Chloride Ion Modified By Calcined Hydrotalcite In Cement-based Materials Study On Adsorption

Chlorine salt erosion is one of the important reasons leading to the erosion and destruction of buildings.Due to its great damage,the destruction mechanism is complex,and the damage to society is serious.Especially in the northwest saline area,the phenomenon of chloride salt corrosion is particularly serious,and the traditional method to prevent the chloride salt corrosion is to improve the density of the concrete,and apply anti-rust paint on the surface of the steel bar,which has certain limitations.With the development of building materials science,hydrotalcite,as an anionic clay,has a good layered structure.After calcination modification,hydrotalcite has good adsorption properties.Therefore,in this paper,hydrotalcite is used as an adsorption material to study its cement Adsorption properties of chloride ions in base materials.In this paper,the hydrotalcite is physically modified by calcined to improve its adsorption capacity.To study the adsorption properties of chloride ions in cement-based materials,treat hydrotalcite as a material for adsorbing chloride ions,and study the adsorption effect of calcined modified hydrotalcite on chloride ions in cement-based materials.The effects of calcined hydrotalcite on the mechanical properties of the mortar,the adsorption capacity of the calcined hydrotalcite on the chloride ion,and the influence of the chloride ion on the zeta potential and electrical conductivity of the hydrotalcite are developed.The effects of calcined hydrotalcite at different temperatures and different dosages on the zeta potential and electrical conductivity of sodium chloride were studied,and the hydrotalcite was characterized and analyzed by SEM,FTIR,XRD and other methods to study the calcined modified hydrotalcite on mortar influence of mechanical properties and chloride ion content in mortar samples after immersion in sodium chloride solution.The conclusions of the study are as follows:(1)The hydrotalcite after being calcined at 500 ℃ for 4 hours has the best performance of adsorbing chloride ion.After calcining,the hydrotalcite loses its characteristic diffraction peak,and can absorb chloride ion in sodium chloride solution to realize the structural reconstruction.(2)Compared with non-calcined hydrotalcite mortar,2%,4%,6% calcined hydrotalcite can improve the early mechanical properties of the mortar.When the amount of hydrotalcite does not exceed 4%,and the calcination temperature does not exceed 500 ℃,the calcined hydrotalcite mortar with different amounts will not affect its 28-day mechanical properties.(3)Without affecting the 28-day mechanical properties of the mortar,the calcination temperature of hydrotalcite is 500 ℃ with the dosage of 2%,4%,6%,2% of the calcined hydrotalcite mortar has the best chloride ion adsorption performance.Compared with the control group,the chloride ion adsorption capacity increased by 92%.The experimental research in this paper will provide useful exploration for the application of hydrotalcite in cement-based materials.As a new type of green and non-polluting material,hydrotalcite has played a certain role in the resistance of cement-based materials to chloride ion to a certain degree,it provides a reference for solving chloride salt corrosion.