中文摘要：

[目的]为了更有效地去除废水中的偶氮染料,运用响应曲面法研究生物制备黄钾铁矾在草酸的协同作用下光催化降解甲基橙的动力学过程。[方法]通过氧化亚铁硫杆菌氧化硫酸亚铁生成黄钾铁矾,进行X射线衍射、扫描电子显微镜和傅里叶变换红外光谱表征,在XPA-7型光化学反应仪中进行甲基橙光催化降解,二次回归方程用于拟合试验数据和过程优化。[结果]甲基橙能有效地在紫外光照射下被黄钾铁矾/草酸体系催化降解,反应25 min降解率可达100%,并提出了可能的降解机制。[结论]光催化降解甲基橙的最佳反应参数是：黄钾铁矾装载量0.2 g·L^-1,草酸浓度3 mmol·L^-1,p H值为4。

英文摘要：

[ Objectives ] In order to more effectively remove azo dyes from wastewater, a response surface methodology was used to study the kinetic process of photocatalytic degradation of methyl orange （MO） in the presence of biosynthesized jarosite and oxalic acid. [ Methods ] Jarosite was synthesized through an oxidation of FeSO4 by Acidithiobacillus ferrooxidans. X-ray diffraction, scanning electron microscope and Fourier transform infrared spectrum were used to characterize as-biosynthesized jarosite. The photocatalytic degradation of MO was carried out in an XPA-7 photochemical reactor,and a quadratic model was developed to fit the experimental data for process optimization. [ Results] The results demonstrate that MO can be catalytically degraded well by 100% in the jarosite/ oxalic acid system under ultraviolet irradiation after 25 min and a possible mechanism was proposed. [ Conclusions ] Optimum reaction parameters for the photocatalytic degradation of MO were jarosite loading of 0.2 g·L^-1 , oxalic acid concentration of 3 mmol· L^-1 and pH value of 4, respectively.