(658a) Peracetic Acid Activated By Reduced Graphene Oxide Catalytic Membrane for Micropollutants Removal from Wastewater

Emerging recalcitrant micropollutants (MPs) with high toxicity are frequently detected in various water sources, including 2,4-dichlorophenoxyacetic acid (2,4-D) from herbicides and methylene blue (MLB) from medical waste streams. Peracetic acid (PAA) has recently been applied as a potent yet cost-effective oxidant. Developing PAA activation methods based on the direct electron transfer (DET) mechanism is essential to the rational design of robust PAA oxidation systems targeting water decontamination. 2-D carbon materials with high electrical conductivity, like graphene oxide (GO) and reduced GO (rGO), could mediate the DET activation of PAA. Herein, we demonstrated, for the first time, an rGO membrane-activated PAA catalytic oxidation filtration system realizing MPs removal. We first investigated the oxidation efficacy of the rGO, PAA, and MPs mixture system and evaluated the MPs removal ratio in batch experiments. The rGO/PAA systems demonstrated over 80% removal of 2,4-D compared to only 20% removal using only PAA. The PAA and MPs mixture filtrating through an rGO membrane demonstrated over 50% removal of 2,4-D and 30% for MLB. Moreover, a 100-nm-thick rGO modified Nylon membrane used to purify wastewater containing 2,4-D in a crossflow system exhibited more than 30% catalytic removal of 2,4-D. Additionally, the rGO membrane systems also showed a degradation of MLB of more than 3 g/(m²â‹…h) with 25 ppm PAA. The catalytic performance of the rGO and PAA system was well described by pseudo-first-order kinetic. This high removal efficiency for agricultural organic contaminants suggests its potential application in degrading MPs.