【摘要】 为揭示浸出液中Fe³⁺的形态分布对焙烧氰化尾渣中赤铁矿浸出效果的影响，研究了H₂C₂O₄、H₂C₂O₄-H₂SO₄和H₂C₂O₄-K₂C₂O₄对赤铁矿浸出效果的影响，并采用响应面法对H₂C₂O₄-K₂C₂O₄浸出赤铁矿工艺进行了优化。结果表明：Fe³⁺的形态分布直接影响赤铁矿的浸出效果。H₂C₂O₄与K₂C₂O₄作为除铁剂，n（H₂C₂O₄）/n（K₂C₂O₄）摩尔比、(C₂O₄^2-)_T过量倍数及浸出温度影响浸出pH，而pH和c(C₂O₄^2-)_T应满足浸出的Fe³⁺转化成Fe（C₂O₄）₃^3-,Fe³⁺只有以Fe（C₂O₄）₃^3-形态存在，才能缩短赤铁矿浸出时间、提高赤铁矿浸出效果。H₂C₂O₄-K₂C₂O₄除铁优化条件为：n（H₂C₂O₄）/n（K₂C₂O₄）=1.03、(C₂O₄^2-)_T为理论量的1.37倍、浸出温度94℃、液固比L/S=5mL/g、时间30min。在优化条件下，实际值和预测值分别为98.42%和97.73%，相对误差为0.69个百分点。各因素对除铁效果影响大小排序为(C₂O₄^2-)_T过量倍数、浸出温度、n（H₂C₂O₄）/n（K₂C₂O₄），其中n（H₂C₂O₄）/n（K₂C₂O₄）与浸出温度有一定的交互作用。H₂C₂O₄-K₂C₂O₄浸出焙烧氰化尾渣中赤铁矿结果进一步证明，草酸-草酸盐混合浸出体系是一种高效除铁剂，且浸出液中的铁资源化利用工艺简单，其优势是现有除铁剂无法比拟的。更多还原

【Abstract】 In order to reveal the influence of species distribution of Fe³⁺in the leachate on the leaching effect of hematite in roasting cyanide tailings,the leaching effects of H₂C₂O₄,H₂C₂O₄-H₂SO₄and H₂C₂O₄-K₂C₂O₄on hematite were studied.Response Surface Method （RSM）was used to optimize the leaching process of hematite with H₂C₂O₄and K₂C₂O₄.The results show that the species distribution of Fe³⁺affects the leaching effect of hematite,when H₂C₂O₄and K₂C₂O₄ were used as iron removal agents,n（H₂C₂O₄）/n（K₂C₂O₄）mole rate,the excess multiple of(C₂O₄^2-)_T,and temperature affect leaching pH value and c (C₂O₄^2-)_T,and they should be sufficient for Fe³⁺conversion to form Fe（C₂O₄）₃^3-.Fe³⁺exists only in form of Fe（C₂O₄）₃^3-,the leaching time of hematite can be shortened and the leaching rate of iron can be improved.The iron removal optimization conditions with H₂C₂O₄and K₂C₂O₄are as follows:n（H₂C₂O₄）/n（K₂C₂O₄）=1.03,(C₂O₄^2-)_T dosage of 1.37times of the theoretical amount,94℃，L/S=5 mL/g,and 30 min.Under the optimal conditions,the actual and predicted values are 98.42%and 97.73%respectively,and the relative error is 0.69percentage point.The effect of the factors on iron removal is sorted as (C₂O₄^2-)_Texcess ratio,leaching temperature,and n（H₂C₂O₄）/n（K₂C₂O₄）.Among them,the interaction between n（H₂C₂O₄）/n（K₂C₂O₄）and leaching temperature has some interaction.The results of H₂C₂O₄-K₂C₂O₄leaching hematite from the roasting cyanide tailings further prove that the oxalic acid-oxalate leaching system is an efficient iron removal agent.Moreover,the process of iron resource utilization in the leaching solution is simple,and its advantages are incomparable to the existing iron removal agents.更多还原