Biomass Conversion and Biorefinery最新文献

Municipal wastewater in Tanzania is often discharged without adequate treatment, leading to severe environmental pollution. This study explores the potential of unmodified banana peel as a low-cost, eco-friendly biosorbent for reducing turbidity (TB) and chemical oxygen demand (COD) in municipal wastewater. A Box-Behnken Design of Response Surface Methodology (RSM) was used to optimize operating conditions, including mixing time (10–60 min), pH (4–10), and banana peel dosage (5–20 g). The process achieved 93% TB reduction and 79% COD reduction at optimal conditions of 55 min, pH 4.8, and 9 g/L dosage. The adsorption process followed the Langmuir isotherm model, indicating monolayer adsorption, and pseudo-second-order kinetics, suggesting chemisorption. With sorption capacities of 21.61 mg/g (TB) and 11.37 mg/g (COD), banana peels present a sustainable solution for wastewater treatment. This study provides a practical alternative for resource-limited settings, aligning with circular economy and green chemistry principles. Further research on scalability and long-term biosorbent reusability is recommended.

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This study presents the synthesis of an adsorbent material for the removal of brilliant green (BG) dye from aquatic systems using a composite (hereinafter, CTO/PC-HA) composed of chitosan and chemically modified pineapple (Ananas comosus) crown biomass via nitric acid (HNO₃). Response surface methodology (RSM) was applied to examine the impact of three variables on BG dye adsorption: A: CTO/PC-HA dosage (0.02–0.08 g), B: pH (4–10), and C: duration (10–40 min). The key parameters for BG dye removal were optimized using a desirability function approach, yielding optimal conditions (CTO/PC-HA dosage = 0.055 g, solution pH = 9.7, and contact time = 39.3 min). A maximum dye removal efficiency of 87.75% was achieved under these conditions. The BG dye adsorption onto CTO/PC-HA followed the pseudo-first-order kinetic model, indicating physical interactions. The Temkin isotherm best described the adsorption process, indicating uniform binding energies across the CTO/PC-HA surface. The CTO/PC-HA composite exhibited a maximum adsorption capacity of 316.96 mg/g for BG dye. The hypothesized mechanism for the adsorption of the BG dye onto the CTO/PC-HA composite was based on electrostatic interaction, hydrogen bonding, and n-π stacking interaction. The results of this study demonstrate that CTO/PC-HA is a promising adsorbent for the treatment of wastewater contaminated with basic dyes. Furthermore, the findings highlight a green, sustainable, and environmentally friendly approach to synthesizing adsorbents derived from acid-modified lignocellulosic biomass and chitosan capable of efficiently removing cationic dyes from polluted water.

This study focused on optimizing the medium composition and cultivation conditions to boost the biomass production of Fructobacillus fructosus through statistical methods. The one-factor-at-a-time (OFAT) method was employed to screen carbon sources (dextrose, sucrose, fructose, starch, and lactose) and nitrogen sources (peptone, yeast extract, beef extract and their combinations, corn steep liquor, and ammonium chloride). Based on the OFAT results, four key factors were selected for the Response Surface Methodology (RSM) to determine their significant impact on biomass yield. Fructose, yeast extract, ammonium chloride, and potassium phosphate monobasic were identified as critical factors and subjected to response surface methodology using the Central Composite Design (CCD) method of analysis. The optimal medium composition obtained through RSM consisted of 22.5 g/L fructose, 8 g/L yeast extract, 2.5 g/L KH₂PO_4, and 2.5 g/L ammonium chloride, and the optimized physical parameters included a temperature of 37.5 °C, pH 4.5, an incubation period of 36 h, and an inoculum size of 12.5% (v/v). Under these optimized conditions, the biomass yield of F. fructosus reached an absorbance of 2.295 at 600 nm with a CFU count of 6.711 log CFU/mL, compared to the unoptimized medium with an absorbance of 1.550 at 600 nm and 5.324 CFU/mL, with a 1.48-fold increase when compared with the native MRS medium. The highest biomass yield was at 37.5 °C, pH 4.5, an incubation time of 36 h, and an inoculum size of 12.5 (%v/v). In conclusion, the mass production of F. fructosus was significantly enhanced, yielding higher biomass than in the standard MRS medium, highlighting its potential for scalable industrial applications in probiotic and functional food development.

