Biomass & Bioenergy最新文献

A series of Mo₂N particles supported on nitrogen-doped carbon (Mo₂N@NC) catalysts for guaiacol hydrodeoxygenation were synthesized in situ through a one-step method employing dopamine as C and N resources and ammonium molybdate as Mo resource, respectively. During synthesis, molybdate ions are adsorbed on dopamine because of a complexation between them; then dopamine/molybdate ions/TMB/F127 nanoemulsions are formed. After polymerization, growth, drying, and carbonization, Mo₂N particles supported on nitrogen-doped carbon catalysts are obtained. Because of the interaction between Mo and N, Mo₂N particles are anchored onto the support, preventing the aggregation of Mo₂N during carbonization. As a result, ultrafine Mo₂N particles with a size of 1.0–1.3 nm are highly dispersed on Mo₂N@NC catalysts. The guaiacol hydrodeoxygenation for these Mo₂N@NC catalysts was performed at 280–380 °C, a H₂ flow rate of 80 mL/min and different pressures and weight hourly space velocities. Among them, Mo₂N@NC with a Mo₂N loading of 40 % presents the highest guaiacol conversion (99.9 %) and aromatic hydrocarbon selectivity (80.2 %), which is also better than Mo₂N/C with a Mo₂N loading of 40 % prepared by the wet impregnation method.

Hydrogen energy derived through biomass gasification is considered as one of the most sorted sustainable sources of renewable energy. This process enhances the H₂ production from biomass in the presence of specific catalysts. Among different kinds of models that have been employed for this process, ML models adept at approximating non-linear functions and facilitate outcome prediction without detailed mathematical descriptions. Thus, the current work focuses on understanding structural-composition-operating-target property relationships, and integrated catalyst and process modelling using ML framework for thermo-catalytic biomass gasification to H₂ production, and demonstrates outliers handling, data normalization for efficient handling of data-driven modelling with non-linear database. Linear, tree-based, kernel-based, and ANN models were developed with 589 datapoints screened from the 59 relevant papers with 24 inputs and 4 outputs (H₂, CO, CO₂, and CH₄ as vol. %). Performance of these models are evaluated through 5-fold cross-validation and test data with the help of statistical measures. ANN with Basian-regularization learning algorithm using tan-sigmoid activation function in both layers, resulted superior performance in prediction of H₂ production (RMSE = 6.85 & R² = 0.80) and other output gases with high accuracy (i.e., minimum deviation from experimental data) compared to other ML models. Further, using the best ML model, input contribution and PDP analysis were performed to interpret the significance of predominate input parameters affecting on the product composition. Feature contribution analysis reveals that temperature, S/B ratio, catalyst support type, and sulphur content in biomass are significant parameters for enhancing H2 production from catalytic-biomass gasification, and PDP analysis discloses their optimal operating region.

In this study, a continuously anaerobic two-stage pilot plant was established for bioenergy production, comprising 5 major pieces of equipment: a mixing tank, 1st anaerobic digester (AD), 2nd AD, sediment tank, aeration tank, and final sediment tank, all operating at ambient conditions. The operation of the continuously anaerobic two-stage pilot plant was automatically controlled by a programmable logic controller (PLC) using a designed control logic concept to set the hydraulic retention time (HRT) and inlet substrate concentration. The organic loading rate, pretreatment of hydrolysis pressure, and microbial community analysis were investigated for their effects on biogas production performance using different substrates: soybean residue (SR) and food waste hydrolysate (FWH), respectively. It was found that the peaks of biogas production rate on daily volumetric feeding were 1.20 m³·m⁻³·d⁻¹, and the biogas yield on VS added was 760 dm³·kg⁻¹ from food waste hydrolysate with a pretreatment hydrolysis pressure of 10 kg cm⁻², at an OLR in COD concentration of 3.56 kg m⁻³·d⁻¹, and an HRT of 11 days, respectively. The Methanobrevibacter genus was found to be abundant in the 1st AD, approximately 6.7 times more abundant than in the 2nd AD. The continuous anaerobic two-stage pilot plant was properly examined for its application in treating food waste and soybean residue with the goal of obtaining renewable bioenergy.

