The world's population is growing,leading to an increasing demand for freshwater resources for drinking,sanitation,agriculture,and industry.Interfacial solar steam generation(ISSG)can solve many problems,such as m...The world's population is growing,leading to an increasing demand for freshwater resources for drinking,sanitation,agriculture,and industry.Interfacial solar steam generation(ISSG)can solve many problems,such as mitigating the power crisis,minimizing water pollution,and improving the purification and desalination of seawater,rivers/lakes,and wastewater.Cellulosic materials are a viable and ecologically sound technique for capturing solar energy that is adaptable to a range of applications.This review paper aims to provide an overview of current advancements in the field of cellulose-based materials ISSG devices,specifically focusing on their applications in water purification and desalination.This paper examines the cellulose-based materials ISSG system and evaluates the effectiveness of various cellulosic materials,such as cellulose nanofibers derived from different sources,carbonized wood materials,and two-dimensional(2D)and 3D cellulosic-based materials from various sources,as well as advanced cellulosic materials,including bacterial cellulose and cellulose membranes obtained from agricultural and industrial cellulose wastes.The focus is on exploring the potential applications of these materials in ISSG devices for water desalination,purification,and treatment.The function,advantages,and disadvantages of cellulosic materials in the performance of ISSG devices were also deliberated throughout our discussion.In addition,the potential and suggested methods for enhancing the utilization of cellulose-based materials in the field of ISSG systems for water desalination,purification,and treatment were also emphasized.展开更多
Lignocellulosic biomass is the largest renewable hydrocarbon resource on earth.Converting cellulose,one of the major components of lignocellulose,powered by solar energy is a promising way of providing lowcarbon-footp...Lignocellulosic biomass is the largest renewable hydrocarbon resource on earth.Converting cellulose,one of the major components of lignocellulose,powered by solar energy is a promising way of providing lowcarbon-footprint energy chemicals such as H_(2),HCOOH,CO,and transportation fuels.State-of-the-art biorefineries target the full use of biomass feedstocks as they have a maximum collection radius of 75-100 km,requesting efficient and selective photocatalysts that significantly influence the outcome of photocatalytic biorefineries.Well-performed photocatalysts can harvest a broad solar spectrum and are active in breaking the chemical bonds of cellulose,decreasing the capital investments of biorefineries.Besides,photocatalysts should control the selectivity of cellulose conversion,originating target products to level down separation costs.Charge separation in photocatalysts and interfacial charge transfer between photocatalysts and cellulose affect the activity and selectivity of cellulose refineries to H2 and carbonaceous chemicals.To account for the challenges above,this review summarizes photocatalysts for the refineries of cellulose and downstream platform molecules based on the types of products,with the structure features of different types of photocatalysts discussed in relation to the targets of either improving the activity or product selectivity.In addition,this review also sheds light on the methods for designing and regulating photocatalyst structures to facilitate photocatalytic refineries of cellulose and platform molecules,meanwhile summarizing proposed future research challenges and opportunities for designing efficient photocatalysts.展开更多
This study was conducted to evaluate the effectiveness of enzymes in purifying and reducing the degree of polymerization of cellulose for the production of dissolving pulp.Our goal was to determine the contributions o...This study was conducted to evaluate the effectiveness of enzymes in purifying and reducing the degree of polymerization of cellulose for the production of dissolving pulp.Our goal was to determine the contributions of xylanase(X)and endoglucanase(EG)in the treatment of pulp,specifically by quantifying the formation of soluble and insoluble reducing sugars using the dinitrosalycilic acid(DNS)test.Predominantly,the release of soluble reducing sugars(RSSol)was enhanced after xylanase treatment,while endoglucanase(EG)treatment led to changes in insoluble reducing sugars(RSIns).The maximum synergism was observed for RSIns when a high ratio of endoglucanase to xylanase(320EG:5X/g pulp)was used.The relative contribution of endoglucanase to RSins was determined to be 15.6%of the total reducing sugar.The viscosity of pulps treated with xylanase decreased only by 7%,whereas endoglucanase treatment significantly reduced viscosity by 45%.Modifications in the particle size were observed after pulp treatment with the combination of endoglucanase and xylanase.In summary,the DNS test is a rapid and effective method for evaluating the efficiency of enzyme treatments on pulps.The measurement of RSIns correlates with changes in pulp viscosity to different extents,providing valuable insights into the effectiveness of enzyme treatments.展开更多
