2,5-二氟硝基苯的厌氧降解特性

摘要

考察了2,5-二氟硝基苯(2,5-DFNB)的厌氧降解特性及F-对其厌氧降解过程的影响.实验结果表明:当初始2,5-DFNB质量浓度为5～100 mg/L时,随着降解时间的延长,2,5-DFNB对厌氧消化产甲烷的抑制效应逐渐减弱直至消失;在厌氧降解过程中,2,5-DFNB的降解基本无延滞期,但仅发生了硝基转化,并未实现还原脱氟;2,5-DFNB的厌氧降解动力学符合Andrews模型,最大比降解速率、底物饱和常数、底物抑制常数分别为5.9 mg/(g·h),67.7 mg/L,1 299.6 mg/L;质量浓度为10～80 mg/L的F-对2,5-DFNB厌氧降解过程影响甚小,而质量浓度大于100 mg/L时则产生了较严重的抑制作用.%The anaerobic biodegradation characteristics of 2,5-difluoronitrobenze (2,5-DFNB)and the effect of F-on the process were researched.The experimental results showed that:When the initial mass concentration of 2,5-DFNB was 5-100 mg/L,the inhibiting effect of 2,5-DFNB on methanogenesis was decreased gradually and disappeared finally with the extending of degradation time;During acclimation,2,5-DFNB could transform into corresponding fluoroaniline without any lag,but not reductive defluorination;The degradation kinetic data fitted the Andrews model well with 5.9 mg/(g · h)of maximum specific degradation rate,67.7 mg/L of substrate saturation constant and 1 299.6 mg/L of substrate inhibition constant;The inhibiting effect of F with 10-80 mg/L of 2,5-DFNB mass concentration on the anaerobic biodegradation process was small,but that with over 1 00 mg/L was great.