摘要
为高效去除水体中的对硝基苯甲酸、开发新型水处理技术,提出以超声与单质锌联用降解水中的对硝基苯甲酸。考察了锌投加量、溶液初始pH、声功率及溶液初始浓度对拟一级反应速率常数(k0US/Zn)的影响,比较了US、Zn0和US/Zn03体系下的降解常数,并对US/Zn0体系的降解机理进行了初探。结果表明,以上4种因素对k0US/Zn均有很大影响,k0US/Zn分别在溶液初始pH为5、声功率为120 W、溶液初始浓度为0.04 mmol/L时达到最大值,且随着锌投加量的增加而增加。超声与单质锌在降解对硝基苯甲酸的过程中存在很好的协同作用,在最优条件下,k0US/Zn=0.052 min-1,分别是单独超声降解及单独锌降解的21.5倍和2.53倍。在联用体系中,主要是依靠OH·氧化及单质锌还原的相互加强来去除对硝基苯甲酸。
Degradation of p-NBA by ultrasound-Zn0 was investigated in order to develop a new method for aqueous pollutants control.Important factors including Zn0 dose,initial pH,ultrasonic power and initial p-NBA concentration were examined for their impacts on the pseudo-first-order constant of p-NBA degradation.The degradation mechanisms were investigated as well.The results indicate that ultrasound-Zn0 can effectively degrade pNBA and show significant promoting effects.All examined factors influence the rate constant.The optimal conditions are as follows: initial pH of 5,ultrasonic power of 120 W,initial p-NBA concentration of 0.04 mmol/L.Under the optimal conditions,k0 US/Znis 0.052 min-1,which is 21.5 times of kUSand 2.53 times of k0 Zn.The potential mechanisms are OH·oxidation and Zn0 reduction.
出处
《环境工程学报》
CAS
CSCD
北大核心
2014年第5期1797-1801,共5页
Chinese Journal of Environmental Engineering
基金
深圳市科技研发资金项目(JSF201006300042A)
国家自然科学基金资助项目(51278489)
