Furfural Catalyzed Process Study Of The Legal System Tetrahydrofuran

Furfural is a kind of chemical material obtained from plants, which is cheap, very active. THF is widely used in industry both as a kind of important raw material for organic synthesis and good solvent. Along with the rapid development of applied chemistry and fine chemical industry, the requirement of THF is increasing continuously. Our country need ten thousand tons of THF each year, which is mainly imported, and the price is becoming higher and higher. That means it is urgent to find the optimal producing technique. At present, THF is mainly produced from petroleum. But with the problem of international petroleum crisis becoming increasingly serious, the prospect of this route is unoptimistic. Using furfural, which is obtained from plants, to produce THF is a fine way to avoid the problem of petroleum shortage and also satisfy people's demands of the green chemical industry. Jilin Province is rich in the cron and has lots of factories producing furfural. Therefore, the research of preparing THF from furfural by catalysis has great significance.The experiment is related to the technical process of preparing THF by furfural catalysis process. This process includes two steps, they are decarbonylation of furfural, hydrogenation of furan.For the first step, a series of Pd/γ-Al2O3 catalysts were Prepared by impregnation, and their catalytic performances for the furfural decarbonylation into funan were evaluated in the fixed-bed reactor. It was found that the 0.4%Pd/γ-Al2O3 catalyst prepared by impregnating and then precipitating was optimum. Furfural conversion rate was more than 98%,and the selectivity to funan was over 96% under the conditions of 0.08MPa,300℃and hydrogen venting 20ml/min.Results of the catalyst measure by BET,XRD,CO2-TPD indicated that palladium particles were dispersed well, and palladium catalyst had a larger surface area, and the pore size and shape of the catalyst distribute uniform.Catalysts appeared a weak alkaline.The second step is funan hydrogenation test. The research is focused on the best process conditions of furan hydrogenation by Pd/C catalyst。This study considered the impact of various factors, Designed orthogonal test. By orthogonal test, the amount of catalyst is the biggest factor affecting test, and the various hydrogenation factors is identified by the single factor test.Optimum conditions for hydrogenation process is as follows:In the reaction,temperature is 140℃, reaction pressure is 3MPa, the amount of catalyst for the furan is 4%(mass ratio), add 1%(volume ratio) of triethylamine additive and ethanol as a solvent under the conditions, conversion rate is above 92%, the yield reach can 90.2%.