This study investigates two parallel routes for converting chicken feather waste into biosorbent materials designed for the adsorption of methyl orange (MO). Keratin was recovered by alkaline hydrolysis of chicken feathers (CF), while a separate feather fraction was chemically treated to obtain modified feathers (MF). The adsorption performance of the two materials was subsequently compared under identical experimental conditions. Structural, morphological, thermal, and surface properties were examined by FTIR, XRD, SEM–EDX, TGA/DTG, DSC, and pHpzc determination. Time-dependent kinetic data showed the best agreement with the pseudo-second-order model, with R² values of 0.997 for keratin and 0.998 for MF. Additional interpretation based on the intraparticle diffusion and Boyd models indicated that external film transport and intraparticle diffusion jointly controlled the overall adsorption rate. The equilibrium results were represented satisfactorily by the Langmuir equation, yielding R² values of 0.991 for keratin and 0.992 for MF. Under the selected conditions of pH 4, 100 min contact time, adsorbent masses of 0.10 g for keratin and 0.125 g for MF, at an operating temperature of 50 °C, the corresponding maximum adsorption capacities reached 34.6 ± 0.32 mg g⁻¹ and 21.55 ± 0.27 mg g⁻¹, respectively. The negative Gibbs free-energy values and positive enthalpy changes indicated a thermodynamically favorable and heat-assisted adsorption process. The magnitude of the thermodynamic parameters, together with the mechanistic analysis, suggests that physical interactions were predominant. Dual valorization of chicken feathers into sustainable biosorbents. Extracted keratin and modified feathers were comparatively evaluated. Both biosorbents effectively removed methyl orange from water. Adsorption was analyzed by kinetics, isotherms, and thermodynamics. Low-cost biosorbents show promise for sustainable wastewater treatment.
Pterospermum acerifolium (PA) was used in this study as the raw material for the production of extracted pulp. This plant is mainly used in antioxidants, analgesics and is also used in the paper industry to produce paper. The present study focus on production of Hydroxymethylfurfural (HMF) from the cellulose pulp extracted from PA using Kraft pulping and soda processes. The biomass sample was first pre-treated using both the processes to remove lignin, followed by bleaching. The cellulose pulp extracted was further characterized by XRD, FTIR and Total carbohydrate content. From the characteristic peaks, the presence of cellulosic components was confirmed. Finally, the extracted cellulose was tested for production of HMF using Zn/Sn modified HZSM-5 as a catalyst. The synergistic Lewis-Brønsted acid functionality of the Zn-Sn/HZSM-5 catalyst enhances glucose isomerization and dehydration, which leads to efficient conversion of lignocellulose into HMF with enhanced selectivity and biomass valorisation. The surface and structural morphology of bimetallic-zeolite catalyst was also studied using XRD and FESEM-EDS. The HMF produced in this process was analysed using High-Performance Liquid Chromatography (HPLC). HMF yield of 33.14
One of the most common organic pollutants found in waters is phenol, which is toxic to aquatic life and humans. The present study explored the feasibility of converting sugarcane bagasse into biochar adsorbent to efficiently remove phenol from river water. Chemically treated biochar (CTB) and grapheme-coated biochar (GCB) were produced from the pyrolysis of sugarcane bagasse at 300, 400, and 500 °C, followed by chemical activation with HCl and grapheme oxide treatment, respectively. The resulting materials were characterised using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy with energy-dispersive X-ray spectroscopy (FESEM), and Brunauer-Emmett-Teller surface area analysis (BET). To study the adsorption capacity of CTB and GCB for phenol removal under varying reaction conditions, batch adsorption experiments were performed. GCB, under optimal operating conditions, achieved a maximum phenol removal efficiency of 95.6
An integrated biorefinery process was developed to convert tobacco straw into valuable antimicrobial compounds and soluble fertilizers. Microwave assisted hydrothermal treatment was used to hydrolyze tobacco straw, and the non-detoxified hydrolysates obtained at 120 °C and 150 °C both supported the growth of beneficial microbe Bacillus amyloliquefaciens strain Cas02 without extra nutrition addition. The fermentation extracts were investigated for their inhibitory effect against plant pathogen indicators, only fermentation extracts from 120 °C hydrolysate showed inhibitory effect. This indicates that while the 150 °C hydrolysate permits cell growth, the lignocellulosic-derived inhibitors generated at higher hydrothermal temperatures (150–180 °C) negatively impact the strain’s secondary metabolism. Further, antimicrobial compounds were extracted by ethyl acetate and identified to be iturins and macrolatins. The active compounds rich extract after ethyl acetate extraction showed much stronger antifungal and antibacterial activities. Composition analysis revealed that residual ferments after antimicrobial compounds extraction were rich in carbohydrate and protein, and these extracts significantly improved the growth and salt resistance of peanut seedlings. All these indicated that tobacco straw can be valorized to produce valuable chemicals.
