In the present study,the hydrolysates generated via autohydrolysis of spruce wood chips were di-rectly used as feedstock for producing coagulants.The in-situ polymerization of acrylamide(AM)and lignocellulose(LC)of hy...In the present study,the hydrolysates generated via autohydrolysis of spruce wood chips were di-rectly used as feedstock for producing coagulants.The in-situ polymerization of acrylamide(AM)and lignocellulose(LC)of hydrolysates was successfully conducted.The reaction was optimized to generate lignocellulose-acrylamide(LC-AM)with the highest molecular weight(41,060 g/mol)and charge density(-0.25 meq/g)under the optimum conditions,which were 3 h,60◦C,4%(w)initiator based on the dried mass of hydrolysate,and an AM/LC molar ratio of 5.63.A nuclear magnetic resonance(NMR)spectroscopy confirmed the grafting of acrylamide on LC.Other prop-erties of LC-AM were characterized by the elemental analyzer,zeta potential analyzer,gel per-meation chromatography(GPC),and particle charge detector(PCD).The LC-AM was applied as a coagulant for removing ethyl violet dye from a simulated dye solution.The results indicated that 47.2%dye was removed from the solution at a low dosage of 0.2 g/g.The dual flocculation of LC-AM with other polymers for dye removal is suggested to further improve its effectiveness.展开更多
Current large scale biomass energy production systems including cellulosic ethanol,gasification,and pyrolysis facilities face significant technical and economic hurdles.Compared with these large scale systems,small di...Current large scale biomass energy production systems including cellulosic ethanol,gasification,and pyrolysis facilities face significant technical and economic hurdles.Compared with these large scale systems,small distributed biomass energy production systems(DBEPS)are believed to offer advantages including lower capital costs,lower feedstock costs,simplified transportation and logistics and higher returns for biomass producers.DBEPS compliant technologies are expected to make utilization of regional biomass supplies practical and economically viable in the near-term.This paper presents arguments on the need and importance of DBEPS,available DBEPS options,and an economic scenario of DBEPS implementation on an average size farm in the US.展开更多
When considering the current state of the biorefinery industry, it is readily apparent that industrial cellulose and hemicellulose digestion processes are relatively advanced, whereas enzymatic pre-treatment strategie...When considering the current state of the biorefinery industry, it is readily apparent that industrial cellulose and hemicellulose digestion processes are relatively advanced, whereas enzymatic pre-treatment strategies for biomass delignification and cellulose solubilization are not well developed. The need for efficient biomass pre-treatment strategies presents a significant opportunity for researchers studying lignocellulose digestion in termites and other insects. With an emphasis on industrial biomass pre-treatment, this review provides an overview of: (i) industrial biorefining operations (feedstocks, processing, and economics); (ii) recent findings from termite research that have revealed candidate enzymes; and (iii) research needs and opportunities for consideration by entomologists working in this area. With respect to research findings, recently identified candidate lignases (laccases, catalases, peroxidases, esterases), other potentially important detoxification enzymes (cytochrome P450, superoxide dismutase), and phenolic acid esterases (carboxylesterases) that may assist in hemicellulose solubilization are overviewed. Regarding research needs and opportunities, several approaches for identification of candidate pre-treatment enzymes from upstream, symbiont-free gut regions are also described.展开更多
Surface active agents(surfactants)are chemicals that can accumulate at the surface of a liquid,or interface between two phases with the role of changing the surface tension of the interface.Depending on their structur...Surface active agents(surfactants)are chemicals that can accumulate at the surface of a liquid,or interface between two phases with the role of changing the surface tension of the interface.Depending on their structures,they have many applications in industries,such as the petroleum,mining,pulping and textiles,wherein they are utilized as detergents,wetting agents,emulsifiers,foaming agents and dispersants.Most of commonly used surfactants are oil-based chemicals.However,using environmentally friendly feedstocks to produce surfactant is desirable to lessen the environmental impact of surfactant production and use in industry.Lignin is an attractive candidate for this purpose as it is inexpensive and readily available.Lignin and lignin derivatives,such as lignosulfonates,can be chemically modified to produce surfactants with different chemical and physical properties,which makes them suitable for a wide variety of applications.The lignin types and the processes performed for lignin production affect the properties of generated lignin significantly,which in turn influence the reactivity and the efficiency of the reaction for surfactant generation.In this review,the characteristics and applications of oil-based surfactants,and the efforts to produce lignin-based surfactants are reviewed.As oil-based surfactants with altered properties are available in the market,several different pathways can be followed for producing lignin-based surfactants.The advantages and disadvantages of using lignin-based surfactants are also discussed.展开更多