The quest for viable and scalable biofuel sources has been at the forefront of scientific innovation for the past three decades. Due to its rich chemical constituents, microalgal biomass has emerged as a pivotal sustainable and scalable feedstock for biorefineries. This comprehensive review critically analyzes the different types of microalgae feedstock, concurrent extraction technologies, bio-pre-treatment procedures, and the key chemical and physical parameters influencing lipid formation and algal biofuel production. We propose a novel approach of photo-initiated culturing of algal biomass using photobioreactors (PBRs) to address the limitations of concurrent space and time-related constraints. The innovative photo bio-refinery strategy presented herein aims to enhance sustainability factors while minimizing emissions, catering to the needs of futuristic non-electric vehicles. A comparative quality analysis of microalgae-derived biofuel against conventional fossil fuels and other biofuels is conducted, considering chemical, environmental, economic, and social perspectives. Furthermore, we elucidate the efficacy of bio-pre-treatment strategies such as dehydration, hydrothermal liquefaction, pyrolysis, and gasification in optimizing biofuel production. The proposed photo biorefineries exhibit the potential to yield a diverse range of value-added products, including biodiesel, biogases, bio-fertilizers, bio-pesticides, bio-alcohols, dyes, proteins, carotenoids, and drug vitals. This review provides a comprehensive framework for the development of sustainable and efficient microalgae-based biorefineries, paving the way for a greener and more economically viable future in the biofuel industry.

Compositional characterization of biomass is vital for the biofuel industry. Traditional wet chemistry-based methods for analyzing biomass composition are laborious, time-consuming, and require extensive use of chemical reagents as well as highly skilled personnel. In this study, near-infrared (NIR) spectroscopy was used to quickly assess the composition of above-ground vegetative biomass from 113 diverse, photoperiod-sensitive, biomass-type sorghum (Sorghum bicolor) accessions cultivated under field conditions in Central Illinois. Biomass samples were analyzed using NIR spectra collected in the spectral range of 867–2536 nm, with their chemical compositions determined following the National Renewable Energy Laboratory (NREL) protocol. Advanced spectral pre-treatment and band selection techniques were utilized to develop calibration models using partial least squares regression (PLSR). The models' effectiveness was assessed through cross-validation and independent data tests. The predictions for moisture, ash, extractives, glucan, xylan, acid-soluble lignin (ASL), acid-insoluble lignin (AIL), and total lignin were accurate and reliable, demonstrating the capability of NIR spectroscopy to provide rapid and precise characterization of sorghum biomass. The results demonstrated that NIR spectroscopy is an efficient tool for rapidly characterizing sorghum biomass, making it a sustainable option for screening desirable feedstock for biofuel or bioproduct production.

Biobutanol, a promising green alternative fuel, fermented from Clostridium acetobutylicum, while its high-cost and limited yield constraining its development. ABE (acetone-butanol-ethanol) and IBE (isopropanol-butanol-ethanol) are mixed fermentation products from non-edible biomass raw materials, using them together with water as alternative fuels will reduce industrial production costs and save fossil fuels. Therefore, this study conducted a multifaceted experimental evaluation on ABE/IBE mixed fuels with different water content, demonstrating that it has good water holding capacity when mixed with traditional fossil fuels. Taking ABE (3: 6: 1) as an example, its water holding capacity after mixing with diesel at 10–90 % is 0.37–7.83 % at 20 °C. Meanwhile, the particle size of ABE/IBE mixed fuels is about 2–30 nm, exhibiting a microemulsion with thermodynamic stability. The anhydrous or water-containing mixed fuel with the ratio of ABE (IBE) of 10%–50 % meets the range of the density and kinematic viscosity of diesel engine fuel. The mixed fuel is non-corrosive to copper without water, and a water content of about 3 % or higher will increase the risk of engine corrosion at 20 °C. Despite the addition of biofuel and water, studies on energy combustion performance and pollutant emission performance have found that appropriate addition of biofuel and water can produce higher power output and lower pollutant emissions than traditional fossil fuels, with ABE20W0.5 being the optimal. This study demonstrates the great potential of ABE and IBE as biofuels to achieve carbon neutrality goals, providing novel research direction for green alternative fuels in the future.

