as model hydrocarbon in fixed-bed microreactor. [ABSTRACT FROM AUTHOR]

Increasing consumption of fossil fuels and environmental concern has led to increased use of compressed natural gas (CNG) in the transportation sector. Keeping in view limited resources of CNG, biogas is advised as potential fuel to provide continuous supply of CNG in the form of bio-CNG. Various technologies, that is, physical and chemical absorption (using water and amine solutions, respectively, for the absorption of carbon dioxide), pressure swing adsorption, membrane separation, and cryogenic separation, are available for purifying biogas and thus upgrading it, to bio-CNG with about 95% methane. Among these, water scrubbing and pressure swing adsorption are the best technologies with respect to various aspects including cost; however, suitability of a technology is decided by various factors including size/quantity of biogas generation, targeted quality of biogas, site of application, and economics of process. Copyright © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The present work focuses on the bio-methane production potential of jatropha defatted waste (JDFW) in batch type continuous stirred tank reactor (CSTR). JDFW was codigested with cow dung (CD) as inoculum in various ratios. 75:25 ratio of JDFW and CD with carbon to nitrogen (C/N) ratio 12:1 was chosen as the optimum to run in CSTR. 65-69% methane was obtained in 0.184m3 of biogas per kg of total solid in only 15 days. The efficient energy gain and reduction in hydraulic retention time (HRT) of bio-methane production process was successfully accomplished by minimizing the usage of fresh water and external nutrients. The integration of anaerobic digestion with CSTR could maintain the sustainability of biomethane production, and also significantly reduced the HRT of the process. © 2017 American Institute of Chemical Engineers Environ Prog, 36: 845-849, 2017 [ABSTRACT FROM AUTHOR]

Publisher's note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. The original article can be found online at https://doi.org/10.1007/s11356-023-26438-y. [Extracted from the article]

Increased use of biofuels from non‐renewable resources is required for sustainable development of the society. Biogas being almost pure methane, occupies importance to be used in place of compressed natural gas as transportation fuel in future. Lignocellulosic biomass (agricultural and forestry residues) are inexpensive and abundantly available source of energy. Pilot scale continuous stirred tank reactor was designed for jatropha de‐oiled cake (JDOC) with a total capacity of 40 m3. JDOC was digested with cow dung (3:1) in pilot scale reactor for continuous production of biogas for 120 days at 35°C. Around 20 m3 biogas was produced per day as a regular operation in only 5 days. © 2018 American Institute of Chemical Engineers Environ Prog, 38: 198–200, 2019 [ABSTRACT FROM AUTHOR]

In this study, five Chlorella species ( Chlorella vulgaris, Chlorella minutissima, Chlorella pyrenoidosa, Chlorella sp.1 and Chlorella sp.2) were grown in various nutrient medium including BG-11, BBM, Fog's medium and MN medium for the evolution of biomass and lipid production potential. Among the tested medium, BG-11 was found most economical and efficient medium for all Chlorella species. To see the impact of organic carbon sources on lipid production potential, all microalgae species were also cultured in selected medium (BG-11) with different organic carbon sources like glucose, glycerol, sodium acetate, and sucrose under mixotrophic condition. The results showed that all Chlorella species performs better under mixotrophic condition, but Chlorella vulgaris achieved maximum lipid productivity (3.5 folds higher) in glycerol supplemented culture medium than control medium among all species. [ABSTRACT FROM AUTHOR]

Lignocellulosic wastes, inexpensive and potential sources of bioenergy were explored for delignification and production of biogas. Wheat straw was subjected to chemical and biological treatment methods for removal of lignin, facilitating bio-methanation. Pretreatment produced remarkable results with an enhanced amount of methane. Bio-methanation of wheat straw after pretreatment produced biogas with an appreciable methane content (acid treatment 80%, alkaline treatment 74%, thermal treatment 77%, and fungal treatment 92%). Among all, fungal treatment responded to maximum delignification and biogas generation. The method has the potential to be converted to technology for large scale operations. [ABSTRACT FROM AUTHOR]

The adsorption of copper(II) on tea waste has been studied in batch mode using flame atomic absorption spectroscopy for metal estimation. Important process parameters like adsorbent dose, pH, contact time, reaction temperature, shaking speed and particle size were investigated. Adsorption was found to be in accordance with Freundlich and Langmuir isotherms. The maximum amount of copper(II) adsorbed (qm), as evaluated by Langmuir isotherm, was approximately 1.33 mg per gram of powder of tea waste per litre of solution. The optimized process parameters were observed to be 3 g adsorbent, pH 5, 40°C temperature, 120 rpm shaking speed and 150 μm particle size. The effectiveness of tea waste for copper removal from industrial effluent was observed to be around 95.345%. The used tea waste after adsorption produced 51.76% methane as biofuel. [ABSTRACT FROM AUTHOR]

A correction to the article "Influence of pretreatment processes onto bio-methanation of wheat straw" that was published in the 2015 issue is presented.