【摘要】 介绍了以纯橄岩为原料,采用酸浸法制备七水硫酸镁的工艺方法。研究并讨论了硫酸浓度、酸浸温度、酸浸时间、矿粉粒度、搅拌速度等因素对纯橄岩分解和七水硫酸镁制备的影响。具体制备方法及工艺条件:将纯橄岩在700℃煅烧4 h,用4 mol/L的硫酸溶液于100℃处理2 h,过滤,滤液经双氧水氧化,用氨水调pH=7.0~8.0,过滤除杂得到滤液,滤液经冷却结晶,在40~45℃烘干2 h后得粗硫酸镁晶体;粗硫酸镁晶体经重结晶,得高纯七水硫酸镁晶体。在此工艺条件下镁的浸出率可达97.86%,产品纯度为99.1%。产品符合HG/T 2680—1995工业七水硫酸镁的要求。更多还原

【Abstract】 Technology for preparation of magnesium sulfate heptahydrate from dunite by acid leaching method was introduced.Influences of process conditions,such as concentration of H2SO4 solution,the temperature and time of acid leaching,mineral size and stirring velocity on the dissolution of dunite and on preparation of magnesium sulfate heptahydrate were studied.Detailed processing conditions were as follows:first dunite was calcined for 4 h at 700 ℃ and treated by H2SO4 solution with 4.0 mol/L at 100 ℃ for 2 h.Secondly,leaching solution was oxidized by H2O2 after filtering and ammonia was added in to adjust its pH at 7.0~8.0.After impurities were leached,the leaching solution was crystallized in cold.Crystals were dried at 40～45 ℃ by heat for 2 h and coarse magnesium sulfate was obtained.Then coarse magnesium sulfate was crystallized again,and high-purity magnesium sulfate heptahydrate would be obtained.Leaching rate of Mg2+ can reach 97.86% and the purity of product was 99.1% above under those conditions.Product could be comparable with the requirements of HG/T 2680—1995 industrial product standard.更多还原