白云石铵浸法制备高纯纳米氧化镁研究  

Study on Preparation of High-Purity Nano-Magnesium Oxide by Dolomite Ammonium Leaching

作　　者：王琦 杨保俊 朱梦龙 王百年 张涛 Wang Qi;Yang Baojun;Zhu Menglong;Wang Bainian;Zhang Tao(College of Chemistry and Chemical Engineering,Hefei University of Technology,Hefei,Anhui 230009)

机构地区：[1]合肥工业大学化学与化工学院,安徽合肥230009

出　　处：《非金属矿》2023年第6期24-27,31,共5页Non-Metallic Mines

摘　　要：以白云石煅粉为原料,采用铵浸法将其中Ca、Mg元素进行分离,再利用碳化法制备高纯纳米MgO,考察并确定了碳化反应、重镁水热解、碱式碳酸镁煅烧等工序较适宜的工艺条件。碳化反应工序为:碳化终点p H值为7.5,CO_(2)流率为0.4 L/min,反应温度为15℃,搅拌速率为400 r/min,此条件下MgO转化率可达87.79%。Mg(HCO_(3))_(2)溶液热解工序为:热解温度为95℃,热解时间为40 min,此条件下Mg(HCO_(3))_(2)溶液的热解率达到94.46%,热解中间产物为单斜晶系4Mg CO_(3)·Mg(OH)_(2)·4H_(2)O。4Mg CO_(3)·Mg(OH)_(2)·4H_(2)O煅烧工序为:煅烧温度700℃,煅烧时间1 h。在上述优化条件下,制备的MgO样品MgO质量分数达99.11%,X射线衍射(XRD)、场发射扫描电镜(FE-SEM)表征显示MgO样品为粒径约30 nm的立方晶型纳米MgO。Using dolomite calcined powder as raw material,the Ca and Mg elements were separated by ammonium leaching method,and then high-purity nano-MgO was prepared by carbonization method,and the more suitable process conditions for carbonization reaction,heavy magnesium water pyrolysis,basic magnesium carbonate calcination and other processes were investigated and determined as follows:carbonization reaction process:carbonization endpoint pH value of 7.5,CO_(2)flow rate of 0.4 L/min,reaction temperature of 15℃,stirring rate of 400 r/min;Under these conditions,the conversion rate of MgO could reach 87.79%.Mg(HCO_(3))_(2)solution pyrolysis process:pyrolysis temperature of 95℃,pyrolysis time of 40 min;Under these conditions,the pyrolysis rate of Mg(HCO_(3))_(2)solution reached 94.46%,and the pyrolysis intermediate product was monoclinic 4MgCO_(3)·Mg(OH)_(2)·4H_(2)O.4MgCO_(3)·Mg(OH)_(2)·4H2O calcination process:calcination temperature of 700℃,calcination time of 1 h.Under the above optimization conditions,the MgO content of the prepared MgO sample reached 99.11%,and the XRD and FE-SEM characterization of the sample showed that the prepared MgO sample was a cubic crystalline nano-MgO with a particle size of about 30 nm.

关 键 词：白云石 氯化铵 碳化法 高纯MgO 

分 类 号：TD973.4[矿业工程—选矿] TQ132.2[化学工程—无机化工]