Passion fruit (PF) waste causes significant environmental pollution. Utilization of PF extracts as oxidative stabilizer and corrosion inhibitor is barely addressed. In this study, GC-MS analysis of PF rind and seed methanolic extracts (yellow and purple varieties) identified a range of phytochemicals such as, 3-hydroxybutyric acid, propanoic acid, propylene glycol, maltol, piperazine, homopiperazine, tetradecanoic acids, hexadecanoic acid, etc. Three biodiesel samples were synthesized from neem seed oil, karanja seed oil, and waste cooking oil for this study. Their transesterification efficiency was found to be above 98% meeting EN 14,214 specifications. The acid value (0.41–0.48 mg KOH/g), pour point (6–9 °C), cloud point (11–15 °C), flash point (148–163 °C) and calorific value (31–33 MJ/Kg) of the biodiesel were in accord with ASTM (6751–02) limits. All biodiesel were found thermally stable (172–191 °C) confirmed from the TGA analysis. Oxidative stability of different biodiesel was evaluated following ASTM D7545 method, incorporating various PF extracts. Rind and seed extracts of yellow passion fruit (YPF) and seed extract of purple passion fruit (PPF) improved biodiesel’s oxidation stability by two-fold compared to neat biodiesel. Further, the corrosion inhibition efficiency of PF extracts on mild steel (MS) in different biodiesel was found to be noteworthy (inhibition efficiency of 71–74%) as determined by the weight loss method. Further, the XRD, EDX, and SEM analyses demonstrated the corrosion protective effects of the PF extracts on MS, revealing changes in crystallographic structure, elemental composition, and surface morphology that corroborated the formation of a protective layer. This study showcases a sustainable strategy for harnessing phytochemical-rich extracts from PF bio-waste to enhance biodiesel’s oxidative stability and reduce its corrosive effects.

Agro-industrial and urban residues are promising feedstocks for the production of fermentable sugars, which serve as precursors for second-generation (2G) ethanol. This study evaluated banana pseudostem (BPS), guava seed cake (GSC), and urban tree pruning (UTP) residues to determine the optimal conditions for maximizing xylose and glucose yields. Both monosaccharides can be fermented by microorganisms to produce 2G ethanol, contributing to an increased supply of this biofuel. A 2³ factorial experimental design was employed to assess xylose and glucose solubilization, performed via acid pretreatment with sulfuric acid (H₂SO₄), followed by enzymatic hydrolysis of the pretreated biomass. During pretreatment, xylose solubilization reached 5.66 g.L⁻¹ in BPS, 9.24 g.L⁻¹ in GSC, and 8.13 g.L⁻¹ in UTP residues. Statistical analysis identified the optimal pretreatment conditions for BPS and GSC as moderate temperature, reaction time, and acid concentration (140 °C, 40 min, and 3.5% (w/v) H₂SO₄). In the subsequent enzymatic hydrolysis step (Cellic Ctec 2, 12 FPU.g^− 1, 50 °C/24 h, 140 rpm), maximum glucose solubilization was 8.6 g.L⁻¹ for BPS, 2.33 g.L⁻¹ for GSC, and 1.06 g.L⁻¹ for UTP residues. According to the data, BPS is the most promising material for the highest yield of total fermentable sugars, excelling primarily in hexoses. However, UTP also stands out for its production of pentoses (xylose and others). These findings demonstrate efficient xylose and glucose solubilization, optimizing process conditions and underscoring the potential of the selected residues and applied pretreatment techniques.

Novel hydrogels are increasingly welcoming, especially for electronic wearable strain sensor applications. This study was to fabricate polyacrylic acid/cellulose nanocrystals/multi-walled carbon nanotubes (PAA/CNCs/MWCNTs) nanocomposite hydrogels. The CNCs in the hydrogels acted as reinforcing fillers to strengthen the mechanical properties of the hydrogels. In this study, CNCs were extracted from raw kapok fibres using different types of DESs. The mechanical properties of the nanocomposite hydrogels were examined by subjecting the samples to swelling and tensile tests. The hydrogel with 5 mg of choline chloride-oxalic acid (ChCl-OA)-CNCs and 5 mg of MWCNTs (H6) exhibited an excellent swelling behaviour of 39% equilibrium swelling ratio after 70 h and an outstanding tensile strength of 0.180 MPa (1223.5%). The hydrogel also exhibited a satisfactory self-healing efficiency of 88.33% after 6 h of healing. The conductive hydrogel underwent sensing performance tests to study its electrical properties. It evidently detected finger joints, twisting, and uniaxial motions with positive relative resistance changes while maintaining structural integrity, indicating high sensitivity, responsiveness, and toughness. The hydrogels demonstrated notable mechanical strength, stretchability, resistance to swelling, and sensitivity to strain. Thus, it was concluded that the PAA/CNCs/MWCNTs nanocomposite hydrogels are potential candidates for electronic wearable strain sensors in biomedical sectors.

An investigation has been performed for alcoholic fermentation from bread waste. Some concentrations of bread waste-derived biochar (BWB) have been selected to optimize ethanol concentration. For this, three biochar concentrations have been used: 2.5, 5 and 7.5 g/L. Different parameters have been followed up and evaluated: yeast concentration, pH, ethanol concentration, and total sugars. It has been found that elementary analysis of biochar revealed a high percentage of carbon (57.92%) and oxygen (23.34%). Moreover, the addition of biochar to the bread waste hydrolysate resulted in a significant increase in the bioethanol concentration; it varies from 85 g/L to 110 g/L for a biochar concentration of 7.5 g/L. This is due to the fact that biochar provides a high surface for yeast to be fixed and grow, hence increasing their ability to ferment sugars into ethanol. This is significantly high when comparing it to the fermentation process without adding biochar, which is only about 85 g/L. The hydrolysate medium has a mixture of sugars that are easily transported to the cell membrane and then assimilated to reach the values of 78 g/L, 70 g/L, and 66 g/L for biochar concentrations of 2.5, 5 and 7.5 g/L, respectively. These findings highlight the potential of bread waste-derived biochar to enhance bioethanol production, offering a sustainable and efficient approach to biofuel production. Furthermore, this study serves as one of the pioneering researches into the application of biochar in alcoholic fermentation.

