Study on preparation of MoS_x@ZVI composite by carbothermal reduction synthesis and its treatment of acid orange G wastewater

MoS_x@ZVI composite was synthesized with molybdenite (MoS₂), limonite and anthracite by carbothermal reduction. Effects of molybdenite dosage, roasting temperature, anthracite content, and roasting time on the performance of the prepared MoS_x@ZVI for removing orange G (OG) were investigated. MoS_x@ZVI with the best performance was prepared by roasting at 1 000 ℃ for 60 min with 6% of molybdenum and 25% anthracite. MoS_x@ZVI prepared under the best conditions was analyzed by X-ray diffraction, scanning electron microscopy and energy dispersive spectrometry. The results show that a large amount of sulfide zero-valent iron with a core-shell structure is formed in the material, the core is Fe-Mo-C alloy, and the shell may be composed of molybdenum sulfide, FeS, C, molybdenum oxide and iron oxide. The degradation experiment results show that the removal rate of OG is above 90% when MoS_x@ZVI prepared under the optimal conditions is crushed to particle size smaller than 0.1 mm, and 400 mL OG simulated wastewater with a concentration of 200 mg/L is treated with 0.6 g of MoS_x@ZVI for 150 min within the initial pH range of 3.0-10.0.