低品位硅藻土无熟料胶凝材料制备及机理研究  

Study on Preparation and Mechanism of Clinker-Free Cementing Material of Low Grade Diatomite

作　　者：杨立智 夏举佩[1,2] Yang Lizhi;Xia Jupei(Faculty of Chemical Engineering,Kunming University of Science and Technology,Kunming,Yunnan 650500;Yunnan Key Laboratory of Energy Saving and New Materials in Pnosphorus Chemical Industry,Kunming,Yunnan 650500)

机构地区：[1]昆明理工大学化学工程学院,云南昆明650500 [2]云南省磷化工节能与新材料重点实验室,云南昆明650500

出　　处：《非金属矿》2024年第2期10-14,共5页Non-Metallic Mines

基　　金：国家自然科学地区基金(22068019)。

摘　　要：为提高低品位硅藻土在建筑材料领域利用率,减少堆存量,本试验采用石灰(钙质)、Na_(2)SO_(4)协同激发活化改性低品位硅藻土制备胶凝材料,研究了其强度变化并通过X射线衍射(XRD)仪、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、傅里叶变换红外光谱(FT-IR)仪探讨了作用机理。结果表明,低品位硅藻土的最佳活化改性温度为850℃,胶凝材料中CaO与SiO_(2)摩尔比为1.4,Na_(2)SO_(4)掺量为1.2%时,其28 d抗折强度、抗压强度、表观密度最优,分别为3.8 MPa、19.5 MPa、0.98 g/cm^(3)。低品位硅藻土胶凝材料中石灰与SiO_(2)形成了水化硅酸钙(C-S-H)凝胶,Na_(2)SO_(4)复合石灰和改性硅藻土中偏高岭土反应生成地聚物,最终改善了强度。In order to improve the utilization of low grade diatomite in the field of building materials and reduce the stock.In this paper,cementation material was prepared by using lime(calcium)and Na_(2)SO_(4) synergically to activate low grade diatomite.The change of strength was studied and the mechanism of action was discussed by XRD,SEM,TEM and FT-IR.The results show that the optimum activation modification temperature of lowgrade diatomite is 850℃,and the bending strength,compressive strength and apparent density of 28 d are the best when the molar ratio of CaO to SiO_(2) is 1.4 and the content of Na_(2)SO_(4) is 1.2%,which are 3.8 MPa,19.5 MPa and 0.98 g/cm3,respectively.The low grade diatomite cementative material formed C-S-H gel with SiO_(2),and Na_(2)SO_(4) composite lime reacted with metakaolin in modified diatomite to form geopolymers,which finally improved the strength.

关 键 词：活化改性 低品位硅藻土胶凝材料 协同激发 机理研究 

分 类 号：TQ177[化学工程—硅酸盐工业]