Recycling of paper sludge waste is crucial for establishing a sustainable green industry.This waste contains valuable sugars that can be converted into important chemicals such as ethanol,poly hydroxybutyrate,and lact...Recycling of paper sludge waste is crucial for establishing a sustainable green industry.This waste contains valuable sugars that can be converted into important chemicals such as ethanol,poly hydroxybutyrate,and lactic acid.However,the main challenge in obtaining sugars in high yield from paper sludge is the high crystallinity of cellulose,which hinders hydrolysis.To address this,pretreatment using phosphoric acid was optimized using response surface methodology to facilitate cellulose hydrolysis with minimal energy and chemicals.The created prediction model using the response surface method considered factors such as acid concentration(ranging from 60%to 85%),consistency(ranging from 4%to 10%),temperature(ranging from 25℃to 80℃),and time(ranging from 0.5 to 4 h).The results revealed that the model’s significant factors affecting the yield were acid concentration,reaction time,temperature,and the product of acid concentration and temperature,while the model’s significant factors affecting the crystallinity were the consistency,the temperature,and their product.The results showed that the optimum conditions for pretreatment were using an acid concentration of 64%,temperature of 25℃,consistency of 10%,and time of 30 min.The hydrolysis of the conditionally pretreated paper sludge resulted in a weight loss of 42%,compared to only 18%weight loss in non-pretreated paper sludge.Furthermore,the optimized conditions led to low levels of furfurals and acetic acid,which are undesirable by-products that can interfere with sugar fermentation.The total sugar obtained under the optimized conditions was 0.43 g glucose/g sample(10.46 g/L),while the contents of methyl furfural,furfural,and acetic acid were 21.65,235.7,and 4.57 mg/L,respectively.This study demonstrates the potential of phosphoric acid for pretreatment and hydrolysis of paper sludge,enabling efficient saccharification and the production of sugars with minimal undesired by-products.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
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
The conversion of rice hulls into fermentable saccharides was explored through steam pretreatment employing 2.5% SO_(2).The in teraction between temperature and time was assessed by means of the response surface metho...The conversion of rice hulls into fermentable saccharides was explored through steam pretreatment employing 2.5% SO_(2).The in teraction between temperature and time was assessed by means of the response surface method to achieve optimum contents of C6-sugars in water-insoluble solids(WIS)and C5-sugars in the liquor.Pretreatment carried out at 218℃ for 2.3 min released liquor containing 55.4 g/L of sugars(29.1 g/L of xylose).In parallel,the WIS was subjected to enzymatic saccharification using different solid and enzyme loads via an experimental design:assays using 22.0% WIS and 20.0 filter paper units(FPU)/g led to 90.6 g/L of glucose,corresponding to a yield of 86.4% and an overall yield of 72.4%.The data reported are the highest ever found for such raw material,making it attractive to compete with conventi on al lig no cellulosic biomass.展开更多
Mineral fillers are important for conserving raw fiber materials and reducing production costs in the paper industry.However,the increase in filler content will inevitably result in strength reduction,which limits the...Mineral fillers are important for conserving raw fiber materials and reducing production costs in the paper industry.However,the increase in filler content will inevitably result in strength reduction,which limits the adding amount of filler in paper production.In this study,we designed a cellulose fiber/filler co-refining approach to improve the strength and optical properties of paper;moreover,the synergistic interaction between fibers and precipitated calcium carbonate(PCC)fillers in the co-refining process was investigated.Results of fiber separation and PCC particle size analysis showed that,compared with conventional refining,the content of fines increased,whereas the PCC particle size decreased.More importantly,composites were formed between the PCC and fines,which promoted strength improvement of paper.Physical tests show that the tensile index of paper with 15%PCC content increased by 22%compared with that of the paper filled by conventional method,whereas the brightness and opacity of paper improved by fiber/filler co-refining for a specified filler content.These findings provide a basis for the further development of co-refining filling technology.展开更多
This paper focuses on the study of the physical, biochemical, structural, and thermal properties of plant fibres of <i>Rhecktophyllum camerunense</i> (RC), <i>Neuropeltis acuminatas</i> (NA) an...This paper focuses on the study of the physical, biochemical, structural, and thermal properties of plant fibres of <i>Rhecktophyllum camerunense</i> (RC), <i>Neuropeltis acuminatas</i> (NA) and <i>Ananas</i> <i>comosus</i> (AC) from the equatorial region of Cameroon. The traditional use of these fibres inspired researchers to investigated their properties. This study aims at improving the state of knowledge with a view to diversifying applications. The fibres are extracted by retting. Then, their apparent density was measured following the ASTM D792 standard and their water moisture absorption and moisture content were also evaluated. Their molecular structure was studied by ATR-FTIR spectroscopy. A quantitative analysis of the biochemical composition was performed according to the analytical technique for the pulp and paper industry (TAPPI). A TGA/DSC analysis was also performed. The results reveal that the AC, NA and RC fibres have densities of 1.26 ± 1.06, 0.846 ± 0.13 and 0.757 ± 0.08 g·cm<sup>-3</sup> respectively. They are also hydrophilic with a water absorption rate of 188.64 ± 11.94%, 276.16% ± 8.07% and 198.17% ± 20%. They have a moisture content of 12.21%, 10.36% and 9.37%. The studied fibres exhibit functional groups that are related to the presence of hemicellulose, pectin, lignin and cellulose. The cellulose crystallinity index was found to be 67.99%, 46.5% and 59.72% respectively. The fibres under study have the following chemical composition: an extractive content of 3.07%, 14.77% and 8.74%;a pectin content of 4.15%, 7.69% and 3.45%;a hemicellulose content of 4.90%, 15.33% and 7.42%;a cellulose content of 68.11%, 36.08% and 65.15%;a lignin content of 12.01%, 25.15% and 16.2%;and an ash content of 0.27%, 1.53% and 0.47% respectively. The thermal transitions observed on the thermograms correlate with the TAPPI chemical composition. It is observed that these fibres are thermally stable up to temperatures of 200°C, 220°C and 285°C. These results make it possible to envisage uses similar to those of sisal, hemp and flax fibres.展开更多
