反应温度对碱式碳酸镁结构及晶形影响的研究

以硼镁肥处理后所得硫酸镁溶液为原料，采用碳铵法在55～100 ℃制备碱式碳酸镁。采用扫描电镜（SEM）、X射线衍射（XRD）等分析测试手段对所得产品进行表征，确定不同温度制备的碱式碳酸镁的结构及晶体形貌。研究结果表明反应温度与碱式碳酸镁所含结晶水的个数和晶体形貌的关系为：在55～60 ℃制备的产物约含5个结晶水，晶形呈针状；在65～70 ℃制备的产物含有6个结晶水，晶形呈絮状、片状；在75～80 ℃制备的产物约含8个结晶水，晶形呈棉棒状；在85 ℃制备的产物含有6～7个结晶水，晶形由棉棒状断裂向球状过渡；在90～95 ℃制备的产物含有4个结晶水，晶形呈球形；在100 ℃制备的产物约含3个结晶水，球形结构被破坏。

Study on effects of reaction temperature on structure and morphology of basic magnesium carbonate

Taking magnesium sulfate solution from the treatment of boric magnesium fertilizer as the raw material,basic magnesium carbonate was produced by ammonium bicarbonate method at 55~100 ℃.Products were characterized by scanning electron microscopy(SEM),X-ray diffraction(XRD),and other means,the structures and crystal morphologies of the basic magnesium carbonate prepared at different temperatures were determined.Results showed the relationship of reaction temperature and the numbers of crystal water and morphologies of basic magnesium carbonate was as follows:when at 55~60 ℃,product had about 5 crystal waters and the morphology was in the needlelike;at 65~70 ℃,6 crystal waters and morphologies are floccus and flakelike;at 75~80 ℃,8 crystal waters and morphology is cotton rodlike;at 85 ℃,6~7 crystal waters and morphology is in a transition state from cotton rodlike to sphericallike;at 90~95 ℃,4 crystal waters and morphology is sphericallike;and at 100 ℃,3 crystal waters and spherical shape was broken.