Biomass Conversion and Biorefinery最新文献

The increasing global demand for sustainable and low-carbon energy sources has driven significant interest in biomass-based biofuels. Industrial waste algae, an abundant, renewable, and non-food bioresource, presents a promising feedstock for thermochemical conversion due to its high lipid content, rapid growth rate, and carbon sequestration potential. This study investigates the hydrothermal liquefaction (HTL) and hydrothermal gasification (HTG) processes for converting industrial waste algae into biofuels, focusing on optimizing bio-oil yield, hydrogen production, and pollution index reduction. The influence of key process parametersincluding temperature, pressure, reaction time, catalyst loading, and solvent-to-biomass (S/B) ratioon bio-oil and hydrogen yield was systematically analyzed through experimental and computational approaches.HTL experiments were conducted at temperatures between 200 and 420 °C, pressures up to 20 MPa, and reaction times ranging from 30 to 90 min, utilizing Ca(OH)₂ as a catalyst. The optimal conditions (300 °C, 50 bar, 60 min, 3% catalyst, and an S/B ratio of 13.3) resulted in a bio-oil yield of 39.6% with a higher heating value (HHV) of 35.8 MJ/kg. Similarly, HTG experiments performed at temperatures > 375 °C and pressures > 22 MPa demonstrated that 350 °C, 20 MPa, and 60 min reaction time yielded 81.6% hydrogen with a pollution index (PI) of 9.3% when processed with 5% ZnO catalyst. The syngas composition was characterized using gas chromatography-mass spectrometry (GC-MS), revealing an H₂-rich gas phase with minimal CO₂ emissions.To enhance process efficiency, an AI-driven Tunable Decision Support System (TDSS) and Tunable Recommendation System (TRS) were developed, integrating Supervised Multivariate Random Forest (SMVRF) and Adaptive Multivariate Random Forest (AMVRF) models. These machine learning models analyzed large-scale experimental datasets and demonstrated > 94% accuracy in predicting optimal process conditions. The AI framework effectively correlated biomass composition with conversion efficiency, enabling real-time decision-making for improved biofuel yield and energy recovery.This study establishes that industrial waste algae is a viable and sustainable feedstock for biofuel production through HTL and HTG, offering a renewable energy alternative with lower carbon emissions. The integration of machine learning-driven optimization significantly enhances process efficiency, reducing experimental costs while maximizing biofuel yield. These findings contribute to the advancement of biorefinery technologies and support the scalability of hydrothermal biofuel production, paving the way for sustainable, AI-assisted industrial bioconversion.

Sulfate-rich wastewater poses significant environmental and health risks, as the presence of heavy metals amplifies toxicity through synergistic effects, complicating treatment processes. An UASB reactor was operated for eight months to investigate the synergistic effects of co-metals on in-situ sulfide control under varying COD/SO₄²⁻ ratios and hydraulic retention times (HRTs). The combined toxicity of nickel (Ni2+) and copper (Cu2+), each at an individual concentration of 150 mg/L, reduced methane production by 51.3%; however, metal precipitation strategies effectively mitigated this toxicity, resulting in improved sulfide control and enhanced methane production. At relatively low COD/SO₄²⁻ ratios (1-0.5), methanogenic and sulfate-reducing bacteria (SRB) demonstrated syntrophic acetate oxidation, with a maximum usable Cu²⁺ concentration of 0.825 mmol/L. The maximum sulfide precipitation of 683.81 mg/L was achieved at a COD/SO₄²⁻ ratio of 0.5 and a 12-h HRT. The system demonstrated high efficiency in removing both COD (92.7%) and sulfate (94.5%) while achieving an energy recovery rate of 42.38 mmol CH₄/L. With nickel and copper acting synergistically, the reactor demonstrated stable performance, achieving enhanced sulfate and COD removal efficiency while effectively mitigating sulfide toxicity and improving methane production. These findings highlight the technical feasibility of metal supplementation for in-situ sulfide control and the optimization of anaerobic treatment of sulfate-rich wastewaters.

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This study presents the preparation and characterization of novel chitosan/sodium caseinate bio-nanocomposite films doped with green tea extract and boron nitride nanoparticles. Different films were prepared with varying amounts of sodium caseinate, green tea extract, and boron nitride. Moisture content, water and vapor swelling, pH-dependent solubility, optical and color properties, antimicrobial activity, mechanical strength, total phenol, and antioxidant properties of films were studied. As the sodium caseinate ratio increased, the moisture content, swelling degree, tensile strength, and elongation decreased. The results indicated that green tea extract and boron nitride improves properties of the films. The addition of GTE and BN significantly increased mechanical strength and decreased moisture content. The lowest moisture content of 16.67%, the highest total color difference of 27.58, and the highest antioxidant activity of 93.6% were obtained with 1 vol% of green tea extract loaded chitosan/sodium caseinate films. The lowest water swelling degree of 51.22% and the highest tensile strength of 11.35 MPa were obtained with 1 wt% boron nitride-loaded chitosan/sodium caseinate films. The incorporation of boron nitride increased the antimicrobial effect, while the green tea extract additive increased the degradation rate in soil.

