The Effect Of Dissimilatory Fe(Ⅲ) Reduction On The Decomposition Of Different Benzene Analogs In Paddy Soils

Dissimilatory Fe(III) reduction significantly influences the metabolize of organic compounds and the fate of inorganic compounds in anaerobic environment. Most of microbes of dissimilatory Fe(III) reduction can utilize H2 and organic electron donors so as to cause Fe(III) reduction and gain energy for growth. In the contaminated aquifers, dissimilatory Fe(III) reduction serves as the electron acceptor to oxidate the contaminants. The study of pure culture illuminate that some microbes of Fe(III) reduction can utilize aromatic compounds as electron donors, and stimulate the oxidation of aromatic compounds. So, using Fe(III) reduction to stimulate the degeneration of organic compounds in aquifers, and to strengthen the bioremediation of contaminated environments have expansive foreground, and this was gradually regarded by more and more researchers.In this paper, the typical paddy soils in our country were used, and the soil solutions were incubated under anoxic atmosphere. The effects of benzene analogs (toluene, aniline, phenol, benzoic acid) serve as sole electron donors and different concentrations of benzene analogs on dissimilatory iron reduction were studied, and determine if AQDS can adjust the effects; The potential of utilization of Fe(III) reduction on benzene analogs were also studied in nature soils and exhausted soils. Adopt the soil contaminated by phenol, the possibility of strengthen the degeneration of phenol by microbic Fe(III) reduction were investigated. Some conclusive results were obtained as following.(1) Microbes in the inoculum can utilize benzene analogs with different extent; different concentrations of benzene analogs have different effect on iron reduction, Fe(III) reaction rate of benzene acid was highest (53.99%), which of toluene was lowest (19.55%), and the Fe(III) reaction rate of different benzene analogs were lower than when glucose served as carbon source.(2) Different concentrations of benzene analogs have different effect on iron reduction. when the concentrations of aniline, phenol, and benzoic acid are between 1.0 and 2.0mmol/L, and the concentration of toluene is between 2.0 and 4.0mmol/L, dissimilatory iron reduction that depends upon the microorganism activities can be strengthened, and anthraquione-2,6 -disulfonate obviously promoted electrons transferred from the benzene analogs to...