金焙砂酸浸液两段pH调控氧化法制备四氧化三铁新工艺  

Novel oxidation process with two-stage pH regulation for preparation of Fe_(3)O_(4) from acid leaching solution of gold calcine

作　　者：张霜华 郑雅杰 曹攀 赵云龙 ZHANG Shuanghua;ZHENG Yajie;CAO Pan;ZHAO Yunlong(School of Metallurgy and Environment,Central South University,Changsha 410083,China)

机构地区：[1]中南大学冶金与环境学院,湖南长沙410083

出　　处：《中南大学学报（自然科学版）》2021年第5期1407-1417,共11页Journal of Central South University:Science and Technology

基　　金：新疆维吾尔自治区高新技术研究发展计划项目(201515108);新疆维吾尔自治区略性新兴产业专项资金资助项目(201552)。

摘　　要：以金焙砂酸浸液为原料,通过单因素实验对CaO与NaOH两段pH调控氧化法制备Fe_(3)O_(4)新工艺进行研究,并在此基础上进行放大实验,对两段pH调控氧化法与石灰一段pH调控氧化法制备Fe_(3)O_(4)工艺进行对比分析。研究结果表明:在反应温度为80℃,一段pH为6.45,反应时间为1.5 h,二段pH为9,初始Fe^(2+)浓度为0.5 mol/L、搅拌速度为200 r/min、空气流量为1.2 L/min、反应时间为1.5 h和磁场强度为140 kA/m的最佳条件下,两段pH调控氧化法制备的Fe_(3)O_(4)产物中铁质量分数为65.00%,铁回收率为94.78%,Fe_(3)O_(4)产物与石膏副产物质量比为1.0:1.2;两段pH调控氧化法制备所得Fe_(3)O_(4)产物中铁质量分数为64.25%,铁回收率为93.78%;与石灰一段pH调控氧化法制备Fe_(3)O_(4)相比,铁质量分数提高11.76%,铁回收率提高8.24%,含砷石膏副产物产量降低41.67%。A novel oxidation process with two-stage pH regulation by CaO and NaOH for preparation Fe_(3)O_(4) was studied by single factor experiments using acid leaching solution of gold calcine as raw materials.The scale-up experiment was carried out,and the processes of preparing Fe_(3)O_(4) by oxidation method with two-stage pH regulation and lime one-stage pH regulation were compared.The results show that the mass fraction of iron in Fe_(3)O_(4) product prepared by oxidation method with two-stage pH regulation is 65.00%,the iron recovery rate is 94.78%,and the mass ratio of Fe_(3)O_(4) product to gypsum by-product is 1.0꞉1.2 when pH is 6.45 and reaction time in the first stage is 1.5 h,in the second stage,pH value is 9,the reaction temperature is 80℃,the initial Fe^(2+) concentration is 0.5 mol/L,the stirring speed is 200 r/min,air flow rate is 1.2 L/min,the reaction time in the second stage is 1.5 h,and the magnetic field is 140 kA/m.Under the best condition,the iron mass fraction of Fe_(3)O_(4) product prepared by oxidation method with two-stage pH regulation is 64.25%and the iron recovery rate is 93.78%.Compared with the Fe_(3)O_(4) product by oxidation method with lime one-stage pH regulation,the iron mass fraction increases by 11.76%,the iron recovery rate increases by 8.24%,and the output of arsenic-containing gypsum by-product is reduced by 41.67%.

关 键 词：酸浸液 硫铁矿还原 两段pH调控 氧化法 四氧化三铁 

分 类 号：TF831[冶金工程—有色金属冶金]