pH值对“Fe^0-厌氧微生物”体系去除2,4,6-三氯酚过程的影响

Effect of pH values on process for removal of 2,4,6-trichlorophenol by Fe^0-anaerobic microbe system

考察了pH值对"Fe0-厌氧微生物"体系降解2,4,6,-三氯酚(2,4,6-TCP)效果的影响,结果表明:pH值是影响"Fe0-厌氧微生物"体系降解2,4,6-TCP效果的重要参数,初始pH值直接影响微生物活性和铁腐蚀,进而影响过程pH值变化,反过来又影响铁腐蚀和微生物活性,pH 7.0～9.0的中性偏碱范围较适于厌氧微生物生长。Fe0与微生物对目标污染物的降解具有协同促进作用,其协同促进机制表现在3方面:Fe0与微生物对体系过程pH值具有互补调节作用,可将体系的pH值调节值适于微生物生长的中性范围;Fe0腐蚀产生的Fe2+和H2可为微生物代谢提供电子对和营养物质,从而促进生物还原脱氯的进行;Fe0的腐蚀过程直接对氯代有机物还原脱氯,而微生物又可促进Fe0腐蚀。

The effect of pH value on the degradation effect of 2,4,6-trichlorophenol （2,4,6-TCP） by ＂Fe^0-anaerobic microbe＂ system was observed and studied, and results show that pH value is an important parameter for removing 2,4,6-TCP by ＂Fe^0-anaerobic microbe＂ system. Initial pH value directly affects microorganism activity and iron corrosion, and then affects the change of pH value in the process, which, in turn, influences microorganism activity and iron corrosion. The optimal range of pH value for anaerobic microorganism growth is 7.0 - 9.0. Fe^0 and microorganism have a synergistic promoting effect on the reductive dechlorination of 2,4,6-TCP. The mechanism of the synergy shows in three aspects： Fe~ and microbial play complementary role to regulate the pH value to neutral range which is suitable for microbial growth; Fe2＋ and H2 produced by the corrosion of Fe~ serves as electron donor and nutrient substance for microbial metabolism, thus promoting the transformation of 2,4,6-TCP;Fe^0corrosion makes chlorinated organics degraded by reductive dechlorination directly, and microbial oromotes the corrosion.