【摘要】 研究Acidithiobacillus ferrooxidans对酸性水体中复合重金属共沉淀过程的促进作用。A.ferrooxidans显著地提高了共沉淀体系中Fe(II)离子的氧化速率及硫酸羟基铁氧体的形成。在A.ferrooxidans存在的条件下Cu(II)浓度降低至0.058 mmol/L,而Cd在生物体系中浓度降至最低0.085 mmol/L。Pb主要以铅矾形式沉淀,硫酸羟基铁氧体促进了残余铅离子的沉淀。通过XRD、SEM和FTIR等技术对形成产物进行系统表征。共沉淀体系中主要的组分为高结晶度的黄钾铁矾,而A.ferrooxidans促进施式矿物在一价阳离子缺乏的反应后期形成。A.ferrooxidans存在体系中较高的Fe(II)离子氧化速率和Fe(III)离子供应速度有利于多面体晶体形成及其晶粒尺径增加。复合重金属离子进入硫酸羟基铁氧体的晶体结构,通过A.ferrooxidans介导的共沉淀能够高效地将重金属离子从酸性废水中去除。更多还原

【Abstract】 This study investigated the promotion effect of A. ferrooxidans on complex heavy metals coprecipitation process. A. ferrooxidans significantly enhanced the ferrous oxidation, which also promoted the formation of iron-oxyhydroxysulphate. Cu(II) concentration reduced to 0.058 mmol/L in A. ferrooxidans inoculated system, and Cd also reduced to the lowest concentration(0.085 mmol/L). Pb was mainly immobilized as anglesite and iron-oxyhydroxysulphate promoted the removal of remanent Pb in solution. The precipitates are characterized by XRD, SEM, and FTIR analysis. The main component of the iron-oxyhydroxysulphate was well crystallized jarosite. A. ferrooxidans contributed to the formation of schwertmannite in later monovalent cation lack stage. Higher ferrous iron oxidation rate and Fe(III) supply rate in A. ferrooxidans inoculated system facilitated polyhedron crystal formation and the increase of particle diameter. Complex heavy metals could be incorporated into iron oxyhydroxysulphate crystal, and efficiently removed from acidic wastewater through A. ferrooxidans mediated coprecipitation.更多还原