非均相催化臭氧化降解水中苯酚动力学  

Degradation kinetics of catalytic ozone oxidation of phenol in water

作　　者：王兵[1,2] 刘璞真 任宏洋[1,2] 张悦[1] 李永涛[1,2] 

机构地区：[1]西南石油大学化学化工学院,成都610500 [2]中国石油HSE重点实验室西南石油大学研究室,成都610500

出　　处：《环境工程学报》2016年第7期3427-3433,共7页Chinese Journal of Environmental Engineering

基　　金：国家科技支撑计划项目(2011BAC06B05);中石油科技管理部科技开发项目(2011D-5008-01)

摘　　要：在常温常压下对MgO催化臭氧化降解苯酚的动力学进行了详细研究,考察了MgO加量、臭氧投加量、pH值、苯酚初始浓度和反应温度对催化臭氧化降解苯酚废水的反应速率常数k的影响,分析了多相催化臭氧化的反应活化能,构建了反应动力模型。结果表明,臭氧对苯酚的催化降解遵循表观拟一级反应动力学,且反应速率常数k随着MgO加量(20~80 mg·L^(-1))的增加而增大,在MgO加量为40 mg·L^(-1)时达到0.185 7 min^(-1);随着臭氧加量(0.54~5.5 mg·min^(-1))的增加,k从0.030 49 min^(-1)增大到0.217 77 min^(-1);随着溶液初始pH(1.7~10.15)的升高,k从0.087 75 min^(-1)增加到0.205 49 min^(-1);随着初始苯酚浓度(50~400 mg·L^(-1))的增加,k从0.253 68 min^(-1)降低到0.036 82 min^(-1);随着反应温度(10~50℃)的增加,k从0.120 62 min^(-1)增加到0.466 46 min^(-1)。证明了催化臭氧化降解苯酚的表观反应速率常数分别与催化剂加量、臭氧加量、pH和反应温度成正相关,与苯酚初始浓度则成负相关。反应活化能较低(Ea=2.616 7×104J·mol^(-1)),并且动力学模型计算数值与实际数据吻合良好(平均相对误差为8.9%)。The degradation kinetics of phenol in wastewater by the catalytic ozonation process was investigated. The effects of the MgO dosage,O_3 dosage,initial pH,temperature,and the initial concentration of phenol were studied. The activation energy pertaining to the heterogeneous catalytic ozonation reaction was analyzed,and a reaction dynamics model was built. The results indicated that the degradation of phenol followed the apparent pseudo-first-order kinetic model. With an increase in the MgO dosage（ 20 to 80 mg·L-1）,the apparent rate constant of phenol degradation reached 0. 185 7 min-1at a MgO dosage of 40 mg·L-1,and increased from 0. 030 49 to0. 217 77 min-1with an increase of the O3dosage（ 0. 54 to 5. 5 mg·min-1）. The rate constant increased from0. 087 75 min-1to 0. 205 49 min-1with an increase of the pH value（ 1. 7 to 10. 15）,but dropped from 0. 253 68min-1to 0. 036 82 min-1with an increase in the initial concentration of phenol（ 50 to 400 mg·L-1）,and expended from 0. 120 62 min-1to 0. 466 46 min-1with an increase in the reaction temperature（ 10 to 50 ℃）. The experiments proved that the apparent rate constants of phenol degradation in wastewater by catalytic ozonation had positive relativity with the MgO dosage,O3 dosage,initial pH value of the aqueous solution,and the reaction temperature,but had negative relativity with the initial phenol mass concentration. The activation energy was low（ Ea= 2. 616 7 × 104J·mol-1）,and the numerical dynamics model fitted well with the experimental data（ the average relative error was 8. 9%）.

关 键 词：催化臭氧化 苯酚 动力学 羟基自由基 模型 

分 类 号：X52[环境科学与工程—环境工程]