The Application Of Solid Acid Catalyst Based On Poms In Bio Energy

With the depletion of fossil fuels, the development of renewable energy has become one of the most important issues in 21st century. With rapid depletion of fossil fuels and the ever-increasing serious environmental problems of global warming, it has become vital to develop efficient renewable energy to replace fossil fuels. Bio energy as a kind of renewable energy is attracting more attention by scientists. Biodiesel,5-HMF and cellulose esters, is a very important part of bio energy, and is usually prepared through the acid catalyzed reaction using biomass as a raw material. Meanwhile, the acid catalyst is a fundamental part of acid catalyzed reaction. Therefore, it is very important to study acid catalyst in acid catalytic reactions in the field of bio energy.In this thesis, we reported a series of catalysts based on the Keggin type polyoxometalates(POMs), and designed a solid acid catalyst of high activity and high selectivity by using polymer as carrier. Aiming to replace the traditional inorganic acids this new type of catalyst is able to produce biodiesel in high efficiency using biomass resources as raw materials. On the other hand, POMs with H2SO4 was used for the preparation of cellulose ester with high viscosity and high molecular weight. In this thesis, various techniques such as FT-IR, BET, TG, HRTEM, TPD and NMR were used. The main results are listed as follows:1. The solid acid catalyst based on Keggin POMs was prepared and the catalytic activity for esterification of fatty acid and dehydration of fructose were studied in detail. The following steps are the preparation procedure: firstly, macroporous polymer with high specific surface area and more active sites was synthesized; secondly, the Keggin POM was mixed with the macroporous polymer and the catalytic performance of the catalyst was investigated. The results demonstrated that these two kinds of reactionsgave more than 98% of the yield.2. The preparation of cellulose acetate propionate. We investigated the properties of cellulose acetate propionate prepared by different catalysts, and chose POMs with H2SO4 as the catalyst to investigate the effect of esterification temperature and time on the product. The catalyst showed high catalytic activity for cellulose acetate propionate, and the advantages of no corrosion and high catalytic stability.To summarize, we has investigated the application of solid acid catalyst based on Keggin POMs in the esterification and dehydration of fructose, and the application of the POMs with H2SO4 in the esterification of cellulose. Preparation and catalytic performance of the catalyst shows that it has a good industrial application potential.