Hydrothermal liquefaction (HTL) and co-liquefaction (co-HTL) of corn industry wastes (corn stover, CS; corn cob, CC; and nejayote, NJT) were evaluated at low intensity energy conditions (250 °C and 0.5 MPa N₂) for the production of bio-crude and biochar. Individual feedstocks, binary and ternary blends, were formulated. Most blends exhibited a clear synergistic effect, particularly those containing NJT, which showed a possible catalytic role, increasing bio-crude yields by up to 14.93 wt%. The ternary NJT–CS–CC (1:1:2) blend presented the highest synergistic enhancement (7.04 wt%), producing bio-crude with high energy recovery (ER, 23.47%) and higher heating value (29.76 MJ/kg). CC and CS generated the highest biochar yields (29.18–30.86 wt%) and ER (36.55–42.29%). All biochars exhibited mesoporous structures suitable for adsorption, with the best surface properties obtained from CS, NJT, and one ternary blend. The bio-crude contained valuable oxygenated compounds and esters relevant to fuel and chemical applications. Overall, co-HTL at moderate temperature combined with NJT significantly enhances bio-crude yield and quality through synergistic interactions, whereas individual wastes are better suited for biochar production. This work helps close key knowledge gaps and encourages the evaluation of sustainability and life cycle assessment of the Mexican corn flour industry.

This study explores utilization of coffee leaves extract for development of UV-resistant cotton fabric which is consider as an underutilized agricultural by-product. The research aims to provide an eco-friendly alternative to synthetic UV-blocking agents by optimizing dye extraction and mordanting conditions. The dyed fabrics exhibited significant enhancements in UV protection, tensile strength (154.17 N warp, 103.95 N weft), thickness (0.236 mm), drapability (122.17%), moisture regain (13.65%), and air permeability (26.20 cm³/cm²/s). Structural modifications were confirmed via Scanning Electron Microscopy (SEM), Energy Dispersive X-ray (EDX), and X-ray Diffraction (XRD). Among mordants, copper sulfate-treated fabrics demonstrated the highest UPF value of 90, confirming their superior UV-blocking capability and myrobalam is also considered as natural mordant suitable for coffee leaves extract. This study highlights the potential of repurposing coffee leaf waste in textile applications, contributing to sustainable and bio-based UV protection solutions.

This study investigates the use of single-chamber microbial fuel cells (MFC) with commercial sugar as an organic substrate and benzene as an organic pollutant. The reaction runs for 50 days, aiming to enhance electron generation and water treatment efficiency. Electrochemical analysis revealed a voltage of 300 mV after 37 days, with a power density of 3.42 mW/m². The calculated internal resistance was found to be 500 Ω. Initial conductivity was 1755 mS/cm, increasing to approximately 4123 mS/cm by day 40. Optimal microbial activity and electron transfer efficiency were observed between days 30 and 38, corresponding to the peak power density. Specific capacitance on day 40 was 1.8 × 10^− 4 F/g, indicating gradual biofilm development and maturation. Electrochemical impedance spectroscopy (EIS) showed a favorable trend in electron transfers, and benzene degradation efficiency reached 83.33%. Scanning electron microscopy-energy dispersive X-ray (SEM-EDX) analysis confirmed healthy biofilm development. Tatumella citrea, Pectobacterium zantedeschiae, and Serratia plymuthica were some of the most dominant bacteria involved in benzene degradation and electron generation. The study also details the mechanisms of electron transfer, substrate oxidation, and future challenges, highlighting critical scientific outcomes and the potential of MFC for sustainable environmental solutions.

This study undertakes an exhaustive evaluation of the economics, and process efficiencies in producing bioethanol from sugarcane, cassava, and yam within the Colombian context. Non-conventional starchy crops were considered in this study with low agronomical technicity and high starch content. Gasification technology was considered an alternative to steam systems for energy coproduction. The simulation of ethanol production was carried out in Aspen Plus V9®. Numerical models were obtained via Response surface method (RSM) for economic response evaluation depending on feedstock price and applied tax rate. Sugarcane remains the superior feedstock, with a net present value (NPV) of ($22,211,942.44). Cassava and yam, despite facing several challenges leading to negative NPVs of ($499,753,466.22) and ($173,103,763.14) respectively, exhibited commendable ethanol yields and the capacity for electricity co-production. The study revealed an electricity production potential of up to 171.330 kWh for yam, compared to 151.020 kWh for sugarcane. Achieving a positive electric balance remains a challenge, with the best-case scenario being sugarcane at 77% electric supply of its requirements. While sugarcane remains the predominant choice for bioethanol production in Colombia (0.68 USD/l), cassava (2.28 USD/l) and yam (1.11 USD/l) present viable alternatives under strategic enhancements in agricultural productivity and cost management.