The Far East population of Miscanthus sinensis (Andersson) was introduced into the West Siberia conditions. There was distinguished a form with a modified structure of the rootage which forms long shoots with leader b...The Far East population of Miscanthus sinensis (Andersson) was introduced into the West Siberia conditions. There was distinguished a form with a modified structure of the rootage which forms long shoots with leader buds and rapidly colonizes soil, thus forming a continuous and flat (without tussocks) plantation of miscanthus. It is shown that using usual agrotechnologies, it is possible to obtain 10-15 tons of dry biomass of high quality cellulose (about 40%) per ha/year.展开更多
Titanium dioxide nanoparticle was synthesized by the reduction of titanium tetrachloride using borohydride, water as solvent, and polyvinyl-pyrrolidone as stabilizer. The average size of nano-TiO2 is estimated to be 5...Titanium dioxide nanoparticle was synthesized by the reduction of titanium tetrachloride using borohydride, water as solvent, and polyvinyl-pyrrolidone as stabilizer. The average size of nano-TiO2 is estimated to be 5 - 10 nm using a transmission electron microscope (TEM);this was confirmed by X-ray diffraction and UV-Vis spectroscopy. Nano-TiO2 was impregnated into cotton fabric to impart multifunctional properties and this was confirmed by scanning electron microscope and scanning electron microscope coupled with high energy distribution X-Ray (SEM-EDX). The TiO2 nanoparticles loaded cotton fabrics showed excellent antibacterial activity against two representative bacteria, Staphylococcus aureus (Gram positive) 96.6% and Klebsiella pneumonia (Gram negative) 95.2%. Also, TiO2 nanoparticles enhanced the self-cleaning and the protection of cotton fabrics against UV radiation in comparison with the untreated cotton fabrics. The TiO2 nanoparticles were durable in-situ cotton fabrics even after 20 laundering wash cycles.展开更多
Cellulosic ethanol involves the following production steps: physical and/or chemical pretreatment, biological treatment, fermentation and distillation. First three steps are also the bottlenecks for the production of ...Cellulosic ethanol involves the following production steps: physical and/or chemical pretreatment, biological treatment, fermentation and distillation. First three steps are also the bottlenecks for the production of cellulosic ethanol and its co-products. Their production still pose some difficulties in terms of pretreatment, the high cost of enzymes for substrate hydrolysis, the formation of inhibitory compounds in the hydrolyzate, the lack of efficient and viable microorganisms for industrial fermentation of hexose and pentose among others. The solution or minimization of these difficulties may lead to numerous socio-environmental, political, and economic advantages for cellulosic ethanol production. This paper highlights the potential of different substrates, pretreatments, microorganisms and bioprocesses for cellulosic ethanol production.展开更多
Waste cellulosic biomass obtains various applications due to low-cost and eco-benign characteristics.A general strategy is proposed for waste cellulosic biomass to be modified with dialdehyde functional groups as inte...Waste cellulosic biomass obtains various applications due to low-cost and eco-benign characteristics.A general strategy is proposed for waste cellulosic biomass to be modified with dialdehyde functional groups as intermediates through periodate partial oxidation.Finally,aminothiourea-modified waste cellulosic biomass can be prepared through Schiff reaction.Waste corn stalk,cotton and paper as typical precursors,were used to prepare cellulosic biomass,abbreviated as AT-S,AT-C and AT-P,respectively,and their adsorption behaviors of Au(III)from the hydrochloric acid medium were investigated.The pseudo-second kinetics equation as well as the Langmuir isotherm equation can be used to depict the adsorption process,and the maximum adsorption capacities of Au(III)are21.4,19.0and3.28mol/kg for AT-S,AT-C and AT-P at298K,respectively.The adsorption capacities of Au(III)on aminothiourea modified corn stalk(AT-S)is almost357times greater than that of raw corn stalk.To the best of our knowledge,AT-S has the highest adsorption capacity towards Au(III).AT-S also displays a superior separation selectivity towards Au(III)in the presence of Cu(II),Ni(II),Co(II),Pt(VI),Pd(II)and Rh(III).Furthermore,the characterization analysis of XRD,TG,SEM,TEM and FTIR confirms that AuCl4– has been reduced to elemental Au nanoparticles and deposit onto the surface of the biomass.It shows a prospect for waste corn stalk to be used to adsorb Au(III)from liquid phase and the possible fabrication of gold nanoparticles by a general adsorption process without any reductant.展开更多
In this paper, the rapid liquefaction of a corncob was achieved by plasma electrolysis, providing a new method for cellulosic biomass liquefaction. The liquefaction rate of the corncob was 95% after 5 min with polyeth...In this paper, the rapid liquefaction of a corncob was achieved by plasma electrolysis, providing a new method for cellulosic biomass liquefaction. The liquefaction rate of the corncob was 95% after 5 min with polyethylene glycol and glycerol as the liquefying agent. The experiments not only showed that H~+ ions catalyzed the liquefaction of the corncob, but also that using accelerated H~+ ions, which were accelerated by an electric field, could effectively improve the liquefaction efficiency. There was an obvious discharge phenomenon, in which the generated radicals efficiently heated the solution and liquefied the biomass, in the process of plasma electrolytic liquefaction. Finally, the optimum parameters of the corncob liquefaction were obtained by experimentation, and the liquefaction products were analyzed.展开更多