Synergy in the co-processing of lignocellulosic wastes and municipal biowaste (MB) can unlock their potential for biobutanol production. This study assessed the potential for biobutanol production through the co-processing of lignocellulosic waste and MB. Specifically, it compared the co-processing of paper waste with MB to that of garden waste and MB. Ethanol organosolv pretreatment served as a dual-function process for both pretreatment and detoxification purposes. Initial fermentation of hydrolysates from untreated paper waste using Clostridium acetobutylicum produced 0.9 g/L of acetone and ethanol but no detectable butanol. Organosolv pretreatment led to a significant increase in acetone and ethanol production but did not yield butanol. Co-processing paper waste with MB using organosolv pretreatment resulted in the production of 2.8–3.2 g/L butanol, along with increased acetone and ethanol production. Furthermore, co-processing a 1:1 (w/w) mixture of paper waste and MB under mild and severe pretreatment conditions produced 45.5 g and 43.4 g butanol, respectively, compared to 34.8 g and 14.4 g butanol when processing these waste streams separately. The study also explored the positive impact of co-processing garden waste with MB, a distinct lignocellulosic source, enhancing acetone-butanol-ethanol (ABE) yield by 27–40%. These findings highlight the potential of synergistic waste co-processing for achieving a more suitable balance of nutrients to enhance biobutanol and ABE production from biowastes. Additionally, the simultaneous treatment of lignocellulosic waste and municipal biowaste offers a simplified approach to waste processing, contributing to advancements in sustainable biomass utilization and bioenergy production.

The use of conventional petrochemical-based carbon precursors, high-energy pyrolysis-based carbonization processes, and difficulties in designing sustainable processes using activated carbon have hampered the sustainable production of activated carbon and its use in wastewater treatment processes. In this study, to overcome these limitations in the production and application of existing petrochemical-based activated carbon as a water treatment material, biomass-based kraft lignin was used as an eco-friendly carbon precursor. In addition, to increase process efficiency, activated carbon was prepared using energy-intensive microwave-assisted carbonization and applied to the dye wastewater removal process. First, kraft lignin was successfully converted into microporous activated carbon within 10 min through microwave-assisted carbonization and chemical activation processes. As a result, kraft lignin-derived activated carbon showed excellent adsorption capacity for MB of 543.82 mg/g and AO of 548.54 mg/g, respectively. In addition, through heat treatment using microwaves (low power conditions of 450 W, treatment within 2 min), it was possible to successfully achieve thermal decomposition of the adsorbed dye and recovery of the pores and texture properties of activated carbon. Finally, kraft lignin-derived activated carbon showed an excellent reuse efficiency of more than 97 %, even under the condition of reuse 5 times.

Furfural and levulinic acid are valuable platform compounds that can be produced by acid catalyzed conversion of sugars. Modified MCM-41 with different contents of silicotungstic acid (20 wt%-50 wt%) was successfully prepared via a wet impregnation method in order to regulate the ratio of Brønsted acid to Lewis acid. Among these catalysts, 40 wt% HSiW/MCM-41 with superior acid site density (Brønsted acid 59.35 μmol/g, Lewis acid 33.69 μmol/g) showed excellent catalytic activity as it exposed the most acidic sites and the ratio of Brønsted acid to Lewis acid reached 1.76. The conversion of biomass-based sugar was as high as 99.01 %, the maximum yield of furfural could reach 56.75 %, and the yield of levulinic acid could reach 18.88 % catalyzed by 40 wt% HSiW/MCM-41. This study provided new insights into the development of efficient and sustainable catalytic systems for the production of biomass-derived compounds.

With the depletion of mineral resources and increasing environmental protection requirements, researching and developing efficient and environmentally friendly flotation agents is crucial for the comprehensive utilization of mineral resources. Low-grade limestone deposits with high impurities pose a challenge for efficient processing and direct industrial applications. This study explores a novel and sustainable approach to address this challenge by evaluating the prospective use of a fatty-acid-rich oilseed residue as a bio-collector (referred to as collector SSFA) to recover carbonates from a low-grade limestone, characterized by high acid insolubles content and its influence on the kinetics of the flotation process. The bio-collector (SSFA) outperformed the conventional collector sodium oleate (referred to as SSO) by significantly increasing the recovery of total carbonates (TC) while simultaneously reducing acid insolubles (AI). A low-grade limestone feed containing 78.40 % TC and 20.90 % AI was upgraded through both mechanical and column flotation techniques. Mechanical flotation yielded a product with 92.9 % TC, 93.48 % TC recovery, 4.0 % AI, and 77.58 % yield at SSFA dosage of 0.87 kg/t. Column flotation, at the same dosage, yielded a product with slightly higher TC content (94.20 %), lower TC recovery (91.02 %), similar AI content (4.07 %), and slightly lower yield (74.68 %). The kinetics of the flotation process indicated that the limestone sample exhibited fast-floating behaviour, attributed to the enhanced selectivity of the SSFA collector. The bio-collector SSFA stands out as a promising and sustainable alternative to conventional collectors for large-scale low-grade limestone flotation due to its remarkable ability to selectively recover total carbonates while minimizing acid insolubles.