Simultaneous Desalination and Glyphosate Degradation by a Novel Electro-Fenton Membrane Distillation Process

In this study, electro-Fenton and membranedistillationwere coupled for simultaneous desalination and TOC removal by utilizinga membrane-based electrode with the ability to bidirectionally transfervapor and oxygen and electrochemically synthesize H2O2. The industrial effluent from glyphosate production hashigh salinityand refractory organic contaminants. The removal of organics and therecycling of inorganic salts from this kind of water are challengingissues. In this study, electro-Fenton (EF) and membrane distillation(MD) were coupled in a single reactor utilizing a membrane-based electrode(Mem-GDE) with the ability to bidirectionally transfer vapor and oxygenand electrochemically synthesize H2O2. The operatingthermal conditions for MD significantly promoted Fenton reactionsand, thus, the removal of glyphosate. During operation, Fe speciesdeposited on the Mem-GDE and enhanced its catalytic activity and adsorptivecapacity, which markedly increased the apparent reaction rate constantof glyphosate by 6 times. This novel EF-MD process simultaneouslyremoved organics and concentrated the inorganics, which is very meaningfulfor decreasing the costs for subsequent crystallization and achievinghigh-quality crystal salts. This study provides an efficient methodfor the treatment of organic-inorganic hybrid wastewater.

Automated summary

In this study, electro-Fenton and membrane distillation were combined to remove salt and TOC from glyphosate wastewater. A membrane-based electrode was used to transfer vapor and oxygen bidirectionally and synthesize H2O2 electrochemically. The operating conditions of membrane distillation promoted Fenton reactions and greatly improved glyphosate removal. The deposition of Fe species on the membrane-based electrode enhanced its catalytic activity and adsorptive capacity, leading to a 6-fold increase in the apparent reaction rate constant of glyphosate. This novel process simultaneously removed organics and concentrated inorganics, reducing subsequent crystallization costs and producing high-quality crystal salts.