【作者】 赵岩；

【导师】 郭庆祥；

【作者基本信息】 中国科学技术大学 ， 可再生洁净能源， 2014， 博士

【摘要】 生物质资源的开发和利用受到世界各国的重视。面对化石能源的逐渐减少,环境问题的日益严重,用生物质资源部分替代目前化石资源势在必行。生物质是一种有机碳构成的植物能源,生物质也是目前唯一一种能够转化制备液体燃料的可再生资源。生物质资源具有可持续性,同时也是一种绿色的资源。生物质来源于植物吸收二氧化碳进行光合作用,因此生物质燃料的使用实现了二氧化碳的零排放,能够有效地缓解地球上由于化石能源使用所带来的日益严重的环境问题。生物质结构复杂,生物质制备的化学品和能源分子的结构具有多样性。以生物质为原料制备大宗化学品和能源分子具有广泛的应用前景。芳烃化合物,特别是苯,甲苯和二甲苯是目前应用非常广泛的大宗化学品,也被称为一级基本有机化工原料。同时芳烃化合物也可以作为汽油添加剂,能够很好的提高汽油辛烷值。因此,基于生物质为原料的芳烃化学品和能源分子的制备是为生物质资源的有效开发利用开辟了一条新的路径,对于生物质的综合利用,以及后续的研究开发都有促进作用。生物质资源的有效利用降低了化石能源在使用过程中对环境和生态带来的破坏,对于改善生态环境具有重要的意义。我们重点发展各种转化方法,实现由生物质到芳烃化合物的转化。主要研究目标是以生物质为原料的芳烃化合物制备。研究的内容包括如何催化转化绿色可再生的生物质资源,如：木质素,生物质平台化合物5-羟甲基糠醛和Y-戊内酯为原料制备芳烃。最终实现以来源于生物质的原料制备苯、甲苯和二甲苯等芳烃化合物。第一章.主要是对生物质的结构,目前生物质的转化应用进行了简要介绍。通过对生物质中水相炼制,包括生物质平台化合物5-羟甲基糠醛和γ-戊内酯的研究进展,木质素的氧化和氢化解聚方法的介绍,以及我们了解的目前生物质化学转化的研究发展历程。热化学转化也是生物质转化的一个重要的方法,我们简述了生物质热解制备生物油,生物油的提质,重点介绍了催化热解在生物质转化中应用。最后,介绍了大宗化学品苯,甲苯和二甲苯的制备和应用,以及目前基于生物质转化为芳烃化合物的研究。第二章.木质素是由大量芳环组成大分子化合物,通过木质素的解聚能够有效地获得芳烃化合物。我们采用催化氧化的方法解聚木质素,通过对温度,溶剂,氧化剂和催化剂的调节,实现木质素的解聚,获得了大量的芳香醛和酸类化合物。第三章.我们采用催化热解的方法解聚木质素获得芳烃化合物。实验发现催化剂的加入具有良好的脱氧效果,在无催化剂条件下获得的主要是酚类(酚类的选择性超过90%)化合物,而催化剂加入后主要获得芳烃化合物(选择性超过87%),特别是甲苯的含量有显著提高。催化热解木质素是有效制备芳环类化合物的方法。第四章.Y-戊内酯作为生物质中纤维素和半纤维素水解后的乙酰丙酸加氢产生的平台化合物,性质相对稳定。但是其与水能够完全的互溶,并且只是C5的含氧化合物,热值较低。因此转化γ-戊内酯到高热值的燃料的研究较多,我们通过催化热解的方法能有效的将Y-戊内酯转化为芳烃化合物。此方法不仅降低了氧含量,同时达到了增长碳链,提高热值的目的。第五章.基于纤维素来源的化合物5-羟甲基糠醛为原料制备芳烃化合物。5-羟甲基糠醛是果糖在酸性条件下脱水获得的平台化合物。但是由于其高含氧量,热值低,稳定性差等缺陷,作为汽油添加剂不合适。将5-羟甲基糠醛有效地转化为芳烃化合物,达到了脱氧,提高热值和稳定性的作用。其中芳烃产物中甲苯的选择性42.7%。第六章.总结与展望。本文的主要工作是以生物质中的木质素,生物质平台化合物5-羟甲基糠醛和γ-戊内酯为原料,通过催化热解的方法制备芳烃化合物。我们成功实现了由生物质到大宗化学品和能源分子芳烃化合物的转化,以比较高的选择性获得苯,甲苯和二甲苯。更多还原