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A large portion of the global population is susceptible to drinking water tainted with fluoride. However, eliminating fluoride remains a problem, particularly in isolated rural areas, as existing methods necessitate careful supervision and are equally ineffective because of the energy crisis and economic issues. Adsorption techniques are shown to be the most effective for removing fluoride in low-resource setting areas. This study prepared activated carbon from Pinus Roxburghii cones via pyrolysis at 650 °C and KOH activation at 800 °C. Scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) microanalysis were conducted to scrutinize activated carbon’s surface structure and surface-bound functional groups. The response surface methodology was developed with a central composite design; CCD suggested 30 experimental runs conducted using a batch study. The four influencing parameters, such as contact time (10–70 min), the dosage of adsorbent (0.2–10 gL^− 1), initial fluoride concentration (5–25 mgL^− 1), and pH (4–10), were considered. Additionally, the Freundlich isotherm was also investigated. The results showed that Pinus Roxburghii had a fluoride removal efficiency of 98.97% at an optimum adsorbent dosage of 5.1 gL^− 1, initial fluoride concentration of 14 mgL^− 1, and pH of 6.5, with 30 min of contact time. Therefore, Pinus Roxburghii cones activated carbon is a potentially effective adsorbent for fluoride eradication from water. It is applicable in adsorption-based water treatment plants under optimized conditions to demonstrate its feasibility for large-scale application.

The global energy crisis and climate change have intensified the search for sustainable alternatives to fossil fuels, with sugarcane bagasse emerging as a promising biomass feedstock. This study investigates the integrated pyrolysis and pelletization of Suphanburi-50 sugarcane bagasse to optimize bioenergy production. Fast pyrolysis (100 °C/min) yielded 57.4% bio-oil with 20.4 MJ/kg heating value (HHV), while slow pyrolysis (5 °C/min) produced 60.7% biochar (30.0 MJ/kg) and energy-rich syngas (5.59 MJ/m³). Bio-oil characterization identified oxygenated compounds, including furans (27.28%), phenols (19.80%), and carboxylic acids (14.40%), while biochar showed enhanced fuel properties suitable for co-combustion. Kinetic analysis revealed an activation energy of 44.42 kJ/mol, confirming suitability for slow pyrolysis. Pelletization at 12% moisture achieved high durability (96.8 Shore A), a bulk density of 848 kg/m³, and HHV of 18.4 MJ/kg, and met ENPlus and Thailand Pellet Standards. Economic analysis showed pelletization as the most viable small-scale option (NPV: 4.5 million THB, IRR: 61%, PBP: 0.79 years), while slow pyrolysis offered higher long-term returns (NPV: 8.8 million THB, IRR: 38%). Fast pyrolysis, despite higher oil yield, had lower profitability (NPV: 5.8 million THB, IRR: 29%). The results demonstrate that integrated thermochemical conversion can enhance bagasse valorization, with pelletization being optimal for SMEs and slow pyrolysis for diversified bioenergy production.

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In adsorption technology, understanding the factors that influence adsorption efficiency and optimizing the process parameters are essential for achieving optimal system performance. In this line, the present work focused on optimization of inevitable process parameters, such as initial metal concentration, pH, contact time, and adsorbent dosage to enhance the sorption of hexavalent chromium [Cr (VI)] using Purpureocillium lilacinum (P. lilacinum) fungal biomass. Response surface methodology (RSM) and artificial neural networks (ANN) were employed for optimizing the process parameters. Besides, adsorption equilibrium, kinetics, thermodynamics, and adsorbent regeneration studies were also investigated. The maximum sorption efficiency, 97.71%, for Cr (VI) removal was achieved at an initial metal concentration of 20 mg/L, adsorbent dosage of 0.5 g/L, pH value of 4, and contact time of 40 min. The results of the ANN model demonstrated that ANN has superior predictive power than the RSM model, with R² of 0.9936 for ANN and 0.9788 for RSM. The adsorption process was well-fit to Langmuir and three-parameter isotherms with R² > 0.995. The kinetic investigation indicated that the biosorption was a chemisorption process and the data were observed to be fitted best with Elovich’s kinetic model. The results of thermodynamic analysis revealed that biosorption was favorable and exothermic. Further, the treatment with NaOH showed a superior performance in the regeneration of adsorbent material. Different characterizations on the adsorbent revealed the presence of active sites, cavities, and various functional groups were responsible for biosorption.