基于轻烧白云石-水化络合法的氧化镁制备工艺  

Preparation process of magnesium oxide based on light burned dolomite-hydration complexation method

作　　者：仉崇 刘红伟 林仁鹏 张衡 王晓敏[1] 王永祯[1,2] ZHANG Chong;LIU Hongwei;LIN Renpeng;ZHANG Heng;WANG Xiaomin;WANG Yongzhen(College of Materials Science and Engineering,Taiyuan University of Technology,Taiyuan Shanxi 030024,China;Shanxi Joint Laboratory of Coal Based Solid Waste Resource Utilization and Green Ecological Development,Taiyuan Shanxi 030024,China)

机构地区：[1]太原理工大学材料科学与工程学院,山西太原030024 [2]山西省煤基固废资源化利用与绿色生态发展联合实验室,山西太原030024

出　　处：《化工矿物与加工》2025年第4期26-36,共11页Industrial Minerals & Processing

基　　金：中央引导地方科技发展基金项目(YDZJSX2022B003)。

摘　　要：我国白云石资源分布广泛,储量丰富,容易开采,是制备镁系列产品的重要原料之一。氧化镁(MgO)具备优异的耐火性、绝缘性和导磁性等性质,已被广泛应用于建材、电子、国防等领域。当前以白云石为原料提取MgO的工艺大多存在工艺复杂、成本较高、生成残渣、污染环境等问题。本文以轻烧白云石为原料,采用水化络合法制备MgO。首先采用水化法将白云石中Ca、Mg进行初步分离,再通过络合工艺对水化产物中的Ca、Mg进行二次分离,最终制得纯度较高的MgO。通过考察轻烧白云石中主要共存元素Li、Na、Ca、K、Fe、Cu与Mg的质量分数比,确定了白云石粉料适宜的煅烧条件:煅烧温度为900℃、煅烧时间为3 h。通过考察水化产物中Ca与Mg的质量分数比,确定了轻烧白云石适宜的水化反应条件:水化温度为90℃、水化时间为0.5 h、搅拌速率为80 r/min。通过考察络合后提取的MgO纯度,确定了水化产物较适宜的络合反应条件:络合剂溶液pH为10、络合温度为50℃、络合时间为20 min、搅拌速率为60 r/min,在此条件下从轻烧白云石中提取的MgO纯度高达96.2%。本研究提出的工艺具有污染小、成本低、无残渣产生等优点,为高纯MgO的制备提供了一种新方法。China’s dolomite resources are widely distributed,abundant in reserves,and easy to exploit,making it an important raw material for the preparation of magnesium series products.Magnesium oxide(MgO)has excellent properties such as fire resistance,insulation and magnetic conductivity,and has been widely used in building mate-rials,electronics,national defense and other fields.At present,the processes for extracting MgO from dolomite as raw material mostly have problems such as complex process,high cost,residue generation and serious pollution.In this paper,MgO was prepared by hydration complex method using light burnt dolomite as raw material.Firstly,Ca and Mg in dolomite were preliminarily separated by hydration method,and then Ca and Mg in hydration products were separated again by complexation process,and finally MgO with high purity was prepared.By investigating the mass fraction ratios of the main coexisting elements Li,Na,Ca,K,Fe,Cu and Mg in light-burned dolomite,the suitable calcination conditions for dolomite powder were determined as follows:calcination temperature of 900℃and calcination time of 3 h.By investigating the mass fraction ratios of Ca to Mg in the hydration products,the suitable hydration conditions for light burnt dolomite were determined as follows:hydration temperature of 90℃,hydration time of 0.5 h,and stirring rate of 80 r/min.By investigating the purity of MgO extracted after complexation,the suitable comp-lexation conditions of hydration products were determined as follows:complexing agent solution pH=10,comp-lexation temperature 50℃,complexation time 20 min,and complexation stirring rate 60 r/min.Under these conditions,the purity of MgO extracted from light-burned dolomite reached 96.2%.The process proposed in this study has the advantages of low environmental pollution,low cost and no residue generation,providing a new method for the preparation of high-purity MgO.

关 键 词：白云石 氧化镁 水化反应 络合反应 水化产物 煅烧 

分 类 号：TQ132.2[化学工程—无机化工]