Biofuels Bioproducts & Biorefining-Biofpr最新文献

This research explores the potential for generating biogas and clean energy by processing organic waste, a process that can become a sustainable solution to Syria's energy needs. Focusing on agricultural residues generated from citrus fruit orange, date, and jujube cultivation in Syria, this study evaluates the potential for anaerobic digestion of these residues for biogas production. It highlights the influence of substrate composition and the optimization of fermentation processes on biogas and methane production. The study focuses on evaluating the anaerobic digestion process by examining various dosages ranging from 20% to 50% dry matter for citrus orange waste, and different types of substrate with a fixed ratio of 20% substrate dry matter. It specifically discusses the factors influencing the inhibitory effect of anaerobic digestion, giving particular consideration to orange waste, a significant byproduct of the citrus industry. The biogas produced maintained a stable methane content when a citrus-to-inoculum ratio of 30:70 was used. Jujube waste, characterized by a composition rich in cellulose and hemicellulose, exhibited a higher potential for biogas and methane generation among the fruit waste investigated, particularly when combined with the inoculum in a 20:80 ratio. The research findings underscore the potential of using Syrian agricultural residues, including orange citrus peel, date, and jujube fruit, for the production of biogas through anaerobic digestion.

Existing corn ethanol biorefineries produce about 94% of the ethanol capacity in the USA and currently have surplus production capacity. Expanding feedstocks for existing facilities rather than building new dedicated facilities could provide significant benefits and cost savings. Grain sorghum is a feedstock with a similar composition to corn, which could be utilized at significant incorporation levels in existing facilities with minimal or no modifications but it is currently only used minimally. To understand the impact of grain sorghum incorporation better we studied mixed corn and grain sorghum fermentation at the laboratory scale and utilized the data generated to develop technical models for the individual grains and for a 50/50 mixture at 119 million kg per year (40 million gal per year). Detailed processing and economic comparisons were developed to determine the overall impact. The results showed significant feedstock savings ($8 million per year) potential for utilization of sorghum relative to corn. Ethanol production cost was reduced by $0.07 per kg of ethanol using sorghum relative to corn. Other potential impacts on coproduct composition and values were also determined and discussed.

The cover image is based on the Case Study Sequential extraction of hesperidin, pectin, lignin, and cellulose from orange peels: towards valorization of agro-waste by Symone C. de Castro et al., https://doi.org/10.1002/bbb.2606.

Biomass estimation forms the foundation for tackling global climate issues across diverse land use systems (LUSs). A research initiative was undertaken to identify the maximum biomass allocation using an allometric approach, and to assess the carbon stock, CO₂ sequestration, and carbon credit across diverse land use systems (LUSs) in the Vindhyan region of Mirzapur, Uttar Pradesh, India. This study aims to address climate change by identifying land-use strategies that stabilize income and are easily adoptable by farmers. Tropical dry deciduous forest, agriculture, plantation, horticulture and agri-horticulture LUSs were investigated using three combinations of custard apple (Annona squamosa), guava (Psidium guajava), bael (Aegle marmelos), mustard (Giriraj) (Brassica nigra), mustard (Pitambri) (Brassica juncea), and lentil (Lens culinaris) in an agri-horticulture system. Seven treatments with varying carbon stocks were identified: tropical dry deciduous forest (T₁) LUS (TDDFLUS); wheat based agriculture (T₂) LUS (WBALUS); plantation based on teak (Tectona grandis) (T₃) LUS (TBPLUS); horticulture based on karonda (Carissa carandas) (T₄) LUS (KBHLUS); bael + lentil (Hul-57) (T₅) LUS (BLBLUS); guava + mustard (Giriraj) (T₆) LUS (GMBLUS); and custard apple + mustard (Pitambri) (T₇) LUS (CAMBLUS). The results indicate that the lowest and the highest bulk densities (ρ_b) were recorded in TDDFLUS and WBALUS at the depths of 0–20 cm and 20-40 cm, respectively. The mean value of the soil organic carbon (SOC) stock ranged from 11.24–18.09 t ha⁻¹. The average value of biomass, biomass carbon stock and biomass CO₂ sequestration of seven treatments varied from 9.76–88.49 t ha⁻¹, 4.88–44.25 t ha⁻¹, and 17.91–162.39 t ha⁻¹, respectively. The total carbon stock, CO₂ sequestration, and carbon credit for the seven treatments varied from 16.57–64.64 t ha⁻¹, 60.82–237.28 t ha⁻¹ and 3040.821–11 863.89US$ ha⁻¹, respectively. The results demonstrated that different LUSs have specific advantages and their application at farm level can encourage sustainability and increase biomass accumulation, leading to carbon sequestration. Agri-horticulture-based LUSs can lead to better livelihoods and can also offer numerous advantages such as increased yields of staple food crops and fruits, improved soil health, reduced soil erosion, and significant contributions to the mitigation of anthropogenic warming through CO₂ sequestration.

