硫化物金精矿及焙砂水溶液氯化提金研究

CHLORINE LEACHING OF GOLD—BEARING SULFIDE CONCENTRATE AND ITS CALCINE

本文对广东河台地区硫化物金精矿进行了水溶液氯化和阴离子交换树脂在浆提金的工艺研究,探讨用此工艺处理该金精矿及其焙砂的可行性.在小型实验的基础上进一步作了公斤级试验,研究了氯气用量、添加剂、浸取时间和树脂在浆对金浸出的影响.金浸出率可达96-98%,树脂吸附金的吸附率大于98%.同时,还探讨了载金树脂淋洗时硫脲浓度、酸浓度、淋洗时间和温度对金解吸的影响,金的解吸率可达98%.根据本研究结果,提出了水溶液氯化—树脂在浆法处理该金精矿的原则流程.

In view of limitation imposed on cyanide disposal by enviromental protection there is general interest in developing safe non-toxic substitutes for cyanide in gold leaching processes.Chlorine leaching,as a potential alternative to the conventional cyanidation for extraction of gold,was tested on sulfide concentrate and its calcine from the Pearl River area,South China.The sulfide concentrate contains Au 50.4 g/t,Ag 24.5 g/t,Cu 3.19% and S 20.59%.The mineralogical analysis shows that gold is attached to or enclosed in pyrite and is localized partly in chalcoprite and bornite. The feasibility using RIP and RIL (resin in pulp and in leaching)techni- que in chlorine leaching of gold-bearing sulfide concentrate and its calcine was discussed.A series of leaching tests were carried out to study the effe- cts of various parameters on extraction of gold.Exprimental results showed that under the optimal leaching conditions the extraction/of gold in the conce- ntrate can be over 96%.The adsorption of gold from leach solution and elution of gold from the loaded ion exchange resin(410 anion exchange resin) with acidic thiourea solution were also studied.A flowsheet for recovering gold from sulfide concentrate and its calcine was proposed based on the experimental results from bench tests.