Study On The Improvement Of The Carrier Of Desulfurated Bacteria H-412 Immobilized And Desulfurizating Performance

Biodesulfurization (BDS) has the advantages of cost- and energy-efficiency. Moreover, BDS can selectively remove sulfur from condensed thiophenes recalcitrant to hydrodesulfurization (HDS). It is expecting to be complementary or alternative to HDS for deep desulfurization of petroleum and its products. Immobilized method can solve the problem that dissociative bacteria faced, such as separate oil-water difficult, bacteria reuse and lifespan short, the ability of bear acid,alkali and impact bad, etc. And for BDS to reach the commercial application, it will attract more and more attention in the future. The key in this technology is select carrier and method.The author study on biodesulfurization used immobilized bacteria H-412.Firstly, the transfer additives were studied based on co-immobilization with PVA and SA. The desulfurization capacity of the bacteria H-412 in model oil was investigated under the presence of transfer additive. Moreover, the effect of transfer additives on the growth of H-412 was investigated. Adding transfer additives to the carrier, the effect on the volume ratio of oil-to-water and the desulfurization rate was investigated. The results showed that the transfer additives could improve the desulfurization capacity and the growth of the bacteria H-412 and Tween80 was more remarkable. The result showed that when the carrier contained 6% Tween80 the most remarkable effect was obtained. When the volume ratio of oil-to-water is 2:3, the desulfurization rate of DBT increased from 32.3% to 67.6%.Secondly, adsorption immobilization was studied using chitosan-modified as the carrier. The adsorption capacity and the effect of desulfurization performance was investigated. The results showed that N-alkyl chitosan had the better adsorption capacity than chitosan itself. The desulfurization performance was good, when the volume ratio of oil-to-water is 2:3, the desulfurization rate of DBT can still above 50%.Last, the stability of bacteria desulfurating performance via the two method was investigated. The results showed that all immobilized bacteria H-412 could repeatedly use. Comparing with free bacteria, both immobilized bacteria has low sensitivity and hight stability.