A potent protease-producing bacterium was isolated from environmental samples collected from a municipal waste treatment plant and dairy effluent site and screened on skim milk agar for extracellular protease production. Among approximately 30 isolates, 12 showed distinct proteolytic activity under solid-state fermentation (SSF) using wheat bran as substrate. Isolate VSP11 exhibited the highest proteolytic index (4.00) and maximum protease activity (103.2 U/gds) and was selected for further study. Morphological and molecular characterization based on 16 S rRNA gene sequencing identified the isolate as Bacillus subtilis strain VSP11. Protease production by B. subtilis VSP11 was enhanced under SSF employing wheat bran as a low-cost agro-residue substrate. Initially, one-factor-at-a-time (OFAT) optimization was performed to evaluate the influence of physicochemical parameters and nutritional supplements on enzyme production. Significant variables were subsequently screened using Plackett–Burman design, which identified water content, yeast extract, and peptone as the major factors affecting protease production. Further optimization using Central Composite Design under Response Surface Methodology (CCD-RSM) generated a statistically significant predictive model with an R² value of 0.906. The optimized conditions consisting of 20 mL water content, 0.5 g yeast extract, and 0.5 g peptone per 5 g wheat bran predicted a protease activity of 469.71 U/gds, while validation experiments yielded 468.73 U/gds. The close agreement between predicted and experimental values confirmed the reliability of the developed model. These findings demonstrate the potential of B. subtilis strain VSP11 for economical and sustainable protease production using agro-waste under SSF conditions.
Soluble yeast β-glucans are widely used in food, feed, pharmaceutical, and biotechnological applications. Their production commonly relies on acid hydrolysis or chemical derivatisation, processes that offer limited control, generate substantial chemical waste, and may compromise β-glucan functionality by introducing new functional groups on sugar moieties. In this work, we investigate an enzymatic approach for the controlled solubilisation of native, insoluble yeast β-glucan to lower-molecular-weight fragments. The impact of enzyme selection and processing parameters (pH, temperature, time) on solubilisation efficiency and molecular structure of the solubilised product was evaluated. Within 24 h, 9 to 95
Nighttime radiative cooling, a passive cooling technology, has immense potential for energy conservation and emission reduction. This study investigates the novel application of renewable diatoms to prepare a high-performance biochar tailored for nighttime radiative cooling. Under optimal conditions (heating rate of 12 °C/min, final temperature of 300 °C, and 0 h holding time), the diatom-based biochar (DB) achieved a significant temperature decrease of up to 20.4 °C in outdoor tests. It exhibited an average infrared emissivity of 94.35
The palm oil industry produces oil palm empty fruit bunch (OPEFB), which is one of the largest, most abundant lignocellulosic residues. The conversion of OPEFB to methane is however limited by the interplay of various operational variables. The study developed an integrated experimental, machine learning, eXplainable artificial intelligence (XAI) spatial analysis and evolutionary optimization framework to predict and maximize methane production from OPEFB. In a period from January to November 2025, four laboratory-scale anaerobic digestion experiments generated a total of 5,452 experimentally measured observations. The operational conditions investigated were temperature (30–55 °C), pH (6.0–8.0), organic loading rate (1–6 g VS L⁻¹ day⁻¹), hydraulic retention time (10–40 days), and C: N ratio (20–35). From these laboratory-scale anaerobic digestion experiments was produced methane yields ranging from 181.44 to 282.42 mL CH₄ g⁻¹ VS having a mean of 231.89 ± 15.22 mL CH₄ g⁻¹ VS. Five predictive models including Multiple Linear Regression (MLR), Artificial Neural Network (ANN), Random Forest (RF), Support Vector Regression (SVR) and Gradient Boosting Regression (GBR) were evaluated. The results showed that the MLR was the best model, with the predictive performance with R² = 0.5513, RMSE = 10.14 mL CH₄ g⁻¹ VS, MAE = 8.17 mL CH₄ g⁻¹ VS, and MAPE = 3.54
An increasing demand for sustainable protein sources has stimulated interest in converting lignocellulosic agro-industrial residues into single-cell protein (SCP). This research aimed to develop an optimized bioconversion process for producing SCP from wheat bran (WB) using indigenous bacterial isolates. Initially, bacterial isolates were screened for protein production, and the two best-performing isolates were identified as Pseudomonas guariconensis and Acinetobacter schindleri by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Different pretreatment strategies were comparatively evaluated, followed by optimization of the selected pretreatment using Response Surface Methodology based on Box-Behnken Design. The optimized conditions (1.9
