直流电场对脱硫菌红串红球菌NCC-1生长及脱硫性能的影响

Effect of Direct Current on Growth and Desulfurization Performance of Rhodococcus Erythropolis NCC-1

以专一性降解二苯并噻吩(DBT)的红串红球菌NCC-1为脱硫菌,以DBT为硫源,考察了加直流电场对脱硫菌在不同浓度DBT水相中生长和脱硫性能的影响,以及调控菌液pH对脱硫菌生长和脱硫性能的影响;同时考察了脱硫菌对柴油的脱硫性能。实验结果表明,当电流密度为0.52～1.01A/m2时,能有效促进脱硫菌生长,提高脱硫效率,最佳电流密度为0.72A/m2,当DBT初始浓度为0.20mmol/L时,DBT完全降解的时间为120h,比不加电场时缩短了24h;当DBT初始浓度为1.00mmol/L时,DBT浓度降至0.31mmol/L所需时间为72h,比不加电场时缩短了96h。此外,调控菌液pH能有效促进脱硫菌生长。脱硫菌用于柴油脱硫时,在电流密度为0.72A/m2、柴油与菌液体积比1∶9的条件下,总硫含量从606mg/L降至269mg/L,脱硫率为55.7%,比不加电场时高出12.9个百分点。

Effects of direct current （DC） electric field on desulfurization performance and growth of Rhodococcus erythropolis NCC-1 in aqueous phase with different concentration dibenzothiophene（DBT） were studied. Performance of Rhodococcus erythropolis NCC-1 in desulfurization of diesel oil was investigated with DBT as sulfur source under the DC electric field. Effects of regulation of the bacterial liquid pH on the desulfurization performance and the growth of Rhodococcus erythropolis NCC-1 were also investigated. The desulfurization performance and growth of Rhodococcus erythropolis NCC-I were improved by the DC electric field with current density 0.52 - 1.01 A/m^2 and yttrium titanium electrodes. When initial concentration of DBT was 0.20 mmol/L, its complete degradation needed 120 h under DC electric field of 0. 72 A/m^2, 24 h less than that without DC electric field. Lowering of DBT concentration from 1.00 to 0.31 mmol/L needed 72 h, 96 h less than that without DC electric field. Under the conditions of volume ratio of diesel oil to the bacterial liquid 1 ： 9 and DC electric field of 0.72 A/m^2, the sulfur content in the diesel oil was reduced from 606 mg/L to 269 mg/L, reaching a 55.7% desulphurization rate, 12.9 percentage point higher than that of without the DC electric field.