富镁与贫镁坡缕石在热处理下的结构变化研究  

Structure Changes of Mg-rich and Mg-poor Palygorskite Under Heating

作　　者：颜文昌[1,2] 吴大清[1] 袁鹏[1] 陈鸣[1] 刘冬[1] 詹建华[3] 谭道永[1,2] 

机构地区：[1]中国科学院广州地球化学研究所,广东广州510640 [2]中国科学院研究生院,北京100049 [3]中国建筑材料工业地质勘查中心安徽总队,安徽合肥230001

出　　处：《矿物学报》2012年第4期475-480,共6页Acta Mineralogica Sinica

基　　金：中国科学院知识创新工程方向性项目(No.KZCX2-YW-QN101);国家自然科学基金(批准号:41072032)

摘　　要：研究了安徽明光富镁坡缕石和江苏盱眙贫镁坡缕石热处理后的结构变化,结果表明:富镁坡缕石八面体片对称性好,晶体结构稳定性高,结晶度高,热稳定性好;贫镁坡缕石八面体片中存在连续八面体空位,对称性差,晶体结构稳定性低,结晶度差,热稳定性差。在脱除结晶水和羟基过程中,富镁坡缕石由正交晶系转变为单斜晶系,层间距变小,孔道变形、塌陷但一直保持链层结构,显示晶质特性;而贫镁坡缕石的晶体结构发生折叠,链层结构逐步破坏,700℃煅烧后部分四面体片遭到破坏,虽然显示多晶特性为主,但开始出现非晶化现象。Structure changes of Mg-rich palygorskite from Mingguang, Anhui Province, China, and Mg-poor palygorskite from Xuyi, Jiangsu Province, China under heating were investigated. Compared with the Mg-rich palygorskite, Mg-poor palygorskite has continuous vacancy in ribbons and shows low symmetry of octahedron ribbon, high structure stability, high degree of crystallization, and high thermostability. During the removal of bound water and dehydroxylation, Mg-rich palygorskite changes from orthorhombic structure into monoclinic structure, and shows deformation and collapse of channels, but keeps layered structure and crystalline characteristic; Mg-poor palygorskite exhibits the structural folding, gradual damage of layered structure and polycrystal properties, and appears amorphous characteristic because of the damage of tetrahedron ribbons when heating at 700 ℃.

关 键 词：坡缕石 热处理 热稳定性 结晶度 晶体结构 

分 类 号：P578.964[天文地球—矿物学] P579[天文地球—地质学]