摘要
研究了以蛇纹石为原料制取高纯度活性氧化镁的工艺。以硫酸浸取蛇纹石矿石得到硫酸镁,以精制硫酸镁溶液为原料,氨水、碳酸氢铵为沉淀剂制取碱式碳酸镁前驱体,煅烧碱式碳酸镁前驱体得到高纯度活性氧化镁产品。考察了制取碱式碳酸镁的工艺条件,最佳工艺条件为:预氨pH值为9.6～9.7、镁离子与总铵(NH3+NH4+)摩尔比为0.46、氨与碳酸氢铵摩尔比为1.4。在此条件下,镁的沉淀率达到最大值89%。碱式碳酸镁前驱体最佳煅烧条件为:升温速率10℃/min,煅烧温度650℃,煅烧时间2h。在此条件下得到了碘吸附值为165.1mgI2/gMgO、柠檬酸活性值为3.05s、比表面积为78.03m2/g的高纯活性氧化镁。
Production of high-purity activated magnesium oxide from serpentine was investigated in this paper. First, magnesium sulfate was obtained through sulfuric acid leaching of serpentine. Then, the refined magnesium sulfate solution was mixed with ammonia and ammonium bicarbonate as precipitating reagent to produce basic magnesium carbonate precursor, which went through calcinations to generate high-purity activated magnesium oxide. The results showed that under the optimal operating conditions （aminated pH value at range of 9.6~9.7, reaction temperature at 40℃, molar Mg^2＋ to （NH3＋NH4＋ ） ratio of 0.46 ： 1, molar ammonia to ammonium bicarbonate ratio of 1.4 ： 1）, 89% yield of Mg2＋ is achieved. The optimal operating conditions for basic magnesium carbonate precursor calcination are： heating rates at 10 ℃/min, calcination temperature at 650℃, calcination duration for 2 h. Under these conditions, high purity activated magnesium oxide was obtained with iodine adsorption value of 165.1 mgI2/gMgO,citric acid activity value of 3.05 s and specific surface area of 78.03 m^2/g.
出处
《化工矿物与加工》
CAS
北大核心
2011年第11期5-8,共4页
Industrial Minerals & Processing
关键词
蛇纹石
活性氧化镁
高纯度
碱式碳酸镁
serpentine
activated magnesium oxide
high purity
basic magnesium carbonate
