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Removal of Methylene Blue with hemicellulose/Clay Hybrid Hydrogels

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Chinese Journal of Polymer Science 2016年第6期34卷 709-719页

作者： He-li Cheng Qing-hua Feng Chuan-an Liao Yu Liu Dong-bei Wu 王启刚 Department of Chemistry Tongji University Institute of Pulp and Papermaking Hubei University of Technology Pharmaceutical College Guangxi Medical University Key Laboratory of Pulp and Paper Science & Technology of Ministry of Education of China Qilu University of Technology

In this study, we chose corn stover hemicellulose for the preparation of hydrogels with admirable adsorption properties under mild alkaline conditions. Clay nanosheets were introduced to this system and hemicellulose/clay hybrid hydrogels were prepared. Morphological, mechanical properties and the methylene blue adsorption behaviors of the prepared hydrogels were studied. Results suggested that the addition of clay not only improved the mechanical strength of hemicellulose-based hydrogels, but also increased the adsorption capacity on methylene blue. Moreover, the adsorptions were confirmed to follow pseudo-second order equation for both gels with and without clay. The maximum adsorption capacities on methylene blue for hemicellulose-based hydrogels with or without clay reached 148.8 and 95.6 mg/g, respectively. These results implied that hemicellulose-based hydrogels could be used as promising adsorbents for the removal of methylene blue from waste water.

关键词： hemicellulose Hybrid hydrogel Clay Adsorption.

Identification of Quantitative Trait Loci Affecting hemicellulose Characteristics Based on Cell Wall Composition in a Wild and Cultivated Rice Species

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Molecular Plant 2012年第1期5卷 162-175页

作者： Si-Ju Zhang Xue-Qin Song Bai-Sheng YU Bao-Cai Zhang Chuan-Qing Sun J.Paul Knox Yi-Hua Zhou State Key Laboratory of Plant Genomics Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeiiing 100101China State Key Laboratory of Agro-Biotechnology and Department of Plant Genetics and Breeding China Agricultural UniversityBeijing 100094China Centre for Plant Sciences Faculty of Biological SciencesUniversity of LeedsLeeds LS29JTUK

Cell wall hemicellulosic polysaccharides are structurally complex and diverse. Knowledge about the synthesis of cell wall hemicelluloses and their biological roles is limited. Quantitative trait loci （QTL） mapping is a helpful tool for the dissection of complex phenotypes for gene identification. In this study, we exploited the natural variation in cell wall monosaccharide levels between a common wild rice, Yuanj, and an elite indica cultivar, Teqing, and performed QTL map- ping with their introgression lines （ILs）. Chemical analyses conducted on the culms of Yuanj and TeqJng showed that the major alterations are found in glucose and xylose levels, which are correlated with specific hemicellulosic polymers. Gly- cosidic linkage examination revealed that, in Yuanj, an increase in glucose content results from a higher level of mixed linkage I^-glucan （MLG）, whereas a reduction in xylose content reflects a low level of xylan backbone and a varied arabi- noxylan （AX） structure. Seventeen QTLs for monosaccharides have been identified through composition analysis of the culm residues of 95 core ILs. Four major QTLs affecting xylose and glucose levels are responsible for 19 and 21% of the phenotypic variance, respectively. This study provides a unique resource for the genetic dissection of rice cell wall forma- tion and remodeling in the vegetative organs.

关键词： Quantitative trait loci cell wall composition hemicellulose rice introgression lines wild rice species.

Isolation of hemicellulose from Wood Chips via Extraction with Kraft Green Liquor

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Chemical Research in Chinese Universities 2010年第4期26卷 667-671页

作者： SUN Hui XU Ying-kai XU Guo-zhi Department of Material Science and Engineering China National Center for Quality Supervison ＆ Test of Plastic Products Beo＇ing Technology and Business University Beijing 100048 P. R. China Department of Surgery University of Pittsburg 3459 Fifth Avenue Pittsburgh PA USA

The present paper covers the extraction of hemicelluloses from woods, i.e., Eucalyptus Globulus, white fir and Douglas fir via green liquor pretreatment and alkali post-treatment with sodium hydroxide. The effects of such extraction conditions as extraction time, temperature on the yields of hemicellulose and the degree of deliginification were investigated. Sugar analyses using Dionex indicate that xylose, glucose and mannose are the main sugar types present in the hemicellulose from Eucalyptus. Other sugar components such as arabinose and galactose were also found in Dogulas fir hemicellulose. The highest yield of hemicellulose was 8.4% for Eucalyptus extracted with green liquor at 130 ℃ for 3.5 h. Further sodium hydroxide extraction for 5 h gave a hemicellulose yield of about 20%. The use of green liquor for the extraction of wood hemicellulose is believed to be the first attempt.

