草酸-硫酸体系协同浸出硫铁矿渣中铁的机理及工艺优化

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关键词：硫铁矿烧渣；草酸；浸出；铁；响应面

中图分类号：TFO9文献标志码：A

DOI：10.7652/xjtuxb202511003 文章编号：0253-987X（2025）11-0032-10

Abstract： To address the low recovery eficiency of iron resources from pyrite cinder and the inefficiency of conventional acid leaching methods，a synergistic leaching system of H2C2O4 1 H2SO4 is proposed. The optimization of process parameters，such as leaching time， temperature， liquid-solid ratio，and sulfuric acid concentration， is performed using response surface method. The synergistic leaching mechanism is analyzed through leaching kinetics and thermodynamics， and the morphology and phase compositions of samples before and after leaching are characterized.Results show that oxalic acid significantly enhances the iron leaching rate due to its strong complexation ability. The optimized H2C2O4-H2SO4 model，developed using response surface method，accurately predicts the leaching efficiency. Under the optimized conditions of 6 hours of leaching time， 90∘C temperature，a liquid-solid ratio of 6mg/L ，and 50% sulfuric acid concentration， the iron leaching rate from pyrite cinder reaches 98.62% ，with a deviation of only 0.37% from the predicted value. Oxalic acid preferentially complexes with iron oxides to form soluble while sulfuric acid accelerates its conversion to Fe2（SO4）3 through protonation. The leaching process is jointly controlled by interfacial chemical reactions and internal diffusion.Furthermore，ferrous oxalate dihydrate is successfully recovered from the leachate using a photo-induced reduction method， yielding crystals with high purity and intact structure. It provides an economical and environmentally friendly solution for the resource recovery of metallurgical waste.

Keywords： pyrite cinder; oxalic acid; leaching; iron； response surface methodology

随着全球资源的紧张和环境保护要求的日益严格，矿产资源的回收与再利用成为重要方向之一，特别是在冶金废弃物的处理与资源化方面。（剩余13344字）