【Abstract】 Lignocellulosic biomass has shown to be an efficient source of carbon for the production of chemicals and fuels, and this renewable resource was attracted national attention. With the depletion of fossil fuels as a source for fuels, chemicals, and energy, growing environmental problems, will require the development of new, sustainable sources for fuels and bulk chemicals. The fraction of energy and chemicals supplied by renewable resources such as biomass can be expected to increase in the foreseeable future. Biomass is the only current sustainable source of organic carbon, and biofuels, fuels derived from plant biomass, is the only current sustainable source of liquid fuels. Biofuels generate significantly less greenhouse gas emissions than do fossil fuels and can even be greenhouse gas neutral if efficient methods for biofuels production are developed.Due to the complexity of biomass structure, the product from biomass was diversity characteristics. Chemicals or energy molecule production from biomass as raw material is a broad prospect. Aromatic hydrocarbons, especially benzene, toluene and xylene are currently widely used in international commodity chemicals. Aromatic hydrocarbons compounds can be used as a gasoline additive and can be very good increase gasoline octane. Therefore, production Aromatic hydrocarbons compounds from biomass as feedstocks has open up a new direction for biomass utilization, and subsequent research has a role in promoting development. Efficient use of biomass resources to reduce the damage of fossil energy in the course of the ecological environment, for the improvement of the ecological environment has important significance.We focus on the development of various conversion methods to achieve aromatic compounds from biomass conversion. The main goal of this paper is based on biomass feedstock for production aromatic compounds. Content of the study including how to catalytic conversion green renewable biomass resources, such as:lignin, biomass platform compound5-(hydroxymethyl) furfural and y-valerolactone as raw aromatics preparation. Our aim is to achieve a transformation of raw materials derived from biomass preparation of bulk chemicals aromatic, as example benzene, toluene and xylene.The First chapter.We introduces biomass structure and converion briefly. The chemical conversion of cellulose to5-Hydroxymethylfurfural and y-Valerolactone were reciewed. We also review of the catalytic lignin valorization literature. Fast pyrolysis is a promising technology for biomass utilization and has much advantage. The product of this technology, known as bio-oil, has lower cost than other bio-fuels. Finally, we describe certain aromatic compounds were introduced bulk chemicals and energy molecule of benzene, toluene and xylene preparation and application, as well as research-based aromatic compounds present biomass conversion process of discovery.The second chapter, Lignin was a large number of benzene linked together to form a three-dimensional structure of macromolecules interwoven through the C-O-C and the C-C bond, it was the obvious candidate to serve as a future aromatic resource for the production of liquid biofuels, biomaterials and green chemicals. In the present study, an efficient catalytic system for lignin oxidation to succinic acid and aromatic compounds were developed.The third chapter, we we reported a promising method for the production of aromatics from pyrolytic lignin. More importantly, phenols are the main products with selectivity over90%at600℃though no catalyst was loaded. For catalytic pyrolysis, selectivity for aromatic hydrocarbons is more than87%. Therefore we have demonstrated the catalytic pyrolysis of lignin is an alternative way to produce fuel additives and useful chemicals.Chapter IV, y-valerolactone can be obtained through the hydrogenation of levulinic acid, which can be obtained from acidic hydrolysis of lignocelluloses biomass. GVL cannot be used as a transportation fuel due to several reasons including high water solubility and lower energy density. This work shows that GVL could be transformed into aromatic hydrocarbons through catalytic pyrolysis. Different zeolite catalysts and reaction conditions have been tested for the catalytic conversion of GVL to aromatic hydrocarbons. By doxygenations or growth of carbon chain length, the fuel energy density of GVL is increased.Chapter V,5-Hydroxymethylfurfural (HMF) was a key intermediate of a biobased chemical industry and production of HMF from biomass. HMF suffered from several limitations for directly used as liquid transportation fuel, such as the high water solubility, easy decomposition and the relatively low energy density compared to petroleum-derived fuels. A novel method for the production of aromatic hydrocarbons from HMF through a single step has been reported in our work. HMF generated aromatic hydrocarbons in42.7%carbon yield through catalytic pyrolysis.Chapter VI, Summary and OutlookIn summary, production aromatic compound throngh catalytic conversion biomass was the major work of this paper. We have been using lignin and biomass compound molecules platform5-Hydroxymethylfurfural and y-valerolactone as raw materials. We have successfully achieved the conversion of biomass to aromatic compounds as commodity chemicals, and high selectivity to obtain benzene, toluene and xylene.更多还原