In this study, the correlation between the composition, hydrogen/carbon (H/C) ratio, and hydrogen/oxygen (H/O) ratio of a used cooking oil (UCO) and the specific emissions embodied in the derived hydroprocessed esters and fatty acids synthetic paraffinic kerosene (HEFA-SPK) is investigated. It is shown that HEFA-SPK produced from UCOs with low concentrations of C18:1, high concentrations of C18:2, and low H/C ratios utilize less energy and more hydrogen during Fuel Production. Hence, HEFA-SPK produced from such UCOs will embody higher gCO₂e for fossil hydrogen utilization scenarios, and lower gCO₂e for green hydrogen utilization scenarios compared with other UCOs. Conversely, it is shown that HEFA-SPK produced from UCOs with high concentrations of C18:1, low concentrations of C18:2 and high H/C ratios utilize more energy and less hydrogen during Fuel Production. Hence, HEFA-SPK derived from such UCOs will embody lower gCO₂e for fossil hydrogen utilization scenarios, and higher gCO₂e for green hydrogen utilization scenarios compared with other UCOs. Monte Carlo simulation gives the emissions embodied in Fuel Production a 95% confidence interval for all UCO-derived HEFA-SPK, showing a similar uncertainty for all compositions. A maximum of +1.1 gCO₂e/MJ_SAF and −1.0 gCO₂e/MJ_SAF is obtained for the upper and lower bounds respectively for the emissions embodied during HEFA-SPK production from UCO. The application of the correlations founded in this study allows for the prediction of the specific emissions embodied in the feedstock-to-fuel conversion of any UCO, providing the C18:1 concentration, C18:2 concentration, H/C ratio and H/O ratio of the UCO is known.

In this work, phosphoric acid pretreatment (0.6% H₃PO₄, 160 °C, 40 min) of eucalyptus residues was performed to recover the hemicellulosic fraction for further conversion to l-lactic acid by fermentation with Weizmannia coagulans DSM 2314 (formerly Bacillus coagulans). The hemicellulosic hydrolysate was composed of xylosaccharides 24.8 g L^–1 (mainly xylose, 20.3 g L^–1), acetic acid 7.8 g L^–1, furfural 0.7 g L^–1, and acid-soluble lignin (ASL) 2.1 g L^–1. It was subsequently purified by using anion exchange or adsorption resins. Different liquor-to-resin ratios were evaluated to obtain a high concentration of xylosaccharides in the eluate and thorough removal of components that inhibit lactic fermentation. The best performance was observed when using Amberlite-XAD-4 resin at a liquor-to-resin ratio of 3:1. An eluted hydrolysate was obtained, preserving 80% of the xylosaccharides and effectively removing almost all furfural, 90% of ASL, and 32% of acetic acid. Subsequently, l-lactic acid production by W. coagulans DSM 2314 was evaluated using concentrated nondetoxified and detoxified hydrolysate obtained with a vacuum oven. For the nondetoxified hydrolysate, 12 g L^–1 of l-lactic acid was obtained after 48 h showing a yield of 0.56 g_{lactic acid} g_sugar^–1 and a xylose consumption of 62%. The detoxification of the liquor significantly improved the fermentation performance of W. coagulans, resulting in a concentration of 16 g L^–1 of lactic acid after 24 h, with a yield of 0.73 g_{lactic acid} g_sugar^–1, and almost complete xylose consumption.

