Fe3O4/埃洛石复合材料制备及其对铅锌选矿 废水中有机物降解性能的研究

铅锌有色金属矿选矿废水中残留大量的有机选矿药剂，COD浓度高达165 mg/L，远超废水的国家排放标准，将其直接回用亦会对选矿指标带来不利影响。为降解废水中残留的有机药剂，使其达到排放或回用标准，通过热分解法将四氧化三铁（Fe₃O₄）纳米颗粒负载于埃洛石天然矿物表面，制备得到Fe₃O₄/埃洛石复合材料，并将其作为类芬顿反应的催化剂，用于选矿废水的催化降解。试验考察了Fe₃O₄/埃洛石复合材料制备过程中的升温速率、所制备材料中Fe₃O₄含量，催化反应中初始pH值、反应温度及H₂O₂投加量对选矿废水中COD去除效果的影响。结果表明：在热分解升温速率为2~5 ℃/min、Fe₃O₄含量为35%的条件下合成的复合材料催化性能最佳；在反应温度为30 ℃、初始pH为3、H₂O₂投加量为10 mmol/L、Fe₃O₄/埃洛石复合材料用量0.5 g/L的条件下，铅锌选矿废水中COD由165 mg/L降为39 mg/L，去除率达到76.35%，实现了选矿废水中COD的高效、低成本降解，净化后选矿废水达到一级排放标准。

Preparation of Fe3O4/Halloysite Composite Materials and Its Degradation Property for Organics in a Lead-zinc Beneficiation Wastewater

A large number of organic dressing agents remain in the beneficiation wastewater of lead-zinc non-ferrous metal ore,and the COD concentration is as high as 165 mg/L,which is far beyond the national discharge standard of wastewater.The direct reuse of the organic dressing agents will also bring adverse effects on the beneficiation indexes.In order to degrade the residual organic agents in wastewater and make it meet the discharge or reuse standards,Fe3O4 nanoparticles were loaded on the surface of natural mineral hallosite by thermal decomposition method for preparation of Fe3O4/hallosite composite material.The composite materials was used as a catalyst for catalytic degradation of mineral processing wastewater in Fenton-like reaction.The effects of temperature rise rate in preparation process,Fe3O4 contents,initial pH value,reaction temperature and H2O2 dosage on COD removal in mineral processing wastewater were investigated.The results showed that the best catalytic performance of the composite materials is obtained when the temperature rise rate of thermal decomposition is 2~5℃/min,and the Fe3O4 contents is 35%.Under the conditions of reaction temperature of 30℃,initial pH of 3,H2O2 dosage of 10 mmol/L and Fe3O4/hallosite composite materials dosage of 0.5 g/L,COD in lead-zinc dressing wastewater decreases from 165 mg/L to 39 mg/L,and the removal rate reaches 76.35%,realizing efficient and low-cost degradation of COD in the dressing wastewater.The dressing wastewater reaches the first-level discharge standard after purification.