摘要
化学还原/沉淀法是处理含铬废水的经典工艺,而亚铁Fe（II）是常用的还原剂。优化选择还原反应的pH值条件是提高反应速率和处理效果的关键环节。本文首先利用化学模拟软件Visual MINTEQ对不同pH值条件下Fe（II）还原Cr（VI）反应体系反应物和生成物的形态分布以及反应机理进行了理论分析,然后通过实验考察了pH值在1.5～7.0范围Fe（II）还原Cr（VI）的反应速率及其反应动力学。结果表明,当pH值在1.5～4.0时,反应速率随着pH值的升高而降低;当pH值在4.0～7.0时,反应速率随着pH值的升高而升高;pH值在4.0左右时,反应速率最小。在实际处理含铬废水过程中,酸性条件（pH=2.0～3.0）和中性偏酸性条件（pH=6.0～7.0）下利用Fe（II）还原处理含铬废水均有较快的反应速率和较好的处理效果。
Chemical reduction/precipitation is the traditional process used in the treatment of chro- mium-containing wastewater. Fe（Ⅱ） is one of the most important reductants used in this process. The optimum pH in the reduction reaction is a key factor which affecting the reaction rate and the efficiency of the treatment. The species of reactants and products and the mechanism of the reaction of hexavalent chromium reduced by ferrous was analyzed using the chemical simulation software Visual MINTEQ. And then the reaction rate and kinetics between pH = 1.5 and pH = 7.0 was investigated in the experiments. Under the acid condition （ pH between 1.5 and 4.0） , the reaction rate decreased with increasing pH. However, the reaction rate increased with increasing pH between pH = 4.5 and pH = 7.0. The minimal reaction rate was observed around pH = 4.0. The treatment of chromium-containing wastewater using ferrous reduction under the acid condition （pH =2.0 -3.0） and weakly acidic and neutral condition （pH = 6 ～7 ） has a fast reaction rate and a good effect.
出处
《黑龙江大学自然科学学报》
CAS
北大核心
2014年第3期356-360,421,共5页
Journal of Natural Science of Heilongjiang University
基金
国家创新研究群体科学基金资助项目(51121062)
水体污染控制与治理科技重大专项课题资助项目(2014ZX07405002)
城市水资源与水环境国家重点实验室(哈尔滨工业大学)自主课题资助项目(2014DX02)
关键词
含铬废水
PH值
亚铁
动力学
chromium-containing wastewater
pH value
ferrous
kinetics
