辽宁岫岩叶蛇纹石热处理产物的矿物学特征

MINERALOGICAL CHARACTERISTICS OF THE THERMAL TREATMENT PRODUCTS OF ANTIGORITE FROM XIUYAN, LIAONING

对辽宁岫岩叶蛇纹石进行了热活化处理 ,通过差热 热重分析 (DTA TG)、X射线粉晶衍射分析 (XRD)、红外光谱分析 (IR)和扫描电镜分析 (SEM) ,发现热活化温度达到 5 0 0℃时 ,叶蛇纹石八面体片中的羟基开始显著脱失 ,并出现镁橄榄石新物相 ,但仍然保持层的结构 ;当温度达到 5 5 0℃时 ,叶蛇纹石的层状结构被完全破坏 ;温度升高到 65 0℃时 ,镁橄榄石结晶度增高 ,并出现顽火辉石新物相 ;当温度达到 1 0 5 0℃时 ,镁橄榄石的含量略有减少 ,并出现较多的晶质顽火辉石物相。

The samples of antigorite from Xiuyan were treated by thermal activation. This study interprets the mechanism of thermal activation of antigorite by some experiment methods (such as XRD, IR, SEM, DTA and TG). The mechanism of thermal activation of antigorite is described as follows: When the temperature reaches 500 ℃, hydroxyl in octahedral sheet begins dehydrating , but the layer structure is maintained, and the new mineral phase forsterite is found. When the temperature reaches 550 ℃, the layer structure of antigorite is destroyed. When the temperature reaches 650 ℃, the crystallinity of forsterite is improved, then another new mineral phase enstatite appears. When the temperature reaches 1 050 ℃, the content of forsterite decreases, then more crystalline enstatite is found.