以农林废弃生物质气化合成混合醇工艺为对象,利用混合生命周期评估方法对百吨级系统进行环境影响分析。通过构建系统的工艺模型和收集生命周期资源消耗及排放清单,研究农林业、收储运和制取等各阶段的投入和排放特性,对棉秆、玉米秸秆...以农林废弃生物质气化合成混合醇工艺为对象,利用混合生命周期评估方法对百吨级系统进行环境影响分析。通过构建系统的工艺模型和收集生命周期资源消耗及排放清单,研究农林业、收储运和制取等各阶段的投入和排放特性,对棉秆、玉米秸秆、木屑和枝丫柴4种原料制取系统的环境影响特性进行分析,并与5万吨级系统进行比较。结果表明:百吨级系统生命周期化石能源消耗和温室气体排放分别在589~734 kJ/MJ混合醇和63.2~80.8 g CO_(2)eq/MJ混合醇范围内,制取阶段的电力消耗是最主要的影响因素,其次为系统设备设施投入,玉米秸秆混合醇的环境影响最大,这与原料碳含量低及混合醇收率低有关。展开更多
Efficient conversion of lignin to fine chemicals and biofuel become more and more attractive in biorefinery. In this work, we used a series of silica-alumina catalysts （i.e., SiO2-Al2O3, HY, Hβ, and HZSM-5） to degr...Efficient conversion of lignin to fine chemicals and biofuel become more and more attractive in biorefinery. In this work, we used a series of silica-alumina catalysts （i.e., SiO2-Al2O3, HY, Hβ, and HZSM-5） to degrade lignin into arenes and phenols. The relationship between the catalyst structure and lignin depolymerization performance was investigated. The results showed that both acidity and pore size of the catalyst could influence the conversion of lignin. In the volatilizable product, phenols were identified as the main phenolic monomers via gas chromatography-mass spectrometer. SIO2-Al2O3 was the most efficient catalyst, giving 90.96% degree of conversion, 12.91% yield of phenols, and 2.41% yield of arenes in ethanol at 280℃ for 4 h. The Fourier transform infrared spectroscopy and ^1H nuclear magnetic resonance spectroscopy analysis demonstrated that deoxygenation and alkylation occurred in this process. The effect of solvents was also investigated and the results showed that ethanol was the most efficient solvent.展开更多
文摘以农林废弃生物质气化合成混合醇工艺为对象,利用混合生命周期评估方法对百吨级系统进行环境影响分析。通过构建系统的工艺模型和收集生命周期资源消耗及排放清单,研究农林业、收储运和制取等各阶段的投入和排放特性,对棉秆、玉米秸秆、木屑和枝丫柴4种原料制取系统的环境影响特性进行分析,并与5万吨级系统进行比较。结果表明:百吨级系统生命周期化石能源消耗和温室气体排放分别在589~734 kJ/MJ混合醇和63.2~80.8 g CO_(2)eq/MJ混合醇范围内,制取阶段的电力消耗是最主要的影响因素,其次为系统设备设施投入,玉米秸秆混合醇的环境影响最大,这与原料碳含量低及混合醇收率低有关。
文摘Efficient conversion of lignin to fine chemicals and biofuel become more and more attractive in biorefinery. In this work, we used a series of silica-alumina catalysts （i.e., SiO2-Al2O3, HY, Hβ, and HZSM-5） to degrade lignin into arenes and phenols. The relationship between the catalyst structure and lignin depolymerization performance was investigated. The results showed that both acidity and pore size of the catalyst could influence the conversion of lignin. In the volatilizable product, phenols were identified as the main phenolic monomers via gas chromatography-mass spectrometer. SIO2-Al2O3 was the most efficient catalyst, giving 90.96% degree of conversion, 12.91% yield of phenols, and 2.41% yield of arenes in ethanol at 280℃ for 4 h. The Fourier transform infrared spectroscopy and ^1H nuclear magnetic resonance spectroscopy analysis demonstrated that deoxygenation and alkylation occurred in this process. The effect of solvents was also investigated and the results showed that ethanol was the most efficient solvent.