关键词： hemicellulose Lignin Wood Green liquor Alkali extraction

Pyrolysis Mechanism of hemicellulose Monosaccharides in Different Catalytic Processes

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Chemical Research in Chinese Universities 2014年第5期30卷 848-854页

作者： WANG Shurong RU Bin LIN Haizhou SUN Wuxing YU Chunjiang LUO Zhongyang State Key Laboratory of Clean Energy Utilization Zhejiang University Hangzhou 310027 P. R. China

The pyrolysis behaviors of four different hemicellulose monosaccharides, namely, two pentoses（xylose and arabinose） and two hexoses（mannose and galactose） catalyzed by HZSM-5 were investigated. The effects of two different processes by which the catalyst comes into contact with the substrate, namely, mixed with monosaccha- ride（in-bed） or layered above monosaccharide（in situ）, were compared. Evolution characteristics of typical pyrolytic products（H20, CO2, acids, furans and aromatics） were achieved by thermogravimetry-Fourier transform infrared spectroscopy. The in-bed catalytic process significantly lowered the pyrolytic temperature and increased the produc- tion of furans and acids at a low temperature by enhancing dehydration, retro-aldol fragmentation and Grob fragmen- tation. During the in situ catalytic process, volatiles generated from monosaccharides passed through a catalyst bed and underwent further dehydration, decarboxylation, and decarbonylation, significantly lowering the yields of acids and furans. The yield of aromatics was enhanced, and the corresponding volatilization temperature was lowered, es- pecially under the in-bed catalytic conditions. Pentoses entered into the zeolite pores more easily than hexoses did because of their smaller molecular size; thus, the in-bed catalytic process drastically affected pentose pyrolysis.

关键词： hemicellulose Monosaccharide TG-FTIR HZSM-5 Pyrolysis

Microwave-Assisted Hydrolysis of hemicellulose over Sulfonated Catalysts

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Advances in Materials Physics and Chemistry 2022年第11期12卷 306-322页

作者： Itidel Belkadhi Mohamed Achraf Bouabdellah Lassâad Ben Hammouda Zouhaier Ksibi Francesco Medina University Tunis-El Manar Tunisia Rovira I Virgili University Tarragona Spain

Sulfonated catalysts based on zirconia (SO3H-ZrO2), silica (SO3H-SBA-15) and zeolite (SO3H-ZSM-5) were studied in the catalytic hydrolysis reaction of hemicellulose in a microwave reactor. The prepared catalysts were characterized by various techniques (XRD, N2 physisorption at 77 K, SEM, TEM and NH3-TPD). The obtained results reveal that despite the differences in their structural and textural properties, the ZrO2, Al-SBA-15 and H-ZSM-5 supports show similar conversions. Doping supports with sulfonate species created hydrogen bonds between SO3H groups and increased the amount of weak acid sites, which enhanced the hydrolysis of hemicellulose. SO3H- ZSM-5 showed the highest catalytic activity followed by SO3H-SBA-15 while SO3H-ZrO2 exhibited a poor conversion. Furthermore, the catalytic hydrolysis of the hemicellulose leads to several interesting products, such as formic acid, acetic acid, lactic acid and xylan. The correlation between the catalytic performances and the acidic properties of the different samples indicates that the best catalytic performances were obtained with the least acidic solids and especially when the density of strong acid sites decreases.

