柴油脱硫菌Rhodococcus sp.的分离及其性质考察

石油产品中的硫经过燃烧以SOx形式排放到大气中,对环境造成了严重的污染。生物脱硫被认为可以有效补充甚至取代传统的加氢脱硫(HDS)。从土壤中分离纯化得到47株菌又经进一步复筛得到7株有明显脱硫效果的菌,最终选出一株降解二苯并噻吩(DBT)的高效菌,经鉴定为红球菌Rhodococcussp.定名为ZY-75。通过正交实验确定该菌株的最佳发酵条件为:温度为30℃,硫源DBT的质量浓度为94.0mg/L,氮源NH4NO3的质量浓度为2.0g/L,碳源甘油的质量浓度为5g/L,培养时间为4d,pH值为7.0。并且初步考察了该菌株对柴油的脱出率,优化其发酵条件后DBT降解率达68%,该菌株对抚顺石油二厂重油催化裂化柴油和南油催化裂化柴油中硫的脱出率分别达到24.50%和31.19%。

Isolation and Characterization for Diesel Oil Desulfurization Bacterium Rhodococcus sp.

Sulfur dioxide released into the atmosphere during combustion of fossil fuels is a serious environmental problem. Biodesulfurization using microbial is an effective way to compensate or can even replace the conventional hydrodesulfurization (HDS) method. Forty-seven strain bacteriums were isolated and pured from soil, from which seven strain bacteriums with obvious desulfurization were re-isolated. And at last the strain bacterium, named as ZY-75, which can degrade DBT, was isolated from the 47 ones and identified as Rhodococcus sp. Its optimal fermentation conditions through the orthogonal experiments are: temperature 30 ℃, mass concentration of sulfide DBT is 94.0 mg/L, mass concentration of nitride NH_4NO_3 is 2.0 g/L , mass concentration of carbide glycerin is 5 g/L, incubating time is 4 days and pH is 7.0. Under the above conditions, it's DBT degradable rate reaches 68%. Furthermore the remove rate for heavy FCC and FCC diesel oil from Fushun No.2 Refinery is tested, and the removal rates reach 24.50% and 31.19% , respectively.