Depleting fossil fuel reserves, rising energy demand, and increasing environmental concerns have accelerated the search for renewable and sustainable alternatives for fuels and chemicals. Lignocellulosic biomass (LB) is an abundant and renewable feedstock with significant potential for the production of bioethanol, biochemicals, and other value-added products. However, its efficient utilization is hindered by the recalcitrant structure of the lignocellulosic matrix, primarily due to intricate and complex interactions among cellulose, hemicellulose, and lignin coupled with high crystallinity of cellulose, which render its fractionation extremely challenging. Therefore, an effective pretreatment step is essential to disrupt the biomass structure and improve enzymatic accessibility to constituent polysaccharides. Among various pretreatment technologies, ionic liquid (IL)-based pretreatment has emerged as a promising approach owing to its ability to effectively deconstruct LB under ambient conditions with enhanced enzymatic saccharification, and reduced inhibitors formation. Recently, ILs are being investigated as promising, efficient and eco-benign LB pretreatment agents. This review provides a comprehensive overview of IL-based pretreatment of LB, including fundamental properties of ILs, their pretreatment mechanisms, factors influencing their performance, toxicity, recovery, recyclability, and recent advances in IL-integrated pretreatment strategies. Further, the review examines the production of biofuels and value-added bioproducts from IL-pretreated biomass, nanotechnology-based approaches for IL pretreatment, and the emerging role of machine learning in IL design and process optimization. Additionally, it highlights techno-economic analysis and life cycle assessment for evaluating the economic feasibility and environmental sustainability of IL-based biorefineries.
In this study, biomass chitosan (CS) was used as the raw material and potassium tetraxalate dihydrate (KH3C4O8·2H2O) as the activator. Porous carbon material (CK-M-T) was prepared by one-step activation method for efficient CO2 capture. The synergistic regulatory mechanism of activation temperature (600–800℃) and activator ratio (CS / KH3C4O8·2H2O mass ratio 1:3 − 1:5) on the microstructure, and surface chemical properties of materials was systematically investigated. The specific surface area and micropore volume of the CK-0.25-700 (prepared with a CS / KH3C4O8·2H2O ratio of 0.25 and pyrolysis temperature of 700 °C) are the highest, reaching 967 m3/g and 0.44 cm3/g respectively. Its three-dimensional disordered porous structure (SEM/TEM) and abundant micropores (1–3 nm) provide ideal channels for CO2 adsorption. At 273 K/298 K, the CO2 adsorption capacity of CK-0.25-700 reached 129.78/77.47 cm3/g, which was significantly better than that of samples under other conditions. The IAST model calculation shows that its selectivity for CO2/N2 (10/90) reaches 20 (298 K, 1 bar). The isosteric heat of adsorption (25.4–27.8 kJ/mol) confirmed that physical adsorption was dominant, leading to low regeneration energy consumption. After 20 adsorption-desorption cycles, the adsorption capacity remained stable, demonstrating outstanding cyclic stability-further confirming the material’s practical applicability. This work provides a new strategy for developing environmentally friendly and efficient porous carbon CO2 adsorbents. The mild and environmentally friendly activation property of KH3C4O8·2H2O makes it a promising alternative to traditional corrosive activators, promoting the application of biomass carbon materials in the field of carbon capture.
The rapid expansion of the global açaí (Euterpe oleracea) market has led to an alarming increase in waste generation, particularly seeds and fibers, posing significant environmental challenges. This review explores innovative strategies to repurpose these residues through cutting-edge technologies, including nanotechnology for nanocellulose production, microbial fermentation for biopolymer synthesis, and green extraction methods for obtaining bioactive compounds. Emphasis is placed on the development of high-value-added products such as biodegradable plastics, biomaterials, and renewable energy sources, aligning with the principles of the circular economy. Additionally, the review highlights the socioeconomic potential of these innovations and their role in mitigating environmental impacts. A focus is given to the need for sustainable practices and policy-driven initiatives to maximize the value of açaí residues, calling for solutions to overcome technological and economic barriers while promoting sustainable development in the Amazon region.