关键词： ZrO2 Al-SBA-15 H-ZSM-5 SO3H hemicellulose Microwave

Green and Effective Ammonium Carbonate-assisted Process for Drying hemicellulose Obtained through Alkali Extraction of Bleached Bamboo Kraft Pulp

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Paper And Biomaterials 2021年第1期6卷 1-10页

作者： Xiaoqi Gong Zongwei Zhang Yonghao Ni Xinhua Ouyang Lihui Chen Liulian Huang Huichao Hu College of Material Engineering Fujian Agriculture and Forestry UniversityFuzhouFujian Province350002China Department of Chemical Engineering University of New BrunswickFrederictonNew BrunswickE3B 5A3Canada

hemicellulose has a wide range of applications,including that as an emulsifier for the food industry and raw material for the synthesis of bioethanol/biochemicals and biodegradable *** is usually present as a spent liquor,such as the prehydrolysis liquor of the prehydrolysis kraft dissolving pulp production process and the alkali extraction liquor of the cold caustic extraction of pulp *** to its dilute nature,hemicellulose needs to be dried for practical utilization,and this is *** this study,cellulose and hemicellulose in a bleached bamboo kraft pulp were separated using an alkali extraction *** obtained from the extraction liquor was dried by an ammonium carbonate-assisted drying *** effects of drying time and drying temperature were *** of the hemicellulose obtained by the ammonium carbonate-assisted drying process was similar to that of original hemicellulose,as revealed by detailed Fourier transform infrared and X-ray diffraction *** novel drying method was more energy efficient and required a shorter drying time than the conventional freeze drying method,and the excellent solubility in alkaline solutions favored the chemical modification of *** dried hemicellulose can be used as a renewable raw material for the preparation of hydrogels and other substances such as bioethanol/biochemicals and biodegradable films.

关键词： bamboo kraft pulp hemicellulose alkali extraction ammonium carbonate drying process dissolving pulp

Extraction,Purification,and Applications of hemicellulose

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Paper And Biomaterials 2021年第3期6卷 47-60页

作者： Mingguo Ma Xingxiang Ji Research Center of Biomass Clean Utilization Engineering Research Center of Forestry Biomass Materials and BioenergyCollege of Materials Science and TechnologyBeijing Forestry UniversityBeijing100083China Key Laboratory of Pulp and Paper Science&Technology of Ministry of Education/Shandong Province Qilu University of Technology(Shandong Academy of Sciences)Ji'nanShandong Province250353China

In addition to cellulose and lignin,hemicellulose is an important biomass ***,hemicellulose and its derivatives and materials have attracted increasing attention owing to their unique structures,improved properties,and promising application potential,and many reports on the extraction,isolation,and modification of hemicellulose are currently *** summarized the recent developments of hemicellulose and its derivatives and materials by focusing on the extraction,purification,and modification of *** synthesis of hemicellulose-based derivatives and materials was also *** methods of extracting,isolating,and modifying hemicellulose were *** challenges related to hemicellulose extraction,purification,and application were mentioned,and directions for further research on hemicellulose were proposed.

关键词： hemicellulose extraction purification modification application

hemicellulose-Based Polymers Processing and Application

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American Journal of Plant Sciences 2020年第12期11卷 2066-2079页

作者： Lisong Hu Xuezhi Fang Menghao Du Fan Luo Shaohai Guo Research Institute of Subtropical Forestry Chinese Academy of Forestry Fuyang China

hemicellulose is the second most abundant biomass in the world. Because of its unique chemical structure, hemicellulose has attracted more and more research and industry application under the background of fossil resource shortage and drawbacks. Hemicellulose is tended to be modified with esterification, etherification, cross-linkage and so on. These reactions change hemicellulose properties, so that it could be applied in many fields such as medical field, films, hydrogels, conductive polymers. Herein, we reviewed structure, isolation, reaction and applications of hemicellulose. Especially the useful pathways to change the hydrophilic character of hemicelluloses to hydrophobic are reviewed and several applications of these materials are discussed.

关键词： hemicellulose Extraction Materials Hydrogel Polymers

hemicellulose-Based Hydrogels Present Status and Application Prospects: A Brief Review

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Open Journal of Forestry 2018年第1期8卷 15-28页

作者： Lisong Hu Menghao Du Jinping Zhang Research Institute of Subtropical Forestry Chinese Academy of Forestry Fuyang China

hemicellulose is one of the most abundant natural resources, which extensively exist in the pant tissues as the compositions of the cell wall filling between lignin and cellulose. In this review, the hemicellulose based hydrogels was illustrated in details including the hemicellulose derivatives (such as precursor of hemicellulose based hydrogel), hydrogels fabrication methods, origin of hemicellulose, composite hydrogels, and so on. In addition, the authors as well overviewed the new methods for fabrication of hemicellulose based hydrogels and special functional hemicellulose based hydrogels.

关键词： hemicellulose Hydrogels Graft polymers Swelling Conductivity