摘要
费托合成废水COD高达40~60 g/L,pH低至2~3,必须采用化学方法进行预处理才能有效续接生物处理方法。本研究利用氧化铜对模拟费托合成废水进行臭氧催化氧化降解实验,考察单独臭氧氧化、催化臭氧氧化、催化剂投加量、初始COD对模拟费托合成废水COD去除率的影响,并对COD的降解动力学进行分析。实验结果表明:对于COD的定量分析,与分光光度法相比,重铬酸钾滴定法测定COD的精确性比较高;单独氧化铜吸附和单独臭氧氧化对模拟废水COD的去除率为20%~30%;采用氧化铜和臭氧组合工艺,对模拟费托合成废水COD的去除率较高。当COD初始值为1 000 mg/L时,氧化铜投加量为1 g/L,反应120 min后对模拟费托合成废水的COD去除率达到76.62%;随着初始COD浓度的提高,COD的绝对降解量也成比例逐渐增大。CuO/O3体系氧化机制分析表明,·OH对模拟费托合成废水中小分子有机酸醇的去除发挥了主要作用。动力学分析结果表明,采用氧化铜催化臭氧氧化工艺,模拟费托合成废水COD的降解过程符合准一级动力学方程,相关性系数高达0.97以上。
Owing to the high COD concentration of 40-60 g/L and the low pH value of 2-3,Fischer-Tropsch wastewater should be pretreated with chemical technology first,and then the biological treatment.In this study,oxidation degradation of simulated Fischer-Tropsch wastewater was carried out through catalytic ozonation with copper oxide(CuO).The effects of ozone oxidation alone,catalytic ozone oxidation,CuO catalyst dosage and initial COD concentration on the COD removal rate of simulated Fischer-Tropsch wastewater were investigated,and the degradation kinetics of COD concentration was analyzed.Results show that,so far as the quantitative analysis of COD is concerned,the potassium dichromate titration method is more accurate than the spectrophotometry method in determining the concentration of COD.The removal efficiency of COD in simulated wastewater by Cu O adsorption or ozone oxidation alone is from 20% to 30%,while,in the CuO/O3 system,the removal efficiency of COD is increased greatly.The removal efficiency of COD in simulated wastewater reaches 76.62% after 120 minutes of reaction,when the initial COD value is 1 000 mg/L and the CuO dosage 1 g/L.Moreover,the absolute degradation of COD increases proportionally with the increase of the initial COD concentration.The oxidation mechanism of CuO/O3 system shows that ·OH plays a major role in the removal of small organic acids in simulated Fischer-Tropsch wastewater.Kinetic analysis results indicate that the degradation process of COD in FischerTropsch synthetic wastewater is based on quasi-first-order kinetic equation with the correlation coefficient of 0.97 or more.
作者
任慧宇
张鸿敏
贾青竹
REN Huiyu;ZHANG Hongmin;JIA Qingzhu(College of Marine and Environmental Sciences,Tianjin University of Science&Technology,Tianjin 300457,China)
出处
《天津科技大学学报》
CAS
2020年第2期40-44,56,共6页
Journal of Tianjin University of Science & Technology
基金
国家自然科学基金资助项目(21676203)。
关键词
费托合成废水
臭氧
氧化铜
重铬酸钾滴定法
Fischer-Tropsch synthetic wastewater
ozone
copper oxide
potassium dichromate titration
