摘要
以盐湖卤水纳滤膜法提锂脱镁后的氢氧化镁渣为原料,采用碳酸氢铵碳化法分离镁和锂,采用煅烧-水化法除去镁化合物中的碳酸钙,再经轻烧制备高纯轻质氧化镁。碳化优化条件:反应温度为30℃,反应时间为2 h,碳酸氢铵与氢氧化镁物质的量比为1∶0.8,液固质量比为16。在此条件下锂的去除率为97.3%。煅烧-水化优化条件:煅烧温度为920℃,煅烧保温时间为40 min,水化温度为40℃,水化时间为30 min。在此条件下钙的去除率为97.2%。在700℃下轻烧水化镁化合物,制得纯度为99.2%、视比容为6.47 cm3/g的高纯轻质氧化镁。
Magnesium oxide was prepared from magnesium hydrate waste in lithium extraction process by nanofiltration of salt lake.The ammonium bicarbonate carbonation technique was employed to separate lithium and magnesium from the waste,the calcination-hydration technique was employed to remove the calcium,and followed by light burning to prepare high-purity magnesium oxide.Results showed that the optimum carbonation process involved the reaction temperature of 30 ℃,reaction time of 2 h,NH4HCO3/Mg（OH）2amount-of-substance ratio of 1∶0.8,and the ratio of liquid to solid of 16.The extraction yield of lithium was up to 97.3% under those conditions.The optimum process of calcination-hydration involved the calcinations temperature of 920 ℃,soaking time of 40 min,hydration time of 30 min,and hydration temperature of 40 ℃,and the calcium removal efficiency was 97.2%.After light burning process at 700 ℃,the purity and apparent specific volume of the prepared Mg O particles were 99.2% and 6.47 cm3/g,respectively.
出处
《无机盐工业》
CAS
北大核心
2015年第9期73-76,共4页
Inorganic Chemicals Industry
关键词
氢氧化镁渣
碳化
水化
氧化镁
magnesium hydroxide waste
carbonation
hydration
magnesium oxide
