【作者】 肖朝龙；

【导师】 肖连生；

【作者基本信息】 中南大学 ， 有色金属冶金， 2011， 硕士

【摘要】 本文以湖南张家界地区镍钼矿为原料,开发高效、低能耗、环境友好型镍钼矿处理新工艺,提出在盐酸体系中,采用氯酸钠氧化浸出镍钼矿,然后分别用叔胺萃取剂N235和螯合树脂M4195从浸出液中提取钼和镍,主要研究内容包括氯酸钠氧化浸出镍钼矿、N235萃取钼、M4195吸附镍,主要研究结果如下：对镍钼矿氧化浸出进行单因素实验,考察盐酸用量、氯酸钠用量、液固比、浸出时间及温度对镍钼浸出率的影响,最佳条件下,镍浸出率达到92%左右,而钼浸出率仅为60%左右。物相分析表明,原矿中镍钼硫化物被充分氧化；采用氢氧化钠溶液浸出酸浸渣,通过单因素实验和机理研究发现,酸浸中石膏(CaSO4·2H2O)的产生是钼浸出率较低的主要原因。采用N235—仲辛醇—磺化煤油体系萃取酸浸液中的钼,考察N235浓度、仲辛醇浓度、相比、振荡时间、温度对萃取的影响,并进行五级逆流萃取模拟实验,钼萃取率达98%以上,镍损失率小于1%；采用稀硫酸溶液洗涤负载有机相,考察硫酸浓度、洗涤时间、温度、相比对洗涤的影响,并进行五级错流洗涤实验,铁洗脱率达99.6%,钼损失率仅为0.1%左右；采用氨水溶液反萃钼,考察氨水浓度、振荡时间、相比对反萃的影响,最佳条件下,一级钼反萃率可达97%以上,基本达到分离富集钼及初步除杂的目的。萃钼余液采用黄钠铁矾法除铁,除铁率达到99.6%,溶液中铁含量降到0.037g/L左右,镍损失率仅为0.1%。采用M4195吸附除铁后液中的镍,考察料液pH值、接触时间对吸附的影响,并研究吸附过程中杂质的行为,最佳条件下,镍的穿透吸附容量为35.7g/L；采用硫酸溶液解吸镍,考察硫酸浓度、接触时间对解吸的影响,并研究解吸过程中杂质的行为,最佳条件下,镍解吸率为99%以上,高峰液含镍19.6g/L,除杂率均为99%以上。本工艺采用氯酸钠在盐酸体系中直接氧化浸出镍钼矿,避免了火法脱硫过程的烟气污染和钼挥发损失,并可同时浸出镍和钼。且氯酸钠性质稳定,易于运输、储存和生产操作。采用N235和M4195可有效从酸浸液中分离提取钼和镍,分别得到较高浓度的钼酸铵和硫酸镍溶液,初步除去大部分杂质。更多还原

【Abstract】 A novel process was put forward to treat nickel-molybdenum ore from Zhangjiajie, Hunan province in this paper. This environment-friendly process could treat nickel-molybdenum ore efficiently with low energy consumption. The process was described as oxidative leaching nickel-molybdenum ore in hydrochloric acid system using sodium chlorate, then extracting molybdenum and nickel from leach liquor using tertiary amine extracting agent N235 and chelating resin M4195 respectively. The main research contents included oxidative leaching of nickel-molybdenum ore, solvent extraction of molybdenum, adsorption of nickel, the main research results were listed as follows:The single factor experiments were carried out on oxidative leaching of nickel-molybdenum, and investigated the effect of hydrochloric acid consumption, sodium chlorate consumption, liquid-to-solid mass ratio, leaching time and temperature on leaching rate of nickel and molybdenum respectively, the leaching rate of nickel was about 92% under the optimum process, but the molybdenum was only 60% approximately. The phase analysis indicated that the sulfides of nickel and molybdenum in raw ore were adequately oxidized. The leaching of acid residue was conducted using sodium hydroxide solution; it was found that the low leaching rate of molybdenum in acid leaching was caused by the generation of gypsum according to single factor experiment and mechanics research.The experiments of extracting molybdenum from leach liquor were carried out using N235-sec-octyl alcohols-sulfonated kerosene, investigated the effect of concentration of N235 and sec-octyl alcohols, oil-to-water ratio, oscillatory time, temperature on extraction, then the five-stage simulation experiment of countercurrent extraction was conducted, the extraction rate of molybdenum was above 98%, the loss of nickel was less than 1%. The load organic phase was washed by dilute sulfuric acid solution, investigated the effect of concentration of sulfuric acid, washing time, temperature, oil-to-water ratio on wash process, and the five-stage cross flow washing experiment was conducted, the washing rate of iron was above 98%, the loss of molybdenum was only about 0.1%. The ammonia solution was applied to strip molybdenum from load organic phase, investigated the effect of concentration of ammonia, oscillatory time, oil-to-water ratio on stripping process, the stripping rate of molybdenum was above 97% under the optimum process, according to the above process, molybdenum was separated and enriched, and most of the impurities were removed preliminary.Iron in leach liquor was removed in the form of amarillite, and more than 99% of iron was removed, the concentration of iron dropped to about 0.037g/L, the loss of nickel was only 0.1%.Nickel in solution was adsorbed by chelating resin M4195, investigated the effect of pH value, contact time on adsorption, and studied the behavior of impurities in adsorbing process, the breakthrough adsorption capacity of nickel was about 35.7g/L under the optimum condition. Sulfuric acid solution was applied to desorb nickel from load resin, investigated the effect of sulfuric acid concentration, contact time on desorbing process, and studied the behavior of impurities, the desorbing rate was above 99%, the concentration of nickel in peak liquor was about 19.6g/L, the removal rate of impurities were all beyond 99%.This process applied sodium chlorate to leach nickel-molybdenum ore directly, it has the advantage of avoiding smoke pollution and molybdenum lost from pyrometallurgical desulfuration process, aslo leaching nickel and molybdenum simultaneously. In addtion, the chemical property of sodium chlorate is stable, and it’s easy to transport, store and operate in production. The molybdenum and nickel could be effectively extracted from leach liquor by N235 and M4195 respectively, and obtained ammonium molybdenum and nickel sulfate solution with high concentration, most of the impurities were removed preliminary.更多还原