共查询到20条相似文献,搜索用时 765 毫秒
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本论文研究了以减四线油为原料,通过糠醛精制工艺及加氢精制工艺生产环保橡胶油,探讨了工艺条件对产品性质的影响,并对两种工艺的优缺点进行了比较。研究结果表明,通过糠醛抽提工艺及加氢精制工艺均可得到CA值12%左右的环保橡胶油,但加氢精制工艺的收率高达97%以上,比糠醛抽提工艺的收率高10%以上。 相似文献
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高温稀酸催化玉米芯水解生产糠醛工艺优化 总被引:5,自引:0,他引:5
针对我国糠醛行业现存的资源利用率低的问题,采用高温稀酸催化玉米芯水解生产糠醛,利用平流泵连续向高压釜中通水,通过单因素和正交实验优化糠醛生产工艺.研究了停留时间、硫酸浓度、温度、硫酸浓度和温度的交互作用及液固比对糠醛收率的影响.结果表明,在实验范围内各因素对糠醛收率的影响次序为:停留时间温度液固比硫酸浓度.综合考虑糠醛收率和耗水量,确定的适宜工艺条件为:停留时间100min,温度180℃,硫酸浓度0.5%,液固质量比8:1.在此优化条件下,糠醛收率达75.27%,比国内现有玉米芯生产糠醛工业过程提高了15%~20%. 相似文献
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糠醛是一种应用广泛的化工原料,其现有生产工艺在产率、能耗及环境污染等方面存在较大问题。本文介绍了现有的主流生产工艺如Quaker Oats工艺,Agrifuran工艺,Petrole-chimie工艺,Escher Wyss工艺及Rosenlew工艺存在的不足,分析了半纤维素生成糠醛的机理及水解动力学研究、糠醛生产设备的更新改造。从溶剂体系、催化剂体系、分离方法、加热方式等多方面探讨发展新的糠醛生产工艺。提出今后的研究重点要放在开发绿色的溶剂及催化剂上,以期对生态环境的危害降至最低。 相似文献
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Furfural, which is one of the most promising platform chemicals derived from biomass, has the potential for the production of biofuels and biochemicals. However, the current industrial furfural production process relies on relatively old and inefficient technology, which has some problems such as low production yields, environmental pollutions, and lack of biomass comprehensive utilization. The main contribution of this paper is the use of a modified Scheibel column to improve the furfural recovery. Integration of pentose dehydration to furfural and the solvent phase extraction of furfural occurred simultaneously in this column. Compared with the prevailing batch biphasic reactor, the use of this modified column intensified the extraction efficiency as well as the furfural recovery. Process parameters including organic feed flow rate, reaction temperature, and stirring speed were evaluated and turned out to be significant. In order to achieve the optimal operating conditions, the CCD design was used to optimize the process parameters, and the maximum furfural yield of 80.5% was obtained. 相似文献
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Integrated furfural production as a renewable fuel and chemical platform from lignocellulosic biomass 下载免费PDF全文
Charles M Cai Taiying Zhang Rajeev Kumar Charles E Wyman 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2014,89(1):2-10
Furfural is a natural precursor to furan‐based chemicals and has the potential to become a major renewable platform chemical for the production of biochemicals and biofuels. However, current industrial furfural production relies on relatively old and inefficient strategies that have hindered its capacity, and low production yields have strongly diminished its competitiveness with petroleum‐based alternatives in the global market. This mini‐review provides a critical analysis of past and current progress to enhance furfural production from lignocellulosic biomass. First, important chemical and fuel products derived from the catalytic conversion of furfural are outlined. We then discuss the importance of developing integrated production strategies to co‐produce furfural with other valuable chemicals. Furfural formation and loss chemistries are explored to understand effective methods to improve furfural yields from pentosans. Finally, selected relevant commercial and academic technologies that promise to improve lignocellulosic furfural production are discussed. © 2013 Society of Chemical Industry 相似文献
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Durlubh K. Sharma Prakash N. Sahgal 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1982,32(6):666-668