Instead of finishing the fabrics with inorganic particles by a binder, in this study the fine aluminium oxide powder were added during the polymerization system of a monomer with functional hydroxyl groups HPMA. The h...Instead of finishing the fabrics with inorganic particles by a binder, in this study the fine aluminium oxide powder were added during the polymerization system of a monomer with functional hydroxyl groups HPMA. The hot alkaline testing showed that the Al<sub>2</sub>O<sub>3</sub> particles had reacted with the polymer latex. The absorbability and wash durability of the fabric treated with such a latex with Al<sub>2</sub>O<sub>3</sub> were measured.展开更多
Cationic modifying agent ( PECH- amine) with lower molecular weight and containing less nitrogen was prepared and characterized. The water-soluble cationic modification agent has high reactivity for cotton. Cotton mod...Cationic modifying agent ( PECH- amine) with lower molecular weight and containing less nitrogen was prepared and characterized. The water-soluble cationic modification agent has high reactivity for cotton. Cotton modified by this agent can be dyed under salt-free and neutral conditions with direct and reactive dyes. Dyes in the dyebath could be completely exhausted and a dyeing effluent without residual dyes and salt could be expected.展开更多
Wastewater from the production of cellulosic ethanol was treated by the processes of internal micro-electrolysis method +ABR+UASB +MBR. The results of running indicated that, when COD is 12000 mg/L and HRT of UASB ...Wastewater from the production of cellulosic ethanol was treated by the processes of internal micro-electrolysis method +ABR+UASB +MBR. The results of running indicated that, when COD is 12000 mg/L and HRT of UASB is 48 h, the COD removal rate reaches 72% and HRT of MBR is 20 h, COD removal rate is between 80.8% and 87.5%. The effluent COD concentration stabilized at 301- 537 mg/L, it indicates that the MBR system has a strong ability to resist impact load.展开更多
In concert with governmental policy for promoting the use of biofuels, the Institute of Nuclear Energy Research (INER) is dedicated to the research and development of technologies for cellulosic ethanol production. ...In concert with governmental policy for promoting the use of biofuels, the Institute of Nuclear Energy Research (INER) is dedicated to the research and development of technologies for cellulosic ethanol production. A pilot plant for cellulosic ethanol production with a capacity of one ton in dry biomass per day was established in 2007 and launched test-run operations for mass production in early 2010. The feedstock is focused on rice straw currently, but is also flexible for sugarcane bagasse and hardwood. The operative experiences and the experimental data will provide valuable information for the evaluation of production cost as well as the foundation for design of a commercial production plant in Taiwan. Additionally, this pilot plant will also serve as an important platform for validation of technologies related to cellulosic ethanol production and biorefinery operations. The biomass-to-ethanol process of this plant is based on the route of biochemical conversions. Developed and developing technologies, such as acid hydrolysis pretreatment, high solid to liquid ratio hydrolysis, in-house cellulase production, xylose fermentation, and the distillation and dehydration processes will be introduced.展开更多
Biorefineries are keen to design optimal biomass supply chains to minimize production, harvest, transport, and other costs. Such a design problem is challenging with the availability of multiple feedstocks (agricultur...Biorefineries are keen to design optimal biomass supply chains to minimize production, harvest, transport, and other costs. Such a design problem is challenging with the availability of multiple feedstocks (agricultural residues, perennials such as energy crops, short rotation woody crops), sourced from multiple harvest sheds, and transported across multiple modes (trucks, rails, and barges). This paper presents a multi-period optimization model to analyze the feasibility of collection from multiple harvest sheds. The results are demonstrated for a case study location in Alpena, MI served by truck and water transport. The model results suggest that: i) perennial biomass with higher yields would be preferred due to higher biomass production per unit area;ii) transport from farther locations are warranted only if the biomass production costs in the farther harvest sheds are cheaper by 20% - 30% compared to the adjacent harvest shed;and iii) the local situations of a biorefinery—characterized by the parametric inputs in the model—play a key role in determining the optimal feedstock composition across multiple harvest sheds. The results also support long term contracts associated with high yielding perennial feedstocks such as energy crops and short rotation woody crops.展开更多
Competitive absorption processes, i.e. condensation, of water and essential oils (EO) are predominantly controlled by extent of condensation of diffusing water and EO molecules with marginal influence of porose ligno-...Competitive absorption processes, i.e. condensation, of water and essential oils (EO) are predominantly controlled by extent of condensation of diffusing water and EO molecules with marginal influence of porose ligno-cellulosic matter and a sort of EO. With increase of absorption the diffusion is depressed and vice versa. Diffusion of water molecules through porose system is usually slower in comparison with other molecules. It was discovered that a presence of EO decreases paper web humidity with increasing influence in environment with high relative air humidity. Likely, fast diffusing EO molecules decrease the ability of water molecules condensed in all accessible pores particularly in the non-penetrable pores.展开更多
基金This study was supported by Key Research and Development Program of Hubei Province(No.2022ACA002).