A simple lignocellulosic biomass fractionation strategy using lactic acid as a medium was investigated with miscanthus as a reference feedstock. Lactic acid, a biobased and safe medium, offers a simple process. Two triggers were identified to improve the lignin recovery yield: temperature increase (from 100 to 125 °C) or addition of catalyst acid (either HCl, H2SO4, or p-toluene sulfonic acid, 0.1 N) allowed energy savings. Without process optimization, at 125 °C, the acidity of lactic acid was sufficient for achieving 65
A three-year field experiment was conducted (2019–2021) using biofuel ash (BA) and granulated ash with 30
In this work, biodiesel was produced from high-free fatty acid Azadirachta indica (neem) oil using deep eutectic solvents as catalysts. Six DESs were synthesized and screened, having quaternary ammonium and phosphonium salts as hydrogen bond acceptors. The results show that the phosphonium-based toluene sulfonic acid-derived DES is the most active Brønsted-acid catalyst for FFA esterification. The process is systematically optimized by varying the oil: methanol molar ratio, esterification temperature, and catalyst loading. The optimum parameters obtained are 100 °C, a 1:5 oil-to-methanol ratio, and 3 wt
Biomass-derived geopolymers have attracted increasing attention as sustainable alternatives to ordinary Portland cement (OPC), valorizing agricultural, forestry, and industrial residues into low-carbon binders. A bibliometric analysis based on the Scopus database indicates a marked increase in research activity after 2018, with publication output peaking in 2023. China, India, Australia, and several European countries emerged as the leading contributors to this research field. Keyword mapping revealed four dominant research themes: strength and durability, biomass valorization, environmental remediation, and advanced applications such as 3D printing and composites. A critical review of representative studies showed that agricultural ashes, including rice husk ash (RHA) and sugarcane bagasse ash (SCBA), have demonstrated compressive strengths ranging from 30 to 72 MPa under different mix designs and curing conditions. Forestry residues, particularly wood fly ash and lignin, improved sulfate resistance and achieved adhesive bonding strengths of up to 3.8 MPa, while industrial biomass wastes, including olive stone bottom ash (OSBA) and paper sludge, reported compressive strengths of 18–43 MPa and phosphate removal efficiencies of up to 98
Dried fibres of Triumfetta cordifolia stem barks were modified by a non-thermal plasma discharge of the glidarc type and characterized by FT-IR, XRD, SEM, and pHPZC. Studies on the influence of solution pH, adsorbent dosage, initial pollutant concentration, and adsorbent particle size on the adsorption of crystal violet (CV) and ibuprofen (Ibu) were performed. The results indicated that the plasma-modified biomass outperformed significantly better than the unmodified biomass-derived adsorbents. The kinetics and isotherms of the adsorption process using pristine and plasma-modified fibres were quantified and modeled. The kinetic curves showed a good fit to the pseudo-second order model and Elovich model for CV and Ibu adsorption, respectively, with equilibrium reached after 60 min. The ideal plasma-modified adsorbent ECM exhibited maximum adsorption capacity of 15.90 mg/g for CV and 90.36 mg/g toward Ibu.The Liu isotherm model was found to be the best fit to the experimental data and, its equilibrium constant was used to determine the adsorption thermodynamic parameters for both pollutants. The determined parameters, including enthalpy change (ΔH° < 0), entropy change (ΔS°>0), and Gibbs free energies change (ΔG° < 0) suggested an exothermic, random, and spontaneous nature of the adsorption process in the temperature range of 298–323 K. Kinetic models and thermodynamic studies suggested multilayer exposure with both physical and chemical forces simultaneously controlling the adsorption of CV and Ibu on the ECM adsorbent. Also, the revival test of the CV- or Ibu-laden adsorbent unveiled a high desorption efficiency up to four adsorption–desorption cycles.
The growing demand for sustainable bioenergy storage materials highlights the need for mechanically stable briquettes with high energy efficiency; however, existing studies often lack systematic optimization of processing parameters governing these properties. In particular, the combined effects of moisture content, binder ratio, and compaction pressure on biochar–cardboard briquettes remain insufficiently understood. To address this research gap, this study employs the Box–Behnken Design (BBD) in conjunction with Response Surface Methodology (RSM) to optimize the production conditions of biochar–cardboard briquettes, focusing on three critical process parameters: humidity (10–20
Developing biodegradable polymer films from renewable resources has become a promising strategy for reducing plastic pollution while promoting the valorization of agricultural and food industry waste. In this study, potato starch-based biofilms (BS) were fabricated, and starch-based films were reinforced with natural polymers derived from organic waste, including partially hydrolyzed cellulose from banana peels (BSC), chitosan and chitin from shrimp shells (BSC1 and BSC2), and collagen from chicken feet (BSC3). The physical, chemical, mechanical, and morphological properties, as well as the chemical resistance and biodegradability of the fabricated films. FTIR analysis confirmed successful intermolecular interactions between the starch matrix and the reinforcing biopolymers, while SEM imaging revealed distinct morphological variations depending on the reinforcement type. Mechanical testing demonstrated that the cellulose-reinforced film (BSC) achieved the highest tensile strength of 8.23 ± 0.05 MPa, a significant improvement over the pure starch film (3.19 ± 0.34 MPa). The chitin-reinforced film (BSC2) exhibited the maximum elongation at break (85.0 ± 1.06
