以鐵改質活性碳結合過硫酸鹽系統降解全氟辛酸之研究

Abstract

This study was focused on PFOA decomposition in persulfate solution catalyzed iron-modified activated carbon. to by Fe/AC to decompose PFOA. With the process impregnation and calcination, the redox state Fe covered on AC can promote the generation of sulfate radicals and the elevation of decomposition of PFOA. In order to explore the different factors influence the performance, experiments were designed for the effect of pesulfate dosage, Fe/AC dose, Fe covered ratio, pH, temperature, ferrous ion and the radical inhibitors. The decomposition and defluorination efficiency of PFOA were higher in Fe/AC-PS system than that of PS system. Moreover, the PFOA removals increased with the increasing PS dosage. For the experiments of Fe/AC dose and Fe covered ratio, results indicated that the decomposition and defluorination efficiency of PFOA improved with the promotion of Fe/AC dose and Fe ratio but decreased if the amounts were excess. Under neutral condition, PFOA decomposition efficiency was better than that in acidic condition because too much sulfate radicals produced would hinder the oxidation, and the worst in base conditions due to the suppression by OH-. Compared the efficiency of catalysis by Fe2+ and Fe/AC, experiments results illustrated that Fe/AC is more effective based on the function of catalysis as well as adsorption. The tert-Butanol served as the radical inhibitor that result in the decline of the decomposition and defluorination efficiency of PFOA. It proved that tert-Butanol can scavenge the sulfate radicals.