电化学脱硝过程参数的响应曲面优化研究  

Optimization of electrochemical denitrification process parameters with Box-Behnken design

作　　者：范念文[1] 李正魁[1] 周涛[1] 赵琳[1] 吴宁梅[1] 

机构地区：[1]南京大学环境学院污染控制与资源化研究国家重点实验室,南京210046

出　　处：《环境工程学报》2013年第5期1785-1790,共6页Chinese Journal of Environmental Engineering

基　　金：江苏省自然科学基金重点项目(BK2010056);江苏省环保厅项目(201108);国家"水体污染控制与治理"科技重大专项(2012ZX07101-006;2013ZX07101-014)

摘　　要：以Ti/IrO2-TiO2-RuO2为阳极,Cu/Zn合金电极为阴极,在无隔膜电解池中对这一新构造电极对的脱硝氮性能进行了研究。为了有效结合阴极硝氮还原能力和阳极氧化能力,采用响应曲面法中的Box-Behnken设计优化了对电化学脱硝过程有显著影响的4个重要因素:氯化钠含量、电流密度、pH和初始硝氮浓度。优化结果表明,相对于pH和初始硝氮浓度,氯化钠含量和电流密度对脱硝性能影响更大,而阴极硝氮还原性能主要受初始硝氮浓度、pH的影响。以6 h内电极对脱氮百分率为响应量,优化得最佳电化学脱硝过程参数为:氯化钠含量,1 g/L;电流密度,24.99 mA/cm2;pH,1.81;初始硝氮浓度100 mg/L。在此实验条件下,6 h内电极对脱氮百分率预测值为99.84%。通过3次重复验证实验,确认实际6 h内电极对脱氮百分率为91.34%。预测值与实测值两者相差不大,由此可知,Box-Behnken设计是一种优化电化学脱氮实验参数的有效方法,经过优化后的电极对具有较佳的脱氮效率。This study investigated the performance of electrochemical denitrification using Ti/IrOz-TiO2-RuO2 as the anode and Cu/Zn as the cathode in an undivided cell. In order to obtain an ideal performing condi-tion of cathodic reduction of nitrate and anodic oxidation of the formed by-product, Box-Behnken design of re-sponse surface method was employed to optimize the factors that were NaC1 dosage, current density, pH and ini-tial nitrate concentration and which were proved to have a significant effect on electrochemical nitrate removal. Current density and NaC1 dosage had stronger effects on nitrate removal efficiency than initial nitrate concentra- tion and pH in the present study. The optimal value of NaC1 dosage, current density, pH and initial nitrate con- centration for nitrate removal efficiency are 1 g/L, 24. 99 mA/cm^2 , 1.81 and 100 mg/L, respectively, at which the predicted nitrate removal efficiency after 6 h electrolysis calculated with the fitted equation is 99.84% , as a-gainst the actual nitrate removal efficiency of 91.34% which was obtained through duplicate confirmatory experi-ments. The difference between the predicted and actual nitrate removal efficiency is minor, indicating Box-Be-hnken design can be effectively used to optimize the design for experiments on the electrochemical reduction of nitrate.

关 键 词：电化学脱硝 TI IrO2-TiO2-RuO2阳极 优化 Box-Behnken DESIGN 

分 类 号：X703.1[环境科学与工程—环境工程]