Influence of Light Calcining Hydration of Magnesite on MgO Sintering  

作　　者：LI Huan YU Jingkun KUANG Shibo 

机构地区：[1]School of Materials and Metallurgy, Northeastern University, Shenyang 110004, China

出　　处：《China's Refractories》2009年第3期23-28,共6页中国耐火材料（英文版）

摘　　要：Sintered magnesia clinker （also called sintered MgO ） was prepared with Mg（ OH）2 （prepared by light calcining hydration of magnesite ） and magnesite as starting materials, respectively, by the technical process ： light calcining （850 ℃ 1 h） → grinding → molding → firing （1 600 ℃ 3 h ）. The morphology and structure of light calcined MgO powders prepared with magnesite or Mg（ OH）2 were analyzed by XRD, SEM and FT-IR. The sinterability and microstructure of sintered magnesia prepared with magnesite or Mg（ OH） 2 were researched. The results showed that： （1） light calcined MgO powders prepared with magnesite or Mg （OH）2 were both face-centered cubic structure. The light calcined MgO prepared with magnesite had the residual of functional group CO3^2-, and that prepared with Mg （OH） 2 didn＇ t have CO3^2- , and was easy to break, which reduced the grinding time. （2） Because of the high activity of the light calcined MgO prepared with Mg（ OH） 2 and the catalysis of the water residual in the decomposing process of Mg（ OH） 2, the apparent porosity of sintered magnesia decreased to 0. 6% from 2.0% of before hydration, closed porosity decreased to 2. 8% from 6. 1%, and bulk density increased to 3. 46 g · cm^ -3 from 3.29 g · cm^ -1.Sintered magnesia clinker （also called sintered MgO ） was prepared with Mg（ OH）2 （prepared by light calcining hydration of magnesite ） and magnesite as starting materials, respectively, by the technical process ： light calcining （850 ℃ 1 h） → grinding → molding → firing （1 600 ℃ 3 h ）. The morphology and structure of light calcined MgO powders prepared with magnesite or Mg（ OH）2 were analyzed by XRD, SEM and FT-IR. The sinterability and microstructure of sintered magnesia prepared with magnesite or Mg（ OH） 2 were researched. The results showed that： （1） light calcined MgO powders prepared with magnesite or Mg （OH）2 were both face-centered cubic structure. The light calcined MgO prepared with magnesite had the residual of functional group CO3^2-, and that prepared with Mg （OH） 2 didn＇ t have CO3^2- , and was easy to break, which reduced the grinding time. （2） Because of the high activity of the light calcined MgO prepared with Mg（ OH） 2 and the catalysis of the water residual in the decomposing process of Mg（ OH） 2, the apparent porosity of sintered magnesia decreased to 0. 6% from 2.0% of before hydration, closed porosity decreased to 2. 8% from 6. 1%, and bulk density increased to 3. 46 g · cm^ -3 from 3.29 g · cm^ -1.

关 键 词：MAGNESITE HYDRATION MAGNESIA SINTERING Density 

分 类 号：TF065.1[冶金工程—冶金物理化学]