文摘In the present study,the hydrolysates generated via autohydrolysis of spruce wood chips were di-rectly used as feedstock for producing coagulants.The in-situ polymerization of acrylamide(AM)and lignocellulose(LC)of hydrolysates was successfully conducted.The reaction was optimized to generate lignocellulose-acrylamide(LC-AM)with the highest molecular weight(41,060 g/mol)and charge density(-0.25 meq/g)under the optimum conditions,which were 3 h,60◦C,4%(w)initiator based on the dried mass of hydrolysate,and an AM/LC molar ratio of 5.63.A nuclear magnetic resonance(NMR)spectroscopy confirmed the grafting of acrylamide on LC.Other prop-erties of LC-AM were characterized by the elemental analyzer,zeta potential analyzer,gel per-meation chromatography(GPC),and particle charge detector(PCD).The LC-AM was applied as a coagulant for removing ethyl violet dye from a simulated dye solution.The results indicated that 47.2%dye was removed from the solution at a low dosage of 0.2 g/g.The dual flocculation of LC-AM with other polymers for dye removal is suggested to further improve its effectiveness.
文摘Current large scale biomass energy production systems including cellulosic ethanol,gasification,and pyrolysis facilities face significant technical and economic hurdles.Compared with these large scale systems,small distributed biomass energy production systems(DBEPS)are believed to offer advantages including lower capital costs,lower feedstock costs,simplified transportation and logistics and higher returns for biomass producers.DBEPS compliant technologies are expected to make utilization of regional biomass supplies practical and economically viable in the near-term.This paper presents arguments on the need and importance of DBEPS,available DBEPS options,and an economic scenario of DBEPS implementation on an average size farm in the US.
文摘When considering the current state of the biorefinery industry, it is readily apparent that industrial cellulose and hemicellulose digestion processes are relatively advanced, whereas enzymatic pre-treatment strategies for biomass delignification and cellulose solubilization are not well developed. The need for efficient biomass pre-treatment strategies presents a significant opportunity for researchers studying lignocellulose digestion in termites and other insects. With an emphasis on industrial biomass pre-treatment, this review provides an overview of: (i) industrial biorefining operations (feedstocks, processing, and economics); (ii) recent findings from termite research that have revealed candidate enzymes; and (iii) research needs and opportunities for consideration by entomologists working in this area. With respect to research findings, recently identified candidate lignases (laccases, catalases, peroxidases, esterases), other potentially important detoxification enzymes (cytochrome P450, superoxide dismutase), and phenolic acid esterases (carboxylesterases) that may assist in hemicellulose solubilization are overviewed. Regarding research needs and opportunities, several approaches for identification of candidate pre-treatment enzymes from upstream, symbiont-free gut regions are also described.
文摘Surface active agents(surfactants)are chemicals that can accumulate at the surface of a liquid,or interface between two phases with the role of changing the surface tension of the interface.Depending on their structures,they have many applications in industries,such as the petroleum,mining,pulping and textiles,wherein they are utilized as detergents,wetting agents,emulsifiers,foaming agents and dispersants.Most of commonly used surfactants are oil-based chemicals.However,using environmentally friendly feedstocks to produce surfactant is desirable to lessen the environmental impact of surfactant production and use in industry.Lignin is an attractive candidate for this purpose as it is inexpensive and readily available.Lignin and lignin derivatives,such as lignosulfonates,can be chemically modified to produce surfactants with different chemical and physical properties,which makes them suitable for a wide variety of applications.The lignin types and the processes performed for lignin production affect the properties of generated lignin significantly,which in turn influence the reactivity and the efficiency of the reaction for surfactant generation.In this review,the characteristics and applications of oil-based surfactants,and the efforts to produce lignin-based surfactants are reviewed.As oil-based surfactants with altered properties are available in the market,several different pathways can be followed for producing lignin-based surfactants.The advantages and disadvantages of using lignin-based surfactants are also discussed.