Abstract

As the first part of a novel process proposed for copper extraction, selective dissolution of iron from chalcopyrite in oxalic acid solutions with hydrogen peroxide was studied. Despite the fact that both iron and copper are readily soluble in acidic conditions, it was found that oxalic acid provides altered solubility behaviors for these metals. It should be used to form iron (II) oxalate which has a higher solubility (0.008 g/100 g H₂O at 293 K) than copper oxalate (2.16 × 10^–10 g/100 g H₂O at 293 K), while hydrogen peroxide was used to provide an oxidative leaching environment to break the chalcopyrite structure. Under the examined leaching conditions where 100 g/L of H₂C₂O₄, 3 M of H₂O₂, 318 K of leaching temperature, 120 min of leaching time, 25 mL/g of liquid–solid ratio, and 400 rpm of stirring speed were applied, extraction rates of copper and iron from the chalcopyrite concentrate were almost 1.5% and 70%, respectively. Copper was found as a solid oxalate form in the residue obtained after the leaching process in these conditions.

Graphical Abstract

中文翻译：

---

草酸选择性逆向浸出富集固体中的铜

摘要

作为提出的一种新的铜提取方法的第一部分，研究了用过氧化氢将黄铜矿中的铁选择性溶解在草酸溶液中。尽管铁和铜都容易在酸性条件下溶解，但是发现草酸对这些金属提供了改变的溶解性。它应用于形成草酸亚铁（II），其溶解度（293 K下为0.008 g / 100 g H ₂ O）比草酸铜（293 K下为2.16×10 ^–10  g / 100 g H ₂ O）高，同时使用过氧化氢提供氧化浸出环境以破坏黄铜矿结构。在检查的浸出条件下，其中H ₂ C ₂ O ₄为100 g / L，施加3 M的H ₂ O ₂，浸出温度318 K，浸出时间120分钟，液固比为25 mL / g和搅拌速度为400 rpm，黄铜矿精矿中铜和铁的萃取率分别接近1.5％和70％。在这些条件下，在浸出过程后获得的残留物中发现铜为固体草酸盐形式。

图形概要