Interactions of lignocellulosic components during fiber analysis were investigated using the highly adopted compositional analysis procedure from the National Renewable Energy Laboratory(NREL),USA.Synthetic feedstoc...Interactions of lignocellulosic components during fiber analysis were investigated using the highly adopted compositional analysis procedure from the National Renewable Energy Laboratory(NREL),USA.Synthetic feedstock samples were used to study the effects of lignin/protein,cellulose/protein,and xylan/protein interaction on carbohydrate analysis.Disregarding structural influence in the synthetic samples,lignin and protein components were the most significant(P〈0.05)factors on cellulose analysis.Measured xylan was consistent and unaffected by content variation throughout the synthetic analysis.Validation of the observed relationships from synthetic feedstocks was fulfilled using real lignocellulosic feedstocks:corn stover,poplar,and alfalfa,in which similar results have been obtained,excluding cellulose analysis of poplar under higher protein content and xylan analysis of alfalfa under higher protein content.The results elucidated that according to their protein and lignin contents of different lignocellulosic materials,accuracy of the NREL method on cellulose and xylan analyses could be improved by applying a stronger extraction step to replace water/ethanol extraction.展开更多
Lignocellulosic biomass has attracted great interest in recent years for energy production due to its renewability and carbon-neutral nature.There are various ways to convert lignocellulose to gaseous,liquid and solid...Lignocellulosic biomass has attracted great interest in recent years for energy production due to its renewability and carbon-neutral nature.There are various ways to convert lignocellulose to gaseous,liquid and solid fuels via thermochemical,chemical or biological approaches.Typical biomass derived fuels include syngas,bio-gas,bio-oil,bioethanol and biochar,all of which could be used as fuels for furnace,engine,turbine or fuel cells.Direct biomass fuel cells mediated by various electron carriers provide a new direction of lignocellulose conversion.Various metal and non-metal based carriers have been screened for mediating the electron transfer from biomass to oxygen thus generating electricity.The power density of direct biomass fuel cells can be over 100 mW cm^(-2),which shows promise for practical applications.Lignocellulose and its isolated components,primarily cellulose and lignin,have also been paid considerable attention as sustainable carbonaceous materials for preparation of electrodes for supercapacitors,lithium-ion batteries and lithium-sulfur batteries.In this paper,we have provided a state-of-the-art review on the research progress of lignocellulosic biomass as feedstock and materials for power generation and energy storage focusing on the chemistry aspects of the processes.It was recommended that process integration should be performed to reduce the cost for thermochemical and biological conversion of lignocellulose to biofuels,while efforts should be made to increase efficiency and improve the properties for biomass fuelled fuel cells and biomass derived electrodes for energy storage.展开更多
Bioconversion of lignocellulosic biomass to ethanol is significantly hindered by the structural and chemical complexity of biomass,which makes these materials a challenge to be used as feedstocks for cellulosic ethano...Bioconversion of lignocellulosic biomass to ethanol is significantly hindered by the structural and chemical complexity of biomass,which makes these materials a challenge to be used as feedstocks for cellulosic ethanol production.Cellulose and hemicellulose,when hydrolyzed into their component sugars,can be converted into ethanol through well established fermentation technologies.However,sugars necessary for fermentation are trapped inside the crosslinking structure of the lignocellulose.Hence,pretreatment of biomass is always necessary to remove and/or modify the surrounding matrix of lignin and hemicellulose prior to the enzymatic hydrolysis of the polysaccharides(cellulose and hemicellulose)in the biomass.Pretreatment refers to a process that converts lignocellulosic biomass from its native form,in which it is recalcitrant to cellulase enzyme systems,into a form for which cellulose hydrolysis is much more effective.In general,pretreatment methods can be classified into three categories,including physical,chemical,and biological pretreatment.The subject of this paper emphasizes the biomass pretreatment in preparation for enzymatic hydrolysis and microbial fermentation for cellulosic ethanol production.It primarily covers the impact of biomass structural and compositional features on the pretreatment,the characteristics of different pretreatment methods,the pretreatment study status,challenges,and future research targets.展开更多
