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Specific microbial desulfurization technology capable of selectively removing hydrodesulfurization difficult removal of aromatic sulfur compounds , is to achieve deep desulfurization of petroleum and its products effective technologies. Isolation excellent strains , breeding bacteria is to improve the efficiency of microbial desulfurization desulfurization ability of an important way. Paper as a study destination , carried out specific desulfurization strain isolation and identification , selection and optimization of desulfurization conditions and other aspects of research . This test from Daqing oilfield petroleum-contaminated soil isolated and screened to a higher specificity desulfurization desulfurization capacity bacteria HDBS-1, by conventional biochemical identification and 16S rDNA phylogenetic analysis to determine the strain of Enterobacter sakazakii , therefore, the bacteria named as Enterobacter sakazakii HDBS-1. Enterobacter sakazakii HDBS-1 by UV mutagenesis , DES mutagenesis and UV, DES compound mutation , got a desulfurization capacity highest HDBS-4. The colorimetric determination , mutagenesis strains produce 2-HBP DBT degradation of capacity 0.011726mmol / L, is the starting strain amount (0.002553mmol / L) of 4.5 times. Optimal dose of UV radiation mutagenesis time 17s, DES mutagenesis ( final concentration 0.3% ) treatment time of 25min. The HDBS-4 continuous passage 10 times, stable genetic traits . For higher power desulfurization of HDBS-4 medium and desulfurization conditions were optimized . Obtained through the single factor experiment optimum medium (/ L): glycerol 10mL, yeast extract 2g, DBT 20mg, potassium dihydrogen phosphate 2.44g, disodium hydrogen phosphate 12.03g, magnesium chloride 0.4g, manganese chloride 4mg, ferric chloride 1mg, calcium chloride 0.75mg, pH value of 7.0 to 7.5. And determine the inoculum was 6% , liquid volume was 20mL/250mL, 30 ℃, 300r/min shaking culture for 5 days. Desulfurization in the best conditions, the culture medium containing up to 2-HBP 0.0359mmol / L, is nearly three times before optimization , HDBS-1 strain of nearly 13 times .
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