切割钢渣活化过硫酸盐降解偶氮类染料酸性红73

切割钢渣是钢铁生产过程中的固体废弃物,如何有效处理和利用这些废渣具有减少环境污染、实现废物资源化的重要意义.本文选择河北邢台钢铁厂中切割钢渣为过硫酸盐(PS)活化剂,活化过硫酸盐(PS)去除水相中偶氮染料酸性红73(AR73),实验表明,25 mg·L~(-1) AR73在15 min内,其降解率为99.9%,TOC矿化率达58.6%.同时考察了钢渣投入量、PS浓度、初始pH值等影响因素对AR73降解效率的影响:随着PS浓度、钢渣投入量的增加,AR73的降解速率也逐渐增加;在pH为3～9时,AR73均可被有效去除,酸性条件更有利于AR73的去除.活性自由基猝灭实验表明,酸性红73的降解是通过自由基和非自由基两种机制实现的,且钢渣可多次回收重复利用.钢渣活化PS技术,还可有效去除蒽醌类染料(活性蓝19),其去除率为99.9%,矿化率可达92.0%;同时该技术对某印染废水(COD_(Cr)=5625 mg·L~(-1))的去除率达49.9%.本文所构建的切割钢渣活化过硫酸盐(PS)技术可应用于偶氮印染废水的处理,实现"以废治废"的目标.

Degradation of acid red 73 by persulfate activated by steel slag

steel slag is a kind of solid waste generated in the steel cutting process. It was chosen as an activator to activate persulfate (PS) to degrade an azo dye, acid red 73(AR73), in aqueous solutions. The results indicate that 99.9% removal of 25 mg·L^-1 AR73 was achieved within 15 minutes, and TOC mineralization efficiency was 58.6%. Results also show that the removal of AR73 increased with increasing PS dosage and steel slag loading. Effective removal could be achieved in solutions in a wide pH range, varying from 3 to 9, and low pH was more favorable. The radicals quenching experiment illustrates that radical and non-radical mechanisms play a joint role in the degradation of acid red 73(AR73). After 6 cycles of operation, steel slag still maintained high stability. 99.9% removal and 92.0% mineralization of the anthraquinone dye (reactive blue 19) were obtained in the steel slag-persulfate system, which also used to mineralize 49.9% of real dye wastewater. The Steel slag-persulfate system built in this study is potential for treating azo dye wastewater.