Advanced oxidation treatment of aqueous atrazine by fixed-bed reactor packed with carbon-supported molybdenum disulfide

MoS2/carbon composites were prepared by affixing MoS2 onto carbon particulates and used as packing materials to establish persulfate advanced oxidation fixed-bed reactors (PS-FBR) for effective continuous-flow degradation of organic pollutants. Since MoS2 was a co-catalyst in accelerating the conversion of Fe3+ to Fe2+, an improved degradation performance against organic pollutants such as atrazine (ATZ) was achieved in this PS/Fe2+/MoS2FBR. Cost-effective materials of granular carbon, needle carbon, quartz particles, and MoS2 with different morphologies were compared during the preparation of MoS2/carrier composites. The results indicated that a higher adsorption capacity of both carriers and MoS2 was more plausible for ATZ degradation in FBR. After the systematic investigation of reaction conditions, a removal efficiency of 99 % for ATZ was achieved at pH 3-7, 2 mg/L Fe2, 2 mM PS, flow rate of 2 mL/min (cross-sectional area of 1.33 cm2). Meanwhile, this PS/Fe2+/MoS2FBR could be continuously operated for over 5 days with removal efficiency above 90 %. Importantly, a low Fe2+ concentration of 2 mg/L was sufficient in this system, which could limit the formation of iron sludge and ensure long-term operation.