基金supported by the Michigan Public Service Commission (PSC-09-19),USAthe Michigan Animal Agriculture Initiative, the Michigan State Agricultural Station, Michigan State University (MSU) Ag Bio Researchthe MSU Vice President for Research and Graduate Studies,USA
文摘Interactions of lignocellulosic components during fiber analysis were investigated using the highly adopted compositional analysis procedure from the National Renewable Energy Laboratory(NREL),USA.Synthetic feedstock samples were used to study the effects of lignin/protein,cellulose/protein,and xylan/protein interaction on carbohydrate analysis.Disregarding structural influence in the synthetic samples,lignin and protein components were the most significant(P〈0.05)factors on cellulose analysis.Measured xylan was consistent and unaffected by content variation throughout the synthetic analysis.Validation of the observed relationships from synthetic feedstocks was fulfilled using real lignocellulosic feedstocks:corn stover,poplar,and alfalfa,in which similar results have been obtained,excluding cellulose analysis of poplar under higher protein content and xylan analysis of alfalfa under higher protein content.The results elucidated that according to their protein and lignin contents of different lignocellulosic materials,accuracy of the NREL method on cellulose and xylan analyses could be improved by applying a stronger extraction step to replace water/ethanol extraction.
基金supported by the National Natural Science Foundation of China(No.21878176)National Key Research and Development Program of China(No.2018YFA0902200)financially supported by the Imperial College President’s PhD Scholarship Scheme。
文摘Lignocellulosic biomass has attracted great interest in recent years for energy production due to its renewability and carbon-neutral nature.There are various ways to convert lignocellulose to gaseous,liquid and solid fuels via thermochemical,chemical or biological approaches.Typical biomass derived fuels include syngas,bio-gas,bio-oil,bioethanol and biochar,all of which could be used as fuels for furnace,engine,turbine or fuel cells.Direct biomass fuel cells mediated by various electron carriers provide a new direction of lignocellulose conversion.Various metal and non-metal based carriers have been screened for mediating the electron transfer from biomass to oxygen thus generating electricity.The power density of direct biomass fuel cells can be over 100 mW cm^(-2),which shows promise for practical applications.Lignocellulose and its isolated components,primarily cellulose and lignin,have also been paid considerable attention as sustainable carbonaceous materials for preparation of electrodes for supercapacitors,lithium-ion batteries and lithium-sulfur batteries.In this paper,we have provided a state-of-the-art review on the research progress of lignocellulosic biomass as feedstock and materials for power generation and energy storage focusing on the chemistry aspects of the processes.It was recommended that process integration should be performed to reduce the cost for thermochemical and biological conversion of lignocellulose to biofuels,while efforts should be made to increase efficiency and improve the properties for biomass fuelled fuel cells and biomass derived electrodes for energy storage.
文摘Bioconversion of lignocellulosic biomass to ethanol is significantly hindered by the structural and chemical complexity of biomass,which makes these materials a challenge to be used as feedstocks for cellulosic ethanol production.Cellulose and hemicellulose,when hydrolyzed into their component sugars,can be converted into ethanol through well established fermentation technologies.However,sugars necessary for fermentation are trapped inside the crosslinking structure of the lignocellulose.Hence,pretreatment of biomass is always necessary to remove and/or modify the surrounding matrix of lignin and hemicellulose prior to the enzymatic hydrolysis of the polysaccharides(cellulose and hemicellulose)in the biomass.Pretreatment refers to a process that converts lignocellulosic biomass from its native form,in which it is recalcitrant to cellulase enzyme systems,into a form for which cellulose hydrolysis is much more effective.In general,pretreatment methods can be classified into three categories,including physical,chemical,and biological pretreatment.The subject of this paper emphasizes the biomass pretreatment in preparation for enzymatic hydrolysis and microbial fermentation for cellulosic ethanol production.It primarily covers the impact of biomass structural and compositional features on the pretreatment,the characteristics of different pretreatment methods,the pretreatment study status,challenges,and future research targets.