文摘The world's population is growing,leading to an increasing demand for freshwater resources for drinking,sanitation,agriculture,and industry.Interfacial solar steam generation(ISSG)can solve many problems,such as mitigating the power crisis,minimizing water pollution,and improving the purification and desalination of seawater,rivers/lakes,and wastewater.Cellulosic materials are a viable and ecologically sound technique for capturing solar energy that is adaptable to a range of applications.This review paper aims to provide an overview of current advancements in the field of cellulose-based materials ISSG devices,specifically focusing on their applications in water purification and desalination.This paper examines the cellulose-based materials ISSG system and evaluates the effectiveness of various cellulosic materials,such as cellulose nanofibers derived from different sources,carbonized wood materials,and two-dimensional(2D)and 3D cellulosic-based materials from various sources,as well as advanced cellulosic materials,including bacterial cellulose and cellulose membranes obtained from agricultural and industrial cellulose wastes.The focus is on exploring the potential applications of these materials in ISSG devices for water desalination,purification,and treatment.The function,advantages,and disadvantages of cellulosic materials in the performance of ISSG devices were also deliberated throughout our discussion.In addition,the potential and suggested methods for enhancing the utilization of cellulose-based materials in the field of ISSG systems for water desalination,purification,and treatment were also emphasized.
基金supported by the National Natural Science Foundation of China(22172157,22025206)the Dalian Innovation Support Plan for High Level Talents(2022RG13),DICP(DICP I202116)+1 种基金the Youth Innovation Promotion Association(YIPA)of the Chinese Academy of Sciences(2023192)the Fundamental Research Funds for the Central Universities(20720220008)。
文摘Lignocellulosic biomass is the largest renewable hydrocarbon resource on earth.Converting cellulose,one of the major components of lignocellulose,powered by solar energy is a promising way of providing lowcarbon-footprint energy chemicals such as H_(2),HCOOH,CO,and transportation fuels.State-of-the-art biorefineries target the full use of biomass feedstocks as they have a maximum collection radius of 75-100 km,requesting efficient and selective photocatalysts that significantly influence the outcome of photocatalytic biorefineries.Well-performed photocatalysts can harvest a broad solar spectrum and are active in breaking the chemical bonds of cellulose,decreasing the capital investments of biorefineries.Besides,photocatalysts should control the selectivity of cellulose conversion,originating target products to level down separation costs.Charge separation in photocatalysts and interfacial charge transfer between photocatalysts and cellulose affect the activity and selectivity of cellulose refineries to H2 and carbonaceous chemicals.To account for the challenges above,this review summarizes photocatalysts for the refineries of cellulose and downstream platform molecules based on the types of products,with the structure features of different types of photocatalysts discussed in relation to the targets of either improving the activity or product selectivity.In addition,this review also sheds light on the methods for designing and regulating photocatalyst structures to facilitate photocatalytic refineries of cellulose and platform molecules,meanwhile summarizing proposed future research challenges and opportunities for designing efficient photocatalysts.
基金supported by CNPq(303416/2018-1)and FAPESP(2019/25867-3).
文摘This study was conducted to evaluate the effectiveness of enzymes in purifying and reducing the degree of polymerization of cellulose for the production of dissolving pulp.Our goal was to determine the contributions of xylanase(X)and endoglucanase(EG)in the treatment of pulp,specifically by quantifying the formation of soluble and insoluble reducing sugars using the dinitrosalycilic acid(DNS)test.Predominantly,the release of soluble reducing sugars(RSSol)was enhanced after xylanase treatment,while endoglucanase(EG)treatment led to changes in insoluble reducing sugars(RSIns).The maximum synergism was observed for RSIns when a high ratio of endoglucanase to xylanase(320EG:5X/g pulp)was used.The relative contribution of endoglucanase to RSins was determined to be 15.6%of the total reducing sugar.The viscosity of pulps treated with xylanase decreased only by 7%,whereas endoglucanase treatment significantly reduced viscosity by 45%.Modifications in the particle size were observed after pulp treatment with the combination of endoglucanase and xylanase.In summary,the DNS test is a rapid and effective method for evaluating the efficiency of enzyme treatments on pulps.The measurement of RSIns correlates with changes in pulp viscosity to different extents,providing valuable insights into the effectiveness of enzyme treatments.
