直流电场对红串红球菌NCC-1脱硫效率的影响及电刺激机理的初探

Electro-stimulation Mechanism and Desulfurization Ratio of Rhodococcus Erythropolis NCC-1 with the Presence of Direct Current

研究了脱硫菌——红串红球菌NCC-1在直流电场作用下的生长及脱硫状况,以及实际柴油体系中的脱硫效率,并对外加弱电流加速脱硫菌生长的机理进行了初探。实验表明,水相适宜范围的电流密度可以提高脱硫菌的脱硫效率,脱硫菌脱硫的最佳电流密度为0.72A/m2,该条件下,铂电极培养体系菌体比不加电培养体系提前48h完全降解0.2mmol/L二苯并噻吩(DBT)。比相同电流密度钛电极培养体系菌体提前24h。铂电极最佳电流密度下菌体对实际柴油的脱硫率可以达到67.4%,比钛电极培养体系菌体高11.7%,高于不加电24.6%。经验证,发现引起这种变化的主要原因是水的阴极电解产物吸附氢和氢气的比例不同,其中氢气对摇瓶培养菌体促进作用显著。

Growth behavior and desulfurization ratio of Rhodococcus Erythropolis NCC-1 with the presence of direct currents（ DC） were studied.The electric field-activated mechanism was also investigated.The results show that direct current can improve the desulfurization ratio of NCC-1 within an appropriate scope of current density.The optimized current density is 0.72 A/m^2.Using 0.2 mmol/L dibenzothiophene （ DBT） as a probe,the complete removal time of DBT by NCC-1 could be shortened on platinum electrodes,e.g.24 h less than that without the presence of direct electric fieldor 48 h less than that using titanium electrodes under a current density of 0.72 A/m2.The desulfurization ratio can reach 67.4% at platinum electrodes under optimized direct current density in a mixture of water to diesel fuel with a ratio of 1∶9.This value is 11.7% and 24.6% higher than those achieved on titanium electrode and in a system without the presence of direct electric field,respectively.This could be ascribed to the different ratio of adsorbed hydrogen to released H2 produced from water on the cathode.The released H2 could significantly promote the shaking culture of the bacterium.