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Research progress on hydrothermal dissolution and hydrolysis of lignocellulose and lignocellulosic waste

Yan ZHAO, Wenjing LU, Jiajun CHEN, Xiangfeng ZHANG, Hongtao WANG

《环境科学与工程前沿(英文)》 2014年 第8卷 第2期   页码 151-161 doi: 10.1007/s11783-013-0607-z

摘要: Ethanol production from lignocellulosic waste has attracted considerable attention because of its feasibility and the generation of valuable products. Previous studies have shown that pretreatment and hydrolysis are key processes for lignocellulose conversion. Hydrothermal process is a promising technique because of its efficiency to break down the lignocellulosic structures and produce fermentable hexoses. Most studies in this field have therefore focused on understanding these processes or optimizing the parameters, but commonly reported low yields of fermentable hexoses. The inability to produce high yields of fermentable hexoses is mainly attributed to inadequate information on the conversion mechanisms of lignocellulose, particularly the reaction rules of dissolution, which is a limiting step in the entire conversion process. This paper critically reviewed the progress done in the research and development of the hydrothermal dissolution and hydrolysis of lignocellulose. Principles, processes, and related studies on separate dissolution and asynchronous hydrolysis of lignin, hemicellulose, and cellulose are presented. Potential research prospects are also suggested.

关键词: lignocellulosic waste     hydrothermal conversion     separate dissolution     asynchronous hydrolysis     mechanism    

Catalytic conversion of biomass-derived compounds to various amino acids: status and perspectives

《化学科学与工程前沿(英文)》 2023年 第17卷 第7期   页码 817-829 doi: 10.1007/s11705-022-2254-z

摘要: Amino acids are important nitrogen-containing chemicals that have a variety of applications. Currently, fermentation is the widely employed method to produce amino acids; however, the products are mostly limited to natural amino acids in the L-configuration. Catalytic synthesis is an alternative approach for the synthesis of amino acids with different types and configurations, where the use of renewable biomass-based feedstocks is highly attractive. To date, several lignocellulose and triacylglycerol-derived intermediates, typically α-keto acids and α-hydroxyl acids, have been transformed into amino acids via the amination reaction in the presence of additional nitrogen sources (i.e., NH3·H2O). Making full use of inherent nitrogen in biomass (i.e., chitin and protein) to produce amino acids avoids the use of extra nitrogen sources and meets the requirements of green chemistry, which is attracting increasing attention. In this review, we summarize different chemical-catalytic systems for the transformation of biomass to amino acids. An outlook on the challenges and opportunities for more effective production of amino acids from biomass by catalytic methods is provided.

关键词: biomass     amino acids     chitin     nitrogen-containing compounds     lignocellulose    

Establishment and verification of a shrinking core model for dilute acid hydrolysis of lignocellulose

Cunwen WANG, Xiaoling DUAN, Weiguo WANG, Zihao LI, Yuanhang QIN

《能源前沿(英文)》 2012年 第6卷 第4期   页码 413-419 doi: 10.1007/s11708-012-0212-z

摘要: The kinetics of lignocellulose hydrolysis under the conditions of high temperature and dilute acid (mass fraction 0.05%) was investigated in this paper. By studying the reducing sugar concentration versus reaction temperature (170°C–220°C) and reaction time (150–1800 s) during the hydrolysis process of five kinds of crop straw (rice, wheat, cotton, rape and corn), the shrinking core model was established, and the differential equation of the model and its analytical solution were obtained. With a numerical calculation method, the kinetic equation was estimated, and the degradation of reducing sugar obeyed first-order kinetics was obtained. The calculated results from the equations agreed well with the original experimental data. The calculation by the model showed that the reducing sugar concentration increases as the size of the particles decrease, and the uniform particles increase.

关键词: lignocellulose     dilute acid hydrolysis     shrinking core model    

Alkali-thermal gasification and hydrogen generation potential of biomass

Alexander B. Koven, Shitang S. Tong, Ramin R. Farnood, Charles Q. Jia

《化学科学与工程前沿(英文)》 2017年 第11卷 第3期   页码 369-378 doi: 10.1007/s11705-017-1662-y

摘要: Generating hydrogen gas from biomass is one approach to lowering dependencies on fossil fuels for energy and chemical feedstock, as well as reducing greenhouse gas emissions. Using both equilibrium simulations and batch experiments with NaOH as a model alkaline, this study established the technical feasibility of converting various biomasses (e.g., glucose, cellulose, xylan and lignin) into H -rich gas via catalyst-free, alkali-thermal gasification at moderate temperatures (as low as 300 °C). This process could produce more H with less carbon-containing gases in the product than other comparable methods. It was shown that alkali-thermal gasification follows , with carbonate being the solid product which is different from the one suggested in the literature. Moreover, the concept of hydrogen generation potential (H -GP)—the maximum amount of H that a biomass can yield, was introduced. For a given biomass C H O , the H -GP would be moles of H . It was demonstrated experimentally that the H -GP was achievable by adjusting the amounts of H O and NaOH, temperature and pressure.

关键词: hydrogen generation potential     biomass     lignocellulose     alkali-thermal gasification     sodium hydroxide    

Ball milling promoted direct liquefaction of lignocellulosic biomass in supercritical ethanol

Chunyan Yang, Xiaoliang Yuan, Xueting Wang, Kejing Wu, Yingying Liu, Changjun Liu, Houfang Lu, Bin Liang

《化学科学与工程前沿(英文)》 2020年 第14卷 第4期   页码 605-613 doi: 10.1007/s11705-019-1841-0

摘要: In the present work, ball milling was applied for the pretreatment of lignocellulose to obtain high conversion and bio-oil yield in supercritical ethanol. Ball milling substantially decreased the crystallinity and particle size of lignocellulose, thereby improving its accessibility in ethanol solvent. An increased bio-oil yield of 59.2% was obtained for the ball milled camphorwood sawdust at 300°C, compared with 39.6% for the original lignocellulose. Decreased crystallinity significantly benefited the conversion of the cellulose component from 60.8% to 91.7%, and decreased particle size was beneficial for the conversion of all components. The obtained bio-oil had a high phenolic content, as analyzed by gas chromatography-mass spectrometry. Methoxylation and retro-aldol condensation were observed during alcoholysis, and the reaction pathways of lignocellulose in supercritical ethanol were attributed to the action of free radicals.

关键词: ball milling     lignocellulose     supercritical ethanol     liquefaction     bio-oil    

标题 作者 时间 类型 操作

Research progress on hydrothermal dissolution and hydrolysis of lignocellulose and lignocellulosic waste

Yan ZHAO, Wenjing LU, Jiajun CHEN, Xiangfeng ZHANG, Hongtao WANG

期刊论文

Catalytic conversion of biomass-derived compounds to various amino acids: status and perspectives

期刊论文

Establishment and verification of a shrinking core model for dilute acid hydrolysis of lignocellulose

Cunwen WANG, Xiaoling DUAN, Weiguo WANG, Zihao LI, Yuanhang QIN

期刊论文

Alkali-thermal gasification and hydrogen generation potential of biomass

Alexander B. Koven, Shitang S. Tong, Ramin R. Farnood, Charles Q. Jia

期刊论文

Ball milling promoted direct liquefaction of lignocellulosic biomass in supercritical ethanol

Chunyan Yang, Xiaoliang Yuan, Xueting Wang, Kejing Wu, Yingying Liu, Changjun Liu, Houfang Lu, Bin Liang

期刊论文