文摘Recycling of paper sludge waste is crucial for establishing a sustainable green industry.This waste contains valuable sugars that can be converted into important chemicals such as ethanol,poly hydroxybutyrate,and lactic acid.However,the main challenge in obtaining sugars in high yield from paper sludge is the high crystallinity of cellulose,which hinders hydrolysis.To address this,pretreatment using phosphoric acid was optimized using response surface methodology to facilitate cellulose hydrolysis with minimal energy and chemicals.The created prediction model using the response surface method considered factors such as acid concentration(ranging from 60%to 85%),consistency(ranging from 4%to 10%),temperature(ranging from 25℃to 80℃),and time(ranging from 0.5 to 4 h).The results revealed that the model’s significant factors affecting the yield were acid concentration,reaction time,temperature,and the product of acid concentration and temperature,while the model’s significant factors affecting the crystallinity were the consistency,the temperature,and their product.The results showed that the optimum conditions for pretreatment were using an acid concentration of 64%,temperature of 25℃,consistency of 10%,and time of 30 min.The hydrolysis of the conditionally pretreated paper sludge resulted in a weight loss of 42%,compared to only 18%weight loss in non-pretreated paper sludge.Furthermore,the optimized conditions led to low levels of furfurals and acetic acid,which are undesirable by-products that can interfere with sugar fermentation.The total sugar obtained under the optimized conditions was 0.43 g glucose/g sample(10.46 g/L),while the contents of methyl furfural,furfural,and acetic acid were 21.65,235.7,and 4.57 mg/L,respectively.This study demonstrates the potential of phosphoric acid for pretreatment and hydrolysis of paper sludge,enabling efficient saccharification and the production of sugars with minimal undesired by-products.
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.
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 Coordination for the Improvement of Higher Education Personnel Foundation,Mmistry of Education in Brazil(Grant No.POS-DOC-88881.170076/2018-01).
文摘The conversion of rice hulls into fermentable saccharides was explored through steam pretreatment employing 2.5% SO_(2).The in teraction between temperature and time was assessed by means of the response surface method to achieve optimum contents of C6-sugars in water-insoluble solids(WIS)and C5-sugars in the liquor.Pretreatment carried out at 218℃ for 2.3 min released liquor containing 55.4 g/L of sugars(29.1 g/L of xylose).In parallel,the WIS was subjected to enzymatic saccharification using different solid and enzyme loads via an experimental design:assays using 22.0% WIS and 20.0 filter paper units(FPU)/g led to 90.6 g/L of glucose,corresponding to a yield of 86.4% and an overall yield of 72.4%.The data reported are the highest ever found for such raw material,making it attractive to compete with conventi on al lig no cellulosic biomass.
基金This work was financially supported by Innovation Capability Support Program of Shaanxi(2020KJXX082)the Foundation(202005)of Tianjin Key Laboratory of Pulp&Paper(Tianjin University of Science&Technology).
文摘Mineral fillers are important for conserving raw fiber materials and reducing production costs in the paper industry.However,the increase in filler content will inevitably result in strength reduction,which limits the adding amount of filler in paper production.In this study,we designed a cellulose fiber/filler co-refining approach to improve the strength and optical properties of paper;moreover,the synergistic interaction between fibers and precipitated calcium carbonate(PCC)fillers in the co-refining process was investigated.Results of fiber separation and PCC particle size analysis showed that,compared with conventional refining,the content of fines increased,whereas the PCC particle size decreased.More importantly,composites were formed between the PCC and fines,which promoted strength improvement of paper.Physical tests show that the tensile index of paper with 15%PCC content increased by 22%compared with that of the paper filled by conventional method,whereas the brightness and opacity of paper improved by fiber/filler co-refining for a specified filler content.These findings provide a basis for the further development of co-refining filling technology.
文摘This paper focuses on the study of the physical, biochemical, structural, and thermal properties of plant fibres of <i>Rhecktophyllum camerunense</i> (RC), <i>Neuropeltis acuminatas</i> (NA) and <i>Ananas</i> <i>comosus</i> (AC) from the equatorial region of Cameroon. The traditional use of these fibres inspired researchers to investigated their properties. This study aims at improving the state of knowledge with a view to diversifying applications. The fibres are extracted by retting. Then, their apparent density was measured following the ASTM D792 standard and their water moisture absorption and moisture content were also evaluated. Their molecular structure was studied by ATR-FTIR spectroscopy. A quantitative analysis of the biochemical composition was performed according to the analytical technique for the pulp and paper industry (TAPPI). A TGA/DSC analysis was also performed. The results reveal that the AC, NA and RC fibres have densities of 1.26 ± 1.06, 0.846 ± 0.13 and 0.757 ± 0.08 g·cm<sup>-3</sup> respectively. They are also hydrophilic with a water absorption rate of 188.64 ± 11.94%, 276.16% ± 8.07% and 198.17% ± 20%. They have a moisture content of 12.21%, 10.36% and 9.37%. The studied fibres exhibit functional groups that are related to the presence of hemicellulose, pectin, lignin and cellulose. The cellulose crystallinity index was found to be 67.99%, 46.5% and 59.72% respectively. The fibres under study have the following chemical composition: an extractive content of 3.07%, 14.77% and 8.74%;a pectin content of 4.15%, 7.69% and 3.45%;a hemicellulose content of 4.90%, 15.33% and 7.42%;a cellulose content of 68.11%, 36.08% and 65.15%;a lignin content of 12.01%, 25.15% and 16.2%;and an ash content of 0.27%, 1.53% and 0.47% respectively. The thermal transitions observed on the thermograms correlate with the TAPPI chemical composition. It is observed that these fibres are thermally stable up to temperatures of 200°C, 220°C and 285°C. These results make it possible to envisage uses similar to those of sisal, hemp and flax fibres.