This study explores a novel approach that combines soil recovery with biofuel production, presenting a strategy that addresses the increasing demand for biofuels while sidestepping the food–fuel debate. It also introduces an innovative method for recovering heavy metals from soils through their translocation into the solid product of the conversion process. Phytoremediation trials were conducted under real field conditions, and the thermochemical conversion of the harvested biomass was carried out at lab scale. Field trials took place in 2021–2023 in Lithuania and Serbia. In Serbia, the contamination primarily involved heavy metals, whereas the Lithuanian site was predominantly contaminated with hydrocarbons from petroleum products. The harvested biomass underwent pretreatment and was then used as feedstock for conversion into high-energy carriers. The conversion products were evaluated for their potential to substitute fossil fuels. Finally, the value chain, encompassing key stakeholders and factors impacting the profitability of this approach, was established, and initial estimates were made regarding the size of individual cost components.

This study systematically evaluates fluorine-containing materials with varying compositions of K, Al, Co, Cu, Mg, and Zn as catalysts for glycerol oligomerization. Comprehensive analyses were conducted for all of the catalysts, considering their structural, compositional, morphological characteristics, and basicity, to understand them in greater depth. Among these analyses, gas chromatography was employed to examine the composition of the reaction products. The investigation extended to a recycling study under optimized conditions. Thermogravimetric analysis and X-ray photoelectron spectroscopy were used to characterize the spent catalysts. Catalytic activity was found to be influenced strongly by the fluorine content, demonstrating remarkable performance for the materials containing fluoroperovskites such as KMgF₃ in the catalyst KMgAFC, and K₂ZnF₆ in KZAFC. Remarkably, KZAFC with 20% fluorine exhibited superior glycerol conversion (68%) and selectivity for diglycerol (27%). Comparative analysis with ZnAl-layered double hydroxide highlighted the positive impact of fluorine on catalytic activity. Introducing a calcination step in the catalyst recovery process also demonstrated improved activity during recycling. Interestingly, KZAFC exhibited stability over four reaction cycles, presenting an economic advantage over homogeneous catalysts. The study also shed light on the potential fluorine loss at the surface and potassium leaching into reaction products, correlating these phenomena with the observed decline in activity. These comprehensive findings contribute significantly to advancing sustainable glycerol valorization through heterogeneous catalysis.

The coke deposition on catalysts is a significant problem in the dry reforming of methane at elevated pressures. Understanding and controlling the mechanisms of such deposition is essential in developing a techno-economically viable industrial application for the production of synthesis gas and/or hydrogen. The patent-pending nickel-supported upgraded slag oxide (Ni-UGSO) catalysts, in powder form, have demonstrated excellent performance and achieved equilibrium in dry reforming, steam reforming and mixed methane reforming in a gram-scale laboratory packed bed reactor under barometric pressure. In this extended study, Ni-UGSO pellets were prepared using the wet impregnation method. The pelletized form of said catalyst was studied under elevated pressure to imitate the industrial operating conditions in a kilogram-scale laboratory packed bed reactor. The characterization of the fresh and used catalytic formulation produced data allowing the investigation of the physicochemical properties of catalysts and the effects of metal dispersion, reaction pressure and crystallite size, as well as the role of side reactions on the nature of the coke. The metal support nature favored the interaction between the Ni metal and spinels (UGSO), and the presence of the clay binder (kaolinite, quartz) improved the pellet morphology, provided higher Ni dispersion, maintained the crystallite size, reduced the coke formation and achieved similar or higher performance with respect to Ni-UGSO powder despite having 85% less surface area. The Ni-UGSO pellet showed negligible coke deposits from 1 to 6.5 atm and operated successfully for 24 h at 5.5 atm, 800°C and gas hourly space velocity 810 L/(h kg cat). This study provides new insight into the design of a more efficient and robust catalyst for methane dry reforming at elevated pressures, which is critical for potential future transfer at the industrial level.