Study On The Removal Of Carbon Disulfide And Thiophene From Crude Benzene

On the basis of collecting a great number of references, this thesis report the process for removal of carbon disulfide and thiophene which are comparatively abundant in crude benzene respectively by static-adsorption and over titanium silicalite(TS-1) by hydrogen peroxide.First of all, static-adsorption was studied to deal with carbon bisulfide, which is about 0.3-0.4 percent in crude benzene, it is known that this way has many advantages including lowly energy consumption, high removal effeciency, convenient operation, and no waste outgrowth. Many concretely works relating to adsorption have been done includ choice to the type and dose of activiated carbon, adsorption temperature, and adsorption time. Errant granule activiated carbon, which has large surface area has been adopt to adsorption, as to 0.0252g/L carbon disulfide-crude benzene solution, at 25℃, the dose of activiated carbon is 0.15g/mL, adsorption ratio can reach 82.6% after 7 hours. In the next, parallel adsorption experiments were carried out by using of activiated carbon regenerated through heating up in the stove, the results showed regeneration can not wiped out all the materials adsorbing in activiated carbon, these materials may reduce the volume of activiated carbon and minish adsorption ratio in the following adsoption.Secondly, aimed at thiophene, on one hand, signal parameter and orthogonal design experiments were carried out under the condition of chloromethylation reaction,the optimum removal parameters were:temperature at 75℃,V粗苯:V甲醛:V盐酸:=2:1:1, reacting time 6 hours; on the other hand, the process for removal of thiophene from crude benzene over titanium silicalite (TS-1) by hydrogen peroxide was studied, the factors affecting the reaction,including reaction time,reaction temperature, the dose of TS-1 and the dose of H2O2 were investigated. The influence of these factors was in the following order:dose of TS-1>dose of H2O2> reaction time>reaction temperature. The removal conditions of thiophene were optimized by orthogonal design with the goal of maximizing removal efficiency. The optimum removal parameters were:reacting time 8 hours, temperature at 75℃, nH2O2∶nC4H4S=4∶1 and TS-1 0.15%wt. Under the optimal conditions,the removal of thiophene was 99.58%. At last, the two methods were compared on the ground of removal efficiency, separating operation of reaction products, environment pollution and desulfurization expense, the feasibility and superiority of the removal of thiophene from crude benzene over titanium silicalite (TS-1) by hydrogen peroxide was firmly assured. A new and highly efficient method for organic-sulfur removal with the features of easy operation,mild reaction condition (low temperature and normal pressure) and low cost is worth to be commercialized.In the end, the kinetics of thiophene oxidation was also studied. The reaction rate can be expressed as:v = 4.6*10 ?3 [T hiophene ][ Catalyst ]1 .37[ H 2O 2]0.08under the condition of 348k, 101kpa. And the obvious reaction constant can be showed as: k = 2697 e ( ?37.21/ RT)...