Preparation Of Fe₃O₄ By Using Steel Pickling Waste Liquid As RAW Material And Its Application In Organic Synthesis

Before the forming,electroplating and spraying of steel,the surface of the steel is usually pickled to remove impurities and oxide layers on the surface.This process produces a large amount of steel pickling waste.Steel pickling waste not only corrodes hydraulic structures,but also affects the reproduction of aquatic plants.High concentrations of metal ions in the effluent also poison aquatic animals,and human health is affected as the food chain passes.With the increasingly severe environmental situation,how to effectively treat steel pickling waste liquid has become a research hotspot.Commonly used treatment methods include solvent extraction,concentrated crystallization,ion exchange,electrodialysis/membrane separation/diffusion dialysis,high temperature hydrolysis,etc.Compared with the traditional treatment methods,the treatment methods of steel pickling waste liquids have been paid more and more attention by researchers.It is one of the preparations of Fe₃O₄ from steel pickling waste liquid.In this paper,the Fe₃O₄ magnetic powder was prepared by simple co-precipitation oxidation method using hydrochloric acid pickled carbon steel waste liquid as raw material.The ratio of Fe³⁺/Fe²⁺in the reaction solution was monitored by the change of pH during the reaction,which provided a simple operation for the oxidative coprecipitation method.The effects of initial pH?pHo?and reaction temperature on the morphology,size and magnetic properties of the product were discussed.The products prepared by the same method using pure reagent iron salt as raw materials and the properties of the products obtained by the work were compared.A small particle size Fe₃O₄ nano-sized magnetic powder was prepared by this method,and its catalytic application in the synthesis of coumarin derivatives and quinoxaline derivatives was achieved,and the catalytic effect was compared with that of alfa reagent grade Fe₃O₄.This subject breaks through the traditional method of treating steel pickling waste liquid,and realizes turning waste into treasure.In this study,small particle size Fe₃O₄ magnetic powder was prepared from steel pickling waste liquid,which realized its catalytic application in the synthesis of coumarin derivatives and quinoxaline derivatives,which provided a powerful reference for the treatment of waste acid.