Agricultural wastes such as rice husks and sawdust can be used for the manufacture of chemicals including furfural and acetic acid. In the present work the conventional use of superheated steam has been replaced by the use of superheated water in the acidic hydrolysis of rice husk and sawdust. Comparable yields of furfural have been obtained by using superheated water in place of superheated steam in the same temperature and pressure range. This is an attempt to economise the heat requirement and reduce the cost of production of furfural. 相似文献
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糠醛是由可再生的生物质为原料转化得到的高价值化工产品,具有广阔的应用前景。本文综述了近年来生物质催化水解制备糠醛的研究进展,同时总结了糠醛衍生产品的制备和应用。在对半纤维素水解产糖反应和木糖脱水反应进行机理分析的基础上,从反应原料、溶剂体系、催化剂和分离方法等方面归纳总结了生物质催化水解制备糠醛的最新研究进展,并提出当前生物质制备糠醛方法中存在的问题和应对方案。在此基础上,分析了糠醛经氢化、胺化、氧化、缩醛化、聚合等反应获得高价值衍生产品的研究进展。提出要实现糠醛绿色高效的生产和应用,应着力设计低成本、低能耗、低污染且高效率的催化反应体系,同时推进重要糠醛衍生产品的综合高效利用。 相似文献
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Ananda S. Amarasekara 《Israel journal of chemistry》2019,59(9):789-802
The ionic liquids have emerged as new solvents and catalysts for processing biomass to value added chemicals and fuels. This review will present the recent developments in applications of ionic liquids in lignocellulosic biomass pretreatments, depolymerization, biodiesel synthesis, dehydration of carbohydrates to renewable feedstock chemicals as well as further transformations of biomass derived feedstocks such as furfural, 5‐hydroxymethylfurfural and levulinic acid to value added chemicals. In addition, the recycling of ionic liquids used in biomass processing is also discussed in the review. 相似文献
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生物基糠醛制备戊二醇的工艺相比于传统的石油基路线,具有原料来源广泛、生产过程绿色无污染等优点。本文总结了国内外以生物基糠醛为原料制备戊二醇的研究现状,并对应用于糠醛催化加氢制备戊二醇的铑、铱、铂、铜基催化剂分别进行了归纳整理,同时详细论述了两种糠醛氢解路线,即糠醛加氢分别以糠醇和四氢糠醇为中间体而氢解生成戊二醇的过程。在此基础上,提出了解决目前糠醛氢解制备戊二醇过程中存在的反应物浓度低、活性差、反应压力高等问题的建议。对未来从经济、环保等多角度出发设计并完善生物基戊二醇的生产工艺以及拓展高效利用生物基糠醛制备下游精细化工产品的方法做出了展望。为开发在温和条件下高效、稳定的催化生物基糠醛氢解的催化剂体系提供了参考。 相似文献
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A recent strong trend toward green and sustainable chemistry has promoted the intensive use of renewable carbon sources for the production of polymers, biofuels, chemicals, monomers and other valuable products. The Diels-Alder reaction is of great importance in the chemistry of renewable resources and provides an atom-economic pathway for fine chemical synthesis and for the production of materials. The biobased furans furfural and 5-(hydroxymethyl)furfural, which can be easily obtained from the carbohydrate part of plant biomass, were recognized as “platform chemicals” that will help to replace the existing oil-based refining to biorefining. Diels-Alder cycloaddition of furanic dienes with various dienophiles represents the ideal example of a “green” process characterized by a 100% atom economy and a reasonable E-factor. In this review, we first summarize the literature data on the regio- and diastereoselectivity of intermolecular Diels-Alder reactions of furfural derivatives with alkenes with the aim of establishing the current progress in the efficient production of practically important low-molecular-weight products. The information provided here will be useful and relevant to scientists in many fields, including medical and pharmaceutical research, polymer development and materials science. 相似文献
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液态烷烃C5+是汽油、柴油、航空燃油等当前社会的运输燃料的主要成分。本文综述了利用木质纤维素衍生平台化学品制备液体燃料的研究进展,着重总结了生物质衍生平台化学品通过碳链增长得到长链含氧化合物,然后经过加氢脱氧(HDO)得到C7+液体烷烃的技术研究进展。木质纤维素衍生平台化学品包括山梨醇、糠醛、5-羟甲基糠醛(HMF)、环戊酮、甲基呋喃、酚类、丙酮、丁醇、乙醇、乙酰丙酸、γ-戊内酯等。其中,糠醛、5-羟甲基糠醛和环戊酮在碱性催化剂作用下能与其他羰基化合物发生羟醛缩合反应实现碳链增长;甲基呋喃、苯类及苯酚类衍生物可以在强酸催化作用下通过烷基化/羟烷基化反应实现碳链增长;丙酮能与乙醇、丁醇发生α-烷基化反应实现碳链增长;乙酰丙酸可以转化为戊酸、丁烯或当归内酯,再分别通过酮基化反应、烯烃齐聚反应和加成反应实现碳链增长。诸多利用生物质衍生物化学品制备长链烷烃的路径中,利用5-羟甲基糠醛和甲基呋喃制备长链烷烃的技术路线存在路径过长、原料不易获取的问题;利用环戊酮和苯酚类物质能够得到高密度长链环烷烃,是一条有竞争力的路线;糠醛和乙酰丙酸易于从生物质中大规模制取,且利用糠醛和乙酰丙酸制备长链烷烃的反应路径短,较易实现工业应用。 相似文献