2,4-二硝基酚厌氧生物降解动力学研究

Anaerobic Degradation Kinetics of 2,4-Dinitrophenol

研究了间歇试验条件下,2,4-二硝基酚(2,4-DNP)与葡萄糖共基质时的厌氧降解动力学.结果表明:2,4-DNP与葡萄糖能同时被微生物降解;葡萄糖浓度高低对2,4-DNP的降解影响不大,而2,4-DNP的存在明显影响COD的降解.当2,4-DNP浓度<225 mg/L时,其比降解速率随浓度增大而增大,浓度为225 mg/L时比降解速率达到最大;由于底物抑制,当2,4-DNP浓度>225 mg/L时,其比降解速率呈下降趋势.选用Andrews非竞争性抑制模型描述2,4-DNP厌氧降解动力学,对实验数据进行非线性拟合,求得模型参数qmax、Ks和Ki分别为3.24 mg/(h.g)、196.23 mg/L和165.91mg/L,实验数据与该动力学方程拟合较好.

With glucose as co-substrate, anaerobic degradation kinetics of 2,4-dinitrophenol （2,4-DNP） were investigated in batch culture. The results show that 2,4-DNP and glucose can be degraded by the bacteria simultaneously. Although the effect of COD on 2,4-DNP degradation was minimal, addition of 2,4-DNP effected COD degradation obviously. The rate of 2,4-DNP degradation increased with increasing initial 2,4-DNP concentrations up to 225 mg/L. Further increase in initial 2,4-DNP concentrations caused decrease in the rate of degradation because of substrate inhibition. Uncompetitive inhibition equation is proposed to describe the degradation of 2,4-DNP. With non-linear regression technology, the kinetic model parameter q max, Ks and Ki are found to be 3.24 mg/（h·g）, 196.23 mg/L and 165.91 mg/L respectively. The experimental data verification for the model equation is satisfactory.