工业氟硅酸改性硫酸铝基无碱液体速凝剂性能的研究  

Study on the performance of industrial fluorosilicic acid modified aluminum sulfate based alkali free liquid accelerator

作　　者：朱芳芳 刘远 杨林[1] 张远永 ZHU Fangfang;LIU Yuan;YANG Lin;ZHANG Yuanyong(School of Chemistry and Chemical Engineering,Guizhou University,Guiyang 550025,China;Guizhou Tianwei Building Materials Technology Co.,Ltd.,Guiyang 550009,China)

机构地区：[1]贵州大学化学与化工学院,贵州贵阳550025 [2]贵州天威建材科技有限公司,贵州贵阳550009

出　　处：《应用化工》2024年第9期2095-2099,共5页Applied Chemical Industry

基　　金：贵州省科技计划项目(黔科合平台人才[2019]5409号);校企合作项目(TW2021111501号)。

摘　　要：以硫酸铝作为主料,复配三乙醇胺、碳酸锂等物料,制备无碱液体速凝剂,再将工业氟硅酸作为改性组分,考察了不同工业氟硅酸掺量下硫酸铝无碱速凝剂对P·O 42.5普通硅酸盐水泥的凝结时间、抗压强度性能的影响。采用XRD、SEM和TG-DTG分析探究试样水化产物的物相组成及微观形貌,进一步探讨了掺改性组分硫酸铝速凝剂的水泥水化反应进程及改性组分的作用机理。结果表明,工业氟硅酸掺入速凝剂中,能显著缩短水泥的凝结时间。当速凝剂中工业氟硅酸掺量为10%时,水泥凝结时间达到最小值,初凝和终凝时间分别为1.67 min和4.28 min。随着速凝剂中不同掺量工业氟硅酸的加入,砂浆的1 d抗压强度以及28 d抗压强度先增大后减小,抗压强度在工业氟硅酸掺量为6%时达到最大值,1 d和28 d强度分别为12.4 MPa和48.4 MPa。对比未掺入工业氟硅酸的速凝剂,加入工业氟硅酸后水泥浆体会消耗CH成更多针棒状AFt,且加快C_(3)S水化,形成C—S—H凝胶。但是,当工业氟硅酸掺量过量时,生成的CaF_(2)沉淀物会抑制水化反应,影响砂浆1 d的抗压强度形成。The aluminum sulfate as the main material,compounded with materials such as triethanolamine and lithium carbonate,to prepare an alkali free liquid accelerator.Then,industrial fluorosilicic acid is used as a modified component to investigate the effect of aluminum sulfate alkali free accelerator on the setting time and compressive strength performance of P•O 42.5 ordinary portland cement at different industrial fluorosilicic acid dosages.XRD,SEM,and TG-DTG were used to analyze the phase composition and microstructure of the hydration products of the sample,and further explore the process of cement hydration reaction with the addition of modified component aluminum sulfate accelerator and the mechanism of action of the modified component.The results show that the addition of industrial fluorosilicic acid into the accelerator can significantly shorten the setting time of cement.When the industrial fluorosilicic acid content in the accelerator is 10%,the cement setting time reaches the minimum value,with initial and final setting times of 1.67 min and 4.28 min,respectively.With the addition of different amounts of industrial fluorosilicic acid in the accelerator,the 1 d compressive strength and 28 d compressive strength of the mortar first increase and then decrease.The compressive strength reaches its maximum when the industrial fluorosilicic acid content is 6%,and the 1 d and 28 d strengths are 12.4 MPa and 48.4 MPa,respectively.Compared with the accelerator without industrial fluorosilicic acid,after adding industrial fluorosilicic acid,the cement slurry will consume CH into more needle bar AFt,and accelerate the hydration of C_(3)S to form C—S—H gel.However,when the industrial fluorosilicic acid content is excessive,the generated CaF_(2) precipitate will inhibit the hydration reaction and affect the formation of the compressive strength of the mortar for 1 d.

关 键 词：速凝剂 改性组分 工业氟硅酸 作用机理 

分 类 号：TQ09[化学工程] TQ074TQ444