【作者】 李静；

【导师】 刘志勇；

【作者基本信息】 石河子大学 ， 工程硕士（专业学位）， 2018， 硕士

【摘要】 新疆的煤炭资源极为丰富,预计资源总量全国第一。因此,发展以原料密集型为主的煤化工产业对于新疆民生建设、经济发展甚至维护国家西北安全均具有重大的现实意义和战略意义。中央新疆工作座谈会后,依托政策优势和资源优势,一些大型涉煤工程项目在短期得到了快速发展。但随之而来的则是对当地脆弱的生态环境、枯竭的水资源的冲击。煤化工行业中产生的废水含有酚、硫化物、氰化物、氨氮等多种有害物质,其中以氯酚类（2-CPs）物质含量最高。氯酚废水有难降解、污染性强、毒性大等特性,如何高效地处理氯酚废水是环境污染防治领域亟待解决的问题。本文采用溶胶-凝胶法,制备出BiFeO₃、ZnFe₂O₄、FeTiO₃三种异相含铁盐,采用SEM、FT-IR、XRD、UV-Vis等手段对其结构、形貌进行表征。通过光照条件下催化降解2-CP溶液,得出制备的三种物质具有一定的光催化性质,并对其性能进行对比。研究了催化剂的催化性能,探究了不同催化剂用量、pH值、双氧水用量等参数对三种含铁盐的Fenton-like效应在高压汞灯照射下的影响,并且得到了BiFeO₃最佳条件为:100 mL 40 mg/L 2-CP溶液,0.5 g/L催化剂,pH=7,0.05 mol/L H₂O₂时,光照下80min后2-CP降解率达100%,其催化效率最高。ZnFe₂O₄最佳条件为:100 mL 40 mg/L 2-CP溶液,0.5 g/L催化剂,pH=7,0.05 mol/L H₂O₂时,光照下120min后2-CP降解率为48.48%,其催化效率最低。FeTiO₃最佳条件为:100 mL 40 mg/L 2-CP溶液,0.4 g/L催化剂,pH=7,0.07 mol/L H₂O₂时,光照下120 min后2-CP降解率为67.84%,其催化效率较高的结论。本文对三种异相含铁盐在不同pH条件下降解2-CP过程表观动力学进行了研究,建立了不同初始浓度下三种物质降解2-CP的动力学模型,并由曲线拟合解得相应的参数,得出动力学模型。得出:BiFeO₃在酸性和中性条件下,2-CP的降解符合拟一级动力学模型,且pH值越低,动力学常数k_obs越大,反应速率越快,模型曲线吻合度较高。而ZnFe₂O₄和FeTiO₃ 2-CP的降解基本符合拟一级动力学模型,且pH值越低,动力学常数k_obs越大,反应速率越快,模型曲线吻合度较低。更多还原

【Abstract】 Xinjiang have extremely rich coal resources.It is estimated that the total amount of resources is the first in China.Therefore,the development of coal chemical industry focusing on raw material-intensive is of great practical and strategic significance to people’s livelihood construction,economic development of Xinjiang and even the maintenance of northwest national security.After the Central Xinjiang Working Symposium,relying on the advantages of policies and resources,some large-scale coal-related projects have developed rapidly in the short term.However,the impact on the fragile ecological environment and depleted water resources is accompanying.Wastewater from coal chemical industry contains many harmful substances such as phenol,sulfide,cyanide and ammonia nitrogen,among which chlorophenol（2-CPs）is the highest.Chlorophenol wastewater is difficult to degrade,highly polluting and toxic.How to treat chlorophenol wastewater efficiently is an urgent problem to be solved in the field of environmental pollution prevention and control.In this article,BiFeO₃,ZnFe₂O₄ and FeTiO₃ were prepared by sol-gel method,and their structures and morphologies were characterized by SEM,FT-IR,XRD and UV-vis.Through the catalytic degradation of 2-CP solution under light conditions,it is concluded that the prepared three substances have certain photocatalytic properties and even their properties are compared.The catalytic performance of the catalysts was studied,and the influence of different catalyst dosage,pH value and hydrogen peroxide dosage on Fenton-like effect of three iron-containing salts under high-pressure mercury lamp irradiation was investigated.The optimal conditions for BiFeO₃ were obtained as follows:100 mL 40 mg/L 2-CP solution,0.5 g/L catalyst,pH=7,and 0.05 mol/L H₂O₂.The degradation rate of 2-CP is reached 100%after 80min of illumination,which is the highest catalytic efficiency.The optimum conditions for ZnFe₂O₄ are:100 mL 40 mg/L 2-CP solution,0.5 g/L catalyst,pH=7,and 0.05 mol/L H₂O₂.The degradation rate of 2-CP is reached 48.48%after 120 min of illumination,which is the lowest catalytic efficiency.The optimal conditions for FeTiO₃ were as follows:100 mL 40mg/L 2-CP solution,0.4 g/L catalyst,pH=7,and 0.07 mol/L H₂O₂.The degradation rate of2-CP is reached 67.84%after 120 min of illumination,which showed a high catalytic efficiency.This article studied the apparent kinetics of the degradation of 2-chlorophenol by three heterogeneous iron salts under different pH conditions,and established the kinetic models of the degradation of 2-chlorophenol by three substances under different initial concentrations,and the corresponding parameters were obtained by curve fitting.The results show that the degradation of BiFeO₃ 2-CP conforms to the pseudo-first-order kinetic model under acidic and neutral conditions.At the lower the pH value,the larger the kinetic constant k_obs,the faster the reaction rate and the higher the coincidence degree of the model curve.However,the degradation of ZnFe₂O₄ and FeTiO₃ 2-CP basically conforms to the pseudo-first-order kinetic model.The lower the pH value,the larger the kinetic constant k_obs,the faster the reaction rate and the lower the coincidence degree of the model curves.更多还原