超声耦合Fenton强化污泥载体构建催化体系及性能

Construction of Heterogeneous Catalytic System Based on the Treatment of Excess Sludge Using Ultrasound Coupled with Fenton Oxidation and Its Performance

基于超声耦合Fenton技术,以剩余污泥为载体,同时将污泥活化脱水和金属负载过程整合,成功制备出一种高效稳定的非均相Fenton催化剂,对其结构和性能进行了表征,并探究了所制备催化剂对亚甲基蓝(MB)模拟废水的降解行为。结果表明,Fe元素能有效掺杂于污泥中,并在主要以Fe2O3的形式存在,且负载铁元素和载体中二氧化硅间形成了Si-O-Fe键,保证了催化的稳定性。在初始pH为4,反应时间80 min,H2O2投加量为4 m L/L,催化剂用量0.5 g/L的优化降解条件下,催化剂对MB的降解率可达98.7%;且重复利用5次后仍能保持较好的循环稳定性。体系中H2O2可以产生具有强氧化性的·OH,作用于吸附在催化剂表面的MB生成反应中间产物,后进一步被降解为CO2和H2O。

A stable and effective heterogeneous Fenton catalytic materials was successfully prepared by ultrasound coupled with Fenton technology, excess sludge used as carrier and the process of sludge activated dehydration and loaded metal was integrated. The structure and performance of as-prepared catalyst was fully characterized and the degradation behavior of methylene blue （MB） in simulated wastewater was studied. The results indicated that iron element was present in the catalyst in the form of Fe203, and new chemical bonds Si--O--Fe were formed between iron element and silicon dioxide, which ensured the stability of catalyst. Under optimum conditions of initial pH, reaction time, H2O2 dosage and catalyst dosage was 4, 80 min, 4 mL/L and 0.5 g/L respectively, the degradation rate of MB by catalyst reached 98.7% within 80 min. the catalyst still kept well reusability and stability aRer recycling 5 times. · OH with strong oxidizing property would generated by H2O2 in the system, which could attack the MB molecules adsorbed on catalyst surface to produce intermediate reaction products., the intermediate reaction products were further degraded to CO2 and H2O.