Microbial Removal of Dibenzothiophene from Crude Oil Distillate Fractions

Thiobacillus thioxidans was used to remove dibenzothiophenes (dbts) from various distillate fractions (light oil; b.pt 200 °c, medium oil; b.pt 300 °c and heavy oil; b.pt 360 °c) obtained from pakistani crude oil. desulphurization rate of dibenzothiophene (dbt) was studied in virgin and microbially treated samples. significant biodesulphurization was noticed in case of thiobacillus thioxidans inoculations i.e. 62.41 %, 64.33 %, and 66.22 % in light, medium and heavy fractions, respectively. the effect of inoculation time was also studied and it was observed that maximum depletion of dbt has been made with 12 hr inoculation. it was further observed that dbt concentration increased along with the b.pt of fractions i.e. 290, 415, and 450 ppm respectively in light, medium and heavy fractions. the study is very helpful from environmental point of view to deplete the oil in sulphur before being marketed