文摘The Far East population of Miscanthus sinensis (Andersson) was introduced into the West Siberia conditions. There was distinguished a form with a modified structure of the rootage which forms long shoots with leader buds and rapidly colonizes soil, thus forming a continuous and flat (without tussocks) plantation of miscanthus. It is shown that using usual agrotechnologies, it is possible to obtain 10-15 tons of dry biomass of high quality cellulose (about 40%) per ha/year.
文摘Titanium dioxide nanoparticle was synthesized by the reduction of titanium tetrachloride using borohydride, water as solvent, and polyvinyl-pyrrolidone as stabilizer. The average size of nano-TiO2 is estimated to be 5 - 10 nm using a transmission electron microscope (TEM);this was confirmed by X-ray diffraction and UV-Vis spectroscopy. Nano-TiO2 was impregnated into cotton fabric to impart multifunctional properties and this was confirmed by scanning electron microscope and scanning electron microscope coupled with high energy distribution X-Ray (SEM-EDX). The TiO2 nanoparticles loaded cotton fabrics showed excellent antibacterial activity against two representative bacteria, Staphylococcus aureus (Gram positive) 96.6% and Klebsiella pneumonia (Gram negative) 95.2%. Also, TiO2 nanoparticles enhanced the self-cleaning and the protection of cotton fabrics against UV radiation in comparison with the untreated cotton fabrics. The TiO2 nanoparticles were durable in-situ cotton fabrics even after 20 laundering wash cycles.
基金the Brazilian research funding agencies CNPq and FUNDECT for their financial support.
文摘Cellulosic ethanol involves the following production steps: physical and/or chemical pretreatment, biological treatment, fermentation and distillation. First three steps are also the bottlenecks for the production of cellulosic ethanol and its co-products. Their production still pose some difficulties in terms of pretreatment, the high cost of enzymes for substrate hydrolysis, the formation of inhibitory compounds in the hydrolyzate, the lack of efficient and viable microorganisms for industrial fermentation of hexose and pentose among others. The solution or minimization of these difficulties may lead to numerous socio-environmental, political, and economic advantages for cellulosic ethanol production. This paper highlights the potential of different substrates, pretreatments, microorganisms and bioprocesses for cellulosic ethanol production.
基金Projects(51504073,51404081,51672275)supported by the National Natural Science Foundation of ChinaProject(2012CBA01202)supported by the National Key Technology Research and Development Program of the Ministry of Science and Technology,China+1 种基金Project(QianJiaoKeHe KY[2015]433)supported by the Research Program of the Education Department of Guizhou Province,ChinaProject(XJG20141104)supported by the Research Program of Talented Scholars of Guizhou Institute of Technology,China
文摘Waste cellulosic biomass obtains various applications due to low-cost and eco-benign characteristics.A general strategy is proposed for waste cellulosic biomass to be modified with dialdehyde functional groups as intermediates through periodate partial oxidation.Finally,aminothiourea-modified waste cellulosic biomass can be prepared through Schiff reaction.Waste corn stalk,cotton and paper as typical precursors,were used to prepare cellulosic biomass,abbreviated as AT-S,AT-C and AT-P,respectively,and their adsorption behaviors of Au(III)from the hydrochloric acid medium were investigated.The pseudo-second kinetics equation as well as the Langmuir isotherm equation can be used to depict the adsorption process,and the maximum adsorption capacities of Au(III)are21.4,19.0and3.28mol/kg for AT-S,AT-C and AT-P at298K,respectively.The adsorption capacities of Au(III)on aminothiourea modified corn stalk(AT-S)is almost357times greater than that of raw corn stalk.To the best of our knowledge,AT-S has the highest adsorption capacity towards Au(III).AT-S also displays a superior separation selectivity towards Au(III)in the presence of Cu(II),Ni(II),Co(II),Pt(VI),Pd(II)and Rh(III).Furthermore,the characterization analysis of XRD,TG,SEM,TEM and FTIR confirms that AuCl4– has been reduced to elemental Au nanoparticles and deposit onto the surface of the biomass.It shows a prospect for waste corn stalk to be used to adsorb Au(III)from liquid phase and the possible fabrication of gold nanoparticles by a general adsorption process without any reductant.
