高砷钴矿提钴新工艺研究

【作者】 滕浩；

【导师】 郑雅杰；

【作者基本信息】 中南大学 ， 有色金属冶金， 2010， 硕士

【摘要】 本研究以高砷钴铁精矿为原料,探讨和比较了硫酸浸出、硫酸化焙烧-硫酸浸出、氯酸钠作用下硫酸浸出、硫酸和硝酸混合浸出以及磁选后硫酸和硝酸混合浸出的提钴方法,并经过除杂制备硫酸钴。钴矿中的主要物相为Fe3O4,铁、砷、钴的含量分别为33.20%、18.78%、1.49%,其中钴大部分赋存于硫化矿中。分别采用硫酸浸出,硫酸化焙烧后硫酸浸出,氯酸钠作用下硫酸浸出,钴浸出率分别为23.51%、67.48%、49.91%。硝酸作用下硫酸浸出,当反应温度为60℃,反应时间为4小时,液固比为3：1,100g原料加入34mL硫酸和56.5mL硝酸时,钴浸出率达到96.35%。采用磁选-混酸浸出工艺可以降低成本。黄钠铁矾法除铁,当反应时间为6h,反应温度为93℃,溶液pH值为2.0,硫酸钠用量为理论用量时,铁去除率达到99%以上。氢氧化钠沉钴,当反应时间为1h,溶液pH值为9.0时,钴沉淀率达到99%以上。氢氧化钠除杂,当反应时间为2h,反应温度为90℃,液固比为9：1,5g干氢氧化钴加入18.4g氢氧化钠时,锌、砷去除率都达到99%以上,氢氧化钴中含钴64.8%。除杂后的氢氧化钴,经硫酸溶解、蒸发、冷却结晶、甩干得到硫酸钴产品,产品中钴质量百分含量达到25.69%,产品质量达到了企业标准。用硫酸溶液溶解氢氧化钴后,在溶液pH=4.0-5.0,反应温度60℃,反应时间1.5h时中和除铁、砷,得到的硫酸钴溶液中Co、Fe、As浓度分别为22.25g·L-1、0.009 g·L-1、0.041 g·L-1。采用氟化铵除去溶液中Ca、Mg,当氟化铵用量为1.8倍理论用量,反应温度为60℃,Ca、Mg去除率分别为98.51%、96.62%。P204萃取除Zn,当萃原液pH为3.5,P204体积分数为20%,皂化率为60%,协萃剂(TBP)体积分数为4%,混合时间为10min,萃取温度为室温,有机相与水相的体积比为1：1,Zn、Mn去除率分别为99.39%、49.02%,Co直收率为99.19%。P204萃取除杂,当萃原液pH为2.5,P204体积分数为10%,其它条件同P204萃取除Zn,Mn去除率为78.16%,Co直收率为98.9%。采用3级逆流萃取,Co直收率达到96.23%,Mn去除率为96.5%,溶液中Mn浓度仅为0.023 g·L-1。P507萃取分离Co和Ni,当萃原液pH为4.0,P507体积分数为10%,皂化率为70%,混合时间为5min,萃取温度为室温,有机相与水相的体积比为1：1,Co萃取率达到78.86%,Ni萃取率为3.93%。采用5级逆流萃取,Co萃取率达到99.72%,Ni去除率为98.7%,萃余液中Co浓度仅为0.041 g·L-1,Ni浓度为0.382 g·L-1。实验所得硫酸钴产品质量远高于HG／T 2613-2005化学纯度要求。更多还原

【Abstract】 The raw material of the research is an cobalt ore with high As. In this study, the leaching methods of the sulfuric acid leaching, roasting-sulfuric acid leaching, sulfuric acid leaching under the action of sodium chlorate, sulfuric acid and nitric acid leaching and after magnetic separation sulfuric acid and nitric acid leaching, were discussed and compared. Then sulfate cobalt was prepared after removing impurity.The main phase in the ore is Fe3O4.The concentration of cobalt, iron, arsenic are 1.62%,33.35%,23.26% respective. The cobalt is mainly cobalt sulfide.Using the methods of sulfuric acid solution leaching, roasting-sulfuric acid leaching, sulfuric acid leaching under the action of sodium chlorate, the leaching rate of Co are 16.86%,67.48%,49.91% respective.In the process of nitric acid oxidation leaching with sulfuric acid, the leaching rate of Co is 96.35% when nitric acid and sulfuric acid addition volume are 56mL and 39mL in 100g cobalt ores, reaction time is 4h, reaction temperature is 60℃, the ratio of liquid to solid is 3:1. The cost can be reduced using the method of magnetic separation and mixed acid leaching.When the reaction time is 6h, the reaction temperature is 93℃, the solution pH is 2.0, the dosage of sodium sulfate is theoretical dosage, the iron removal rate reached 99% with the method of amarillite.When the reaction time is 1h, the solution pH is 9.0, the cobalt deposition rate arrived 99% with the method of precipitatation. When the reaction time is 2h, the reaction temperature is 90℃, liquid to solid ratio is 9:1,18.4g sodium hydroxide is added into 5g dry cobalt hydroxide, the zinc and arsenic removal rate reach 99%. The cobalt content in the obtained cobalt hydroxide is 64.8%. Cobalt sulfate products obtained through sulfuric acid dissolution, evaporation, cooling crystallization, drying, the cobalt content in the cobalt sulfate reached 25.69%.After cobalt hydroxide dissolved by sulfuric acid solution, using the neutralization method to remove Fe and As at the conditions of solution pH 4.0-5.0, reaction temperature 60℃, reaction time 1.5h, in the obtained cobalt sulfate solution the concentration of Co, Fe, As were 22.250g·L-1,0.009 g·L-1,0.041 g·L-1. Ammonium fluoride solution used to remove Ca, Mg, when the dosage of ammonium fluoride is 1.8 times the theoretical amount, the reaction temperature is 60℃, the removal rates of Ca, Mg were 98.51%, 96.62%.Removing Zn through solvent extraction by P204, when the pH value of the water phase is 3.5, volume fraction of P204 is 20%, the saponification rate is 60%, volume fraction of synergistic extractant(TBP) is 4%, mixing time is 10min, extraction temperature is room temperature, volume ratio of organic phase to water phase is 1:1, the extraction rate of Zn, Mn are 99.39%,49.02%, and the direct recovery of Co is 99.5%.Removing manganese through solvent extraction by P204, when the pH value of the water phase is 2.5, volume fraction of P204 is 10%, and the other conditions were the same as removing Zn, the extraction rate of Mn is 78.16%and the direct recovery of Co is 99.5%. Through three-stage extraction by P204, the direct recovery of cobalt can up to 96.23%, the removal rate of Mn is 96.5%,and the concentration of Mn is only 0.023 g·L-1.Separating nickel and cobalt through solvent extraction by P507, when the pH value of the water phase is 4.0, volume fraction of P507 is 10%, the saponification rate is 70%, mixing time is 5min, extraction temperature is room temperature, organic phase to water phase volume ratio is 1:1, the extraction rate of Co and Ni are 78.86% and 3.93%.Through three-stage counter current solvent extraction by P507, the direct recovery of cobalt can up to 96.23%, the removal rate of Ni is 98.7%, and the concentration of Co and Ni are 0.041 g·L-1 and 0.382 g·L-1 in the extraction raffinate.In the experimental process the quality of cobalt sulfate obtained outclass the requirements of chemical purity of HG/T 2613-2005.更多还原