柴油脱硫菌的特性研究

针对传统加氢脱硫方法难以脱除柴油中含有的大量以噻吩、二苯并噻吩（DBT）等形式存在的含硫化合物，以DBT为模型化合物，筛选出以DBT为唯一硫源且降解DBT较好的菌株HT1，正交实验确定菌株发酵最佳条件为：温度30 ℃，硫源DBT质量浓度102.0 mg/L，氮源NH4NO3质量浓度2.0 g/L，碳源甘油质量浓度5 g/L，培养时间4 d，pH值7.0。硫源对菌株HT1的生长及脱硫效果的研究结果表明：硫源对菌株HT1的生长影响不大，但菌株HT1对以DBT为硫源的脱硫效果最佳。菌株HT1对其它含硫化合物的脱硫效果与含硫化合物的结构有关。菌株HT1对催化裂化柴油的脱硫率较低，有待进一步提高。

STUDY ON THE CHARACTERIZATION OF BACTERIAL STRAIN FOR DIESEL OIL DESULFURATION

Due to the conventional hydrodesulfurization is less effective to remove thiophene and dibenzothiophene(DBT) types of sulfur containing compounds in diesel fuel,bio-desulfurization is being concerned.A kind of bacterial strain,HT1,using DBT as sole sulfur source and having high DBT degradation function is screened out.The optimal ferment conditions for HT1 strain are obtained by orthogonal test design as follows: treating at 30 ℃,DBT concentration of 102.0 mg/L,NH4NO3 concentration of 2.0 g/L,glycerol concentration of 5 g/L,cultivation time of 4 d with pH value of 7.0.The effect of various sulfur sources on the growth and desulfurization performance of HT1 strain is investigated.Results show that the growth of HT1 strain with various sulfur sources is similar,yet the influence of sulfur sources on the DBT degradation is significant,the best degradation performance was observed with HT1 strain using DBT as sulfur source.However,the degradation of sulfur containing compounds by HT1 strain is also depended on the structure of the compound,and the sulfur removal rate of catalytic cracking diesel fraction by HT1 strain still needs to be improved.