基金supported by the Natural Science Foundation of Guangdong Province, China (Grant No. 2015A030313005)the opening foundation (Grant No. 2016002) of Key Laboratory of Advanced Textile Materials and Manufacturing Technology (Zhejiang SciTech University)+2 种基金Fundamental Research Funds for the Central Universities, China (Grant No. 20720150022)Ministry of Educationthe Fund from the Fujian Provincial Key Laboratory for Plasma and Magnetic Resonance, China
文摘In this paper, the rapid liquefaction of a corncob was achieved by plasma electrolysis, providing a new method for cellulosic biomass liquefaction. The liquefaction rate of the corncob was 95% after 5 min with polyethylene glycol and glycerol as the liquefying agent. The experiments not only showed that H~+ ions catalyzed the liquefaction of the corncob, but also that using accelerated H~+ ions, which were accelerated by an electric field, could effectively improve the liquefaction efficiency. There was an obvious discharge phenomenon, in which the generated radicals efficiently heated the solution and liquefied the biomass, in the process of plasma electrolytic liquefaction. Finally, the optimum parameters of the corncob liquefaction were obtained by experimentation, and the liquefaction products were analyzed.
文摘Instead of finishing the fabrics with inorganic particles by a binder, in this study the fine aluminium oxide powder were added during the polymerization system of a monomer with functional hydroxyl groups HPMA. The hot alkaline testing showed that the Al<sub>2</sub>O<sub>3</sub> particles had reacted with the polymer latex. The absorbability and wash durability of the fabric treated with such a latex with Al<sub>2</sub>O<sub>3</sub> were measured.
文摘Cationic modifying agent ( PECH- amine) with lower molecular weight and containing less nitrogen was prepared and characterized. The water-soluble cationic modification agent has high reactivity for cotton. Cotton modified by this agent can be dyed under salt-free and neutral conditions with direct and reactive dyes. Dyes in the dyebath could be completely exhausted and a dyeing effluent without residual dyes and salt could be expected.
文摘Wastewater from the production of cellulosic ethanol was treated by the processes of internal micro-electrolysis method +ABR+UASB +MBR. The results of running indicated that, when COD is 12000 mg/L and HRT of UASB is 48 h, the COD removal rate reaches 72% and HRT of MBR is 20 h, COD removal rate is between 80.8% and 87.5%. The effluent COD concentration stabilized at 301- 537 mg/L, it indicates that the MBR system has a strong ability to resist impact load.
文摘In concert with governmental policy for promoting the use of biofuels, the Institute of Nuclear Energy Research (INER) is dedicated to the research and development of technologies for cellulosic ethanol production. A pilot plant for cellulosic ethanol production with a capacity of one ton in dry biomass per day was established in 2007 and launched test-run operations for mass production in early 2010. The feedstock is focused on rice straw currently, but is also flexible for sugarcane bagasse and hardwood. The operative experiences and the experimental data will provide valuable information for the evaluation of production cost as well as the foundation for design of a commercial production plant in Taiwan. Additionally, this pilot plant will also serve as an important platform for validation of technologies related to cellulosic ethanol production and biorefinery operations. The biomass-to-ethanol process of this plant is based on the route of biochemical conversions. Developed and developing technologies, such as acid hydrolysis pretreatment, high solid to liquid ratio hydrolysis, in-house cellulase production, xylose fermentation, and the distillation and dehydration processes will be introduced.
文摘Biorefineries are keen to design optimal biomass supply chains to minimize production, harvest, transport, and other costs. Such a design problem is challenging with the availability of multiple feedstocks (agricultural residues, perennials such as energy crops, short rotation woody crops), sourced from multiple harvest sheds, and transported across multiple modes (trucks, rails, and barges). This paper presents a multi-period optimization model to analyze the feasibility of collection from multiple harvest sheds. The results are demonstrated for a case study location in Alpena, MI served by truck and water transport. The model results suggest that: i) perennial biomass with higher yields would be preferred due to higher biomass production per unit area;ii) transport from farther locations are warranted only if the biomass production costs in the farther harvest sheds are cheaper by 20% - 30% compared to the adjacent harvest shed;and iii) the local situations of a biorefinery—characterized by the parametric inputs in the model—play a key role in determining the optimal feedstock composition across multiple harvest sheds. The results also support long term contracts associated with high yielding perennial feedstocks such as energy crops and short rotation woody crops.
基金supported by the Ministry of Culture of the Czech Republic under the Research Projects NAKI DF11P01OVV028.
文摘Competitive absorption processes, i.e. condensation, of water and essential oils (EO) are predominantly controlled by extent of condensation of diffusing water and EO molecules with marginal influence of porose ligno-cellulosic matter and a sort of EO. With increase of absorption the diffusion is depressed and vice versa. Diffusion of water molecules through porose system is usually slower in comparison with other molecules. It was discovered that a presence of EO decreases paper web humidity with increasing influence in environment with high relative air humidity. Likely, fast diffusing EO molecules decrease the ability of water molecules condensed in all accessible pores particularly in the non-penetrable pores.