摘要
针对中浸渣草酸除铁过程中产出的锌渣,采用氨水-碳酸铵浸出锌渣—锌粉还原浸出液—还原后液蒸发回收有价金属及C_(2)O_(4)^(2-)的工艺,研究影响铜和锌浸出的因素,确定锌粉还原浸出液中铜、镍和钴的工艺条件,并采用响应面法对铜和锌的浸出条件进行优化,研究还原后液中金属及(NH_(4))_(2)C_(2)O_(4)的回收工艺。研究结果表明,液固比和搅拌速度对锌的浸出率影响较小,NH_(3)·H_(2)O与(NH_(4))_(2)CO_(3)物质的量比、(NH_(4)^(+))TOT的过量倍数、浸出温度以及浸出时间对锌的浸出率影响较大。优化后锌的浸出条件如下:n(NH_(3)·H_(2)O)/n(NH_(4))_(2)CO_(3)=0.51/3.49、(NH_(4)^(+))TOT过量2.011倍、浸出温度为28.63℃。在该优化条件下,锌和铜的浸出率实测值分别为99.46%和58.84%,其预测值分别为101.19%和59.41%,浸出渣为铅银渣。采用锌粉还原浸出液中金属的工艺条件如下:锌粉量为0.11 g、还原温度和还原时间分别为16℃和15 min。还原后液连续蒸发产物为碱式碳酸锌和(NH_(4))_(2)C_(2)O_(4)。该技术解决了锌渣中锌、铜、镍和钴的回收以及草酸盐中C_(2)O_(4)^(2-)的回收问题,为全湿法回收中浸渣中铜、锌、镍及钴提供了一条新思路。
Aiming at the recovery of zinc and other metals from zinc slag produced in the iron removal process of neutral leaching residue using oxalic acid,a recovery technology leaching of zinc slag using ammonia-ammonium carbonate—reducing metals in the leachate using zinc powder—the recovering of valuable metals as well as C_(2)O_(4)^(2-)by evaporation of the post-reduction solution was proposed.The main research focused on the factors affecting the leaching rates of copper and zinc,as well as the conditions for zinc powder reduction to recover copper,nickel,and cobalt from the leachate.The response surface methodology was employed to optimize the leaching conditions for copper and zinc.Additionally,the technology for continuous evaporation of the reduction solution to recover zinc and(NH_(4))_(2)C_(2)O_(4)was explored.The results show that the liquid-solid ratio and stirring speed have a little effect on the leaching rate of zinc,while the molar ratio of NH_(3)·H_(2)O and(NH_(4))_(2)CO_(3),the excess multiple of(NH_(4)^(+))TOT,temperature and time have significant impact on the leaching rate of zinc.The optimized leaching conditions of zinc are as follows.n(NH_(3)·H_(2)O)/n(NH_(4))_(2)CO_(3)is 0.51/3.49,(NH_(4)^(+))TOT excess multiple is 2.011 and leaching temperature is 28.63℃.Under the optimum conditions,the experimental leaching rates of zinc and copper are 99.46%and 58.84%respectively,while the predicted values are 101.19%and 59.41%respectively,and the leaching residue is also known as lead-silver slag.The process conditions for reducing metals in the leachate using zinc powder are zinc powder dosage of 0.11 g,temperature of 16℃and reduction time of 15 min.The products of the continuous evaporation of the post-reduction solution are basic zinc carbonate and(NH_(4))_(2)C_(2)O_(4).This technology solves the problem of recovering zinc,copper and nickel from zinc slag and the recovery of C_(2)O_(4)^(2-)from oxalate,providing a new idea for the full-hydrometallurgical recovery of zinc,copper,nickel and cobalt from neutral leaching residue.
作者
党晓娥
阳丹
刘安全
DANG Xiaoe;YAND Dan;LIU Anquan(College of Metallurgical Engineering,Xi'an University of Architecture and Technology,Xi'an 710055,China;Jinduicheng Molybdenum Co.Ltd.,Xi'an 710076,China)
出处
《中南大学学报(自然科学版)》
北大核心
2025年第8期3345-3359,共15页
Journal of Central South University:Science and Technology
基金
陕西省自然科学研究计划项目(2018JM5133)。
关键词
锌渣
氨水
碳酸铵
浸出
优化
还原
蒸发
zinc slag
ammonia water
ammonium carbonate
leaching
optimization
reduction
evaporation
