基于感应热固定床的CWPO降解偶氮染料实验研究

Dye wastewater heterogeneous CWPO treatment based on induction heating fixed bed reactor

感应热固定床(IHFB)作为新型热传递方式下非均相反应器,利用感应加热铁磁材料将热量传递至液相,形成固液界面高温微反应区,促进有机废水降解.实验以海绵铁为感应内核,采用浸渍焙烧法制备了C包覆表层负载NiO的感应热催化剂(mNiO/C),在传统催化湿式过氧化氢法(CWPO)中引入感应热代替传统加热,建立新的基于感应热固定床的CWPO工艺(iCWPO),使其在常温常压下实现对有机底物的高效降解.以直接紫D-BL模拟废水为目标污染物,考察了进水条件对iCWPO降解染料的影响,对感应热微观作用进行了分析,并用UV-Vis对降解产物进行了检测.结果表明,依赖于微界面高温的iCWPO降解效率明显高于常规加热的CWPO,彻底破坏了可见光区染料的显色基团NN键,对紫外光区苯环也具有一定的降解作用.

The induction heating fixed bed reactor （IHFB） was developed in a novel thermal transfer pathway in the aqueous heterogeneous reactions. Due to the high solid/liquid interface temperature generated from the ferromagnetic heating in the micro-reaction zone, the degradation of aqueous organic pollutants was promoted. In this work, we introduced IHFB into the ordinary catalytic wet peroxide oxidation （CWPO） to create a new technology, noted as iCWPO. In order to promote the selective heating, a nickel-impregnated and C-coated catalyst with magnetic core of sponge iron （mNiO/C） was prepared by calcinations. The direct violet D-BL dye wastewater was selected as a target to investigate the performance of iCWPO. The process mechanism in microcosm was analyzed, and the degradation products were detected by UV-Vis. The results showed that iCWPO is superior to the traditional CWPO due to much higher temperature on the reacting micro-surface. The most N=N coloring groups and some benzene ring in the direct violet D-BL dye molecule can be broken in the process.