Levulinate esters are versatile chemicals that have been used in various fields. Herein, the production of ethyl levulinate（EL） from corn stover was investigated under microwave irradiation. Several reaction paramet...Levulinate esters are versatile chemicals that have been used in various fields. Herein, the production of ethyl levulinate（EL） from corn stover was investigated under microwave irradiation. Several reaction parameters, including acid concentration, reaction temperature, reaction time, and liquid-to-solid mass ratio, were investigated to evaluate the reaction conditions. Response surface methodology（RSM） was employed to optimize the reaction conditions for the production of EL. A quadratic polynomial model was fitted to the data with an R2 value of 0.93. The model validation results reflected a good fit between the experimental and predicted values. A high conversion yield（58.1 mol%） was obtained at the optimum conditions of 190℃, 30.4 min, 2.84 wt% acid, and 15 g/g liquid-to-solid mass ratio. Compared with conventional heating, microwave irradiation facilitated the conversion of corn stover to EL by dramatically shortening the reaction time from several hours to ～30 min. Thus, microwave-assisted conversion of corn stover to EL is an efficient way of utilizing a renewable biomass resource.展开更多
为了探究不同沼液回用方式下玉米秸秆厌氧消化的产气性能及运行稳定性,利用重力筛网过滤沼液和离心过滤沼液,分别对玉米秸秆进行预处理、用作上料配水、同时作预处理和上料配水,进行沼液回用与无沼液回用对比试验。结果表明:过滤沼液对...为了探究不同沼液回用方式下玉米秸秆厌氧消化的产气性能及运行稳定性,利用重力筛网过滤沼液和离心过滤沼液,分别对玉米秸秆进行预处理、用作上料配水、同时作预处理和上料配水,进行沼液回用与无沼液回用对比试验。结果表明:过滤沼液对玉米秸秆厌氧消化性能的提高比离心沼液更加显著,其中用过滤沼液同时作预处理和上料配水的试验组产气效果最佳,总产气量达18 645 m L,完成厌氧消化1个周期内总产气量90%的时间(T_(90))比其他沼液回用试验组提前2~5 d。过滤沼液试验组的物质转化率比离心沼液试验组高。试验组中,消化液的氨氮、碱度等均保持在正常范围,试验系统稳定性良好,沼液回用短时间内不会影响系统的正常运行。展开更多
Bio-fuel can be used to help transition from a petroleum-based society to a bio-based society. Ever since the China Development and Reform Commission suspended the approval of crop processing programs, second-generati...Bio-fuel can be used to help transition from a petroleum-based society to a bio-based society. Ever since the China Development and Reform Commission suspended the approval of crop processing programs, second-generation bio-ethanol research and industrialization processes have attracted significant attention. In 2020, bio-ethanol production is predicted to reach 10 million tons. Currently, there are a few domestic enterprises that have established different scaled pilot or demonstration bases for cellulosic ethanol, which reduce the cost of ethanol by continuously improving pretreatment and hydrolysis techniques. In the next three years, these enterprises will realize large-scale commercial production. Given the practical problems in cellulosic ethanol plant construction and operation(e.g., marketing price variation and difficulties in feedstock collection), this paper began with the concept of a "whole-crop refinery" and presented a solution to the integration of industry and agriculture as well as multi-crop refining. This paper then took the whole-crop refining system of corn as an example and presented an analysis of the logistics, energy flow, and economical efficiency of the system. The results demonstrated that the integrated system could properly reduce the required fixed investments in production equipment,shared utilities, and wastewater treatment facilities, as well as reduction of energy consumption. Although the proposed system has several problems, it brings the long-term goal of large-scale commercial application closer than ever.展开更多
基金financially supported by the National Key R&D Program of China(no.2016YFE0112800)National Natural Science Foundation of China(no.31671572)
文摘Levulinate esters are versatile chemicals that have been used in various fields. Herein, the production of ethyl levulinate（EL） from corn stover was investigated under microwave irradiation. Several reaction parameters, including acid concentration, reaction temperature, reaction time, and liquid-to-solid mass ratio, were investigated to evaluate the reaction conditions. Response surface methodology（RSM） was employed to optimize the reaction conditions for the production of EL. A quadratic polynomial model was fitted to the data with an R2 value of 0.93. The model validation results reflected a good fit between the experimental and predicted values. A high conversion yield（58.1 mol%） was obtained at the optimum conditions of 190℃, 30.4 min, 2.84 wt% acid, and 15 g/g liquid-to-solid mass ratio. Compared with conventional heating, microwave irradiation facilitated the conversion of corn stover to EL by dramatically shortening the reaction time from several hours to ～30 min. Thus, microwave-assisted conversion of corn stover to EL is an efficient way of utilizing a renewable biomass resource.
文摘为了探究不同沼液回用方式下玉米秸秆厌氧消化的产气性能及运行稳定性,利用重力筛网过滤沼液和离心过滤沼液,分别对玉米秸秆进行预处理、用作上料配水、同时作预处理和上料配水,进行沼液回用与无沼液回用对比试验。结果表明:过滤沼液对玉米秸秆厌氧消化性能的提高比离心沼液更加显著,其中用过滤沼液同时作预处理和上料配水的试验组产气效果最佳,总产气量达18 645 m L,完成厌氧消化1个周期内总产气量90%的时间(T_(90))比其他沼液回用试验组提前2~5 d。过滤沼液试验组的物质转化率比离心沼液试验组高。试验组中,消化液的氨氮、碱度等均保持在正常范围,试验系统稳定性良好,沼液回用短时间内不会影响系统的正常运行。
基金Supported by the State Key Development Program for Basic Research of China(2006BAC02A17)
文摘Bio-fuel can be used to help transition from a petroleum-based society to a bio-based society. Ever since the China Development and Reform Commission suspended the approval of crop processing programs, second-generation bio-ethanol research and industrialization processes have attracted significant attention. In 2020, bio-ethanol production is predicted to reach 10 million tons. Currently, there are a few domestic enterprises that have established different scaled pilot or demonstration bases for cellulosic ethanol, which reduce the cost of ethanol by continuously improving pretreatment and hydrolysis techniques. In the next three years, these enterprises will realize large-scale commercial production. Given the practical problems in cellulosic ethanol plant construction and operation(e.g., marketing price variation and difficulties in feedstock collection), this paper began with the concept of a "whole-crop refinery" and presented a solution to the integration of industry and agriculture as well as multi-crop refining. This paper then took the whole-crop refining system of corn as an example and presented an analysis of the logistics, energy flow, and economical efficiency of the system. The results demonstrated that the integrated system could properly reduce the required fixed investments in production equipment,shared utilities, and wastewater treatment facilities, as well as reduction of energy consumption. Although the proposed system has several problems, it brings the long-term goal of large-scale commercial application closer than ever.
