Study on Preparation and Mechanism of Clinker-Free Cementing Material of Low Grade Diatomite
In order to improve the utilization of low grade diatomite in the field of building materials and reduce the stock.In this paper,cemen-tation material was prepared by using lime(calcium)and Na2SO4 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 low-grade 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 SiO2 is 1.4 and the content of Na2SO4 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 SiO2,and Na2SO4 composite lime reacted with metakaolin in modified diatomite to form geopolymers,which finally improved the strength.
activation modificationlow-grade diatomite cementing materialsynergistic excitationmechanism research
NETL
NSTL
万方数据
