C (A) S H对氯离子的吸附性能研究

Investigation on Adsorption Behavior of Chloride by Calcium Silicate Hydrate and Calcium Aluminum Silicate Hydrate

关键词:  水化硅铝酸钙  氯离子吸附  傅里叶红外光谱  扫描电镜  钙硅比  铝硅比

Key words:  C A S H  adsorption of chloride  Fourier transform infrared spectroscopy(FTIR)  scanning electron microscopy(SEM)  calcium silicate ratio  aluminum silicate ratio

摘要:

通过化学沉淀法合成了不同钙硅比(nCa/nSi=08~20)和不同铝硅比(nAl/nSi=0~06)的水化硅酸钙(C S H)和水化硅铝酸钙(C A S H),并以氯盐溶液浸泡结合离子色谱仪(IC)研究了这2种水化产物对氯离子的吸附特性;同时结合傅里叶红外光谱法(FTIR)和扫描电镜(SEM)研究了钙硅比、铝硅比对C (A) S H结构及其微观形貌的影响.结果表明:随着浸泡液浓度的增大,C S H和C A S H对氯离子的吸附量均逐渐增大,吸附曲线符合Freundlich吸附模型;钙硅比和铝硅比影响着C (A) S H的聚合度和结构,C (A) S H的氯离子吸附能力随钙硅比有先升高后降低的趋势;随着铝硅比的增大,尤其是铝硅比超过02之后,C A S H吸附氯离子的能力明显降低.

Abstract:

Hydrated calcium silicate(C S H)and hydrated calcium aluminosilicate(C A S H) with different calcium silicon ratio(nCa/nSi=0820) and aluminum silicon ratio(nAl/nSi=006) were synthesized by chemical precipitation method, and the adsorption capacity of chloride ions were studied by ion chromatography(IC) after immersion in chloride solution. The effects of calcium silicon ratio and aluminum silicon ratio on C (A) S H structure and microscopic morphology were studied by Fourier transform infrared spectroscopy(FTIR) and scanning electron microscopy(SEM). The results show that the adsorption capacity of chloride are increased with the increase of the concentration of chloride solution, which conform to Freundlich adsorption model. Both calcium silicon ratio and aluminum silicon ratio affect the polymerization degree and structure of C (A) S H. Chloride adsorption capacity of C (A) S H increases first and then decreases with calcium silicon ratio. With the increase of aluminum silicon ratio, especially beyond 02, chloride adsorption capacity of C (A) S H decreases significantly.