用天然碱液及水氯镁石制备硅钢氧化镁

介绍了一种采用纯碱-卤水法制备硅钢氧化镁新工艺。首先用天然碱液及水氯镁石制得的工业氯化镁反应制得碱式碳酸镁,再将碱式碳酸镁煅烧制备氧化镁。考察了影响硅钢氧化镁粒径及水化率的因素,确定了最佳工艺参数:氯化镁溶液浓度1.5mol/L,天然碱液浓度1.5～2.0mol/L,体积比(1.05～1.1)∶1,反应温度70～80℃,反应时间10min,搅拌速度200r/min,煅烧时采用低温逐步升温方式。此条件下制得的硅钢氧化镁具有纯度高、粒径小、水化率低等特点。

Preparation of Silicon Steel Magnesia by Sal-ammoniac Soda and Bischofite

A new process for producing silicon steel magnesia using sodium carbonate-bittern method was introduced.Firstly,the basic magnesium carbonate was produced by sal-ammoniac soda and industrial magnesium oxide from bischofite,then the basic magnesium carbonate was calcinated to prepare silicon steel magnesia.The factors of affecting the particle size and hydration rate of silicon steel magnesia were investigated,and the optimal process parameters were determined.The concentration of magnesium chloride was 1.5 mol/L,concentration of sal-ammoniac was 1.5-2.0 mol/L,the volume ratio was(1.05-1.1)∶1,reaction temperature was 70-80 ℃,reaction time was 10 min,stirring rate was 200 r/min,and calcination temperature was increased from low to high step by step.The silicon steel magnesia prepared under the conditions has high purity,smaller particle size and low hydration rate.