Acorn cupules are the structures that originally protect and connect the acorn to the tree. Currently, they are considered a residue of the acorn sector. In the present work, cupules from six Portuguese autochthonous species of oak (Quercus suber, Q. rotundifolia, Q. pyrenaica, Q. faginea, Q. coccifera, Q. robur) were chemically (summative composition, lignin composition, apolar extracts composition, phenolic contents, and antioxidant activity of polar extracts) and thermally (proximate analysis and higher heating value) analysed to enable the evaluation for best deconstruction pathways and end purposes toward a full use of these available resources. The results revealed variations among the six species for every parameter examined. Q. robur stood out for the amount of total extractives (37.2%) and content in condensed tannins (235 mgCE/g_Ext). Q. coccifera demonstrated a higher percentage of lignin (34.7%), and Q. rotundifolia was the species with a higher percentage of polymeric sugars (50.2%) and flavonoids (450mgCE/g_Ext). Q. suber showed the highest antioxidant capacity (AAI = 7.7; 1.9gTE/g_Ext) and the highest content in total phenols (622mgGAE/g_Ext). Cupule’s lignin polymer proved to have a low S/G ratio (from 0.4 to 0.7). Higher heating value was similar for all six species (19.4 to 20.6 MJ/Kg), but Q. suber had a higher fixed carbon content, 28.2%, compared to 21.5% (Q. coccifera and Q. pyrenaica) to 25.4% (Q. rotundifolia). These findings highlight the potential of acorn cupules as a source of lignin or hemicellulose oligosaccharides. Q. suber demonstrated a very high antioxidant capacity with potential to be utilized in the cosmetic or pharmaceutical industry.

Increasing disposal of toxic dye wastewater from various industries causes a major environmental concern. This study investigates the utilization of Ziziphus lotus seeds (ZS) as a lignin source for preparing activated carbon (AC) and treating Congo red (CR) dye with this AC. Potassium hydroxide (KOH) was used as an activating agent. The optimization was performed using Response Surface Methodology (RSM) to investigate the impact of the impregnation ratio A, the activation time (min) B, and the activation temperature (°C) C. The optimal AC was characterized by Attenuated Total Reflectance Fourier-Transform Infrared (ATR-FTIR) spectroscopy, X-ray diffraction (XRD), and Scanning Electron Microscopy (SEM), ZS was also characterized by ATR-FTIR. The batch adsorption of CR dye onto the optimal AC, by varying the pH, the contact time, the temperature, the AC dose, and the initial concentration of CR. The results show that the maximum adsorption rate (85.34%) was reached under activation at 550 °C, for an activation duration of 120 min and an impregnation ratio of 3:1. For the adsorption experiments, the optimal operating conditions were pH = 4, a contact time of 80 min, an adsorbent dose of 0.4 g/L, and a solution temperature of 50 °C. The equilibrium data were revealed to be more accurately described by the Freundlich isotherm model (R² = 0.996). Furthermore, the kinetics were found to be consistent with a pseudo-second-order model at the initial concentrations of 20 mg/L and 40 mg/L.

This study focuses on the sustainable production of hydrogen and the simultaneous reduction of emissions through the catalytic processing of ammonia-treated Jatropha oil blends, integrated with metal-organic frameworks (MOFs) and graphene quantum dots (GQDs). The Jatropha oil blend, comprising 70% Jatropha oil and 30% palm oil, was treated with 5% ammonia at 100 °C for 2 h, altering its chemical structure to enhance reactivity and catalytic efficiency. Zinc-based ZIF-8 MOFs synthesized through a solvothermal process exhibited a surface area of 920 m²/g, while GQDs prepared via hydrothermal treatment had a size range of 2–5 nm and a surface area of 420 m²/g. These catalysts facilitated a hydrogen yield of 165 mmol/g at 500 °C and 7 wt% catalyst concentration, demonstrating a significant increase compared to 95 mmol/g at 3 wt% catalyst concentration under similar conditions. Emissions of CO₂ and unburned hydrocarbons were reduced by 35% and 42%, respectively, due to the optimized catalytic properties of the MOFs and GQDs. X-ray diffraction (XRD) analysis confirmed the crystalline structure of the catalysts, while ammonia treatment improved feedstock stability and reactivity by increasing the availability of reactive hydrogen atoms. The synergy between MOFs and GQDs enabled higher hydrogen yields and lower emission levels by enhancing reaction kinetics and reducing carbon-carbon bond strength. These findings underline the potential of ammonia-treated bio-oils with advanced catalysts to serve as a sustainable and efficient pathway for hydrogen production, offering a significant step toward reducing carbon emissions and advancing renewable energy technologies.