不同Ca/P摩尔比碳羟基磷灰石对Cu^2＋的吸附特性

Adsorption Characteristic of Carbonate Hydroxylapatite for Cu^(2+) from Aqueous Solution at Different Ca/P Molar Ratios

利用废弃蛋壳为原料、尿素为添加剂,合成不同Ca/P摩尔比的碳羟基磷灰石(CHAP)用于吸附水中Cu2+,利用红外光谱、扫描电子显微镜、X射线能谱测试技术对CHAP样品表面化学进行了表征,考察了环境因子pH值、温度对CHAP吸附Cu2+的影响。结果表明,通过改变尿素用量可以增加CHAP的Ca/P,提高其比表面积,Ca/P越高的CHAP,吸附能力越强。Ca/P为1.80的CHAP,在pH=7、温度40℃、反应时间为60min时,其对Cu2+吸附量高达37.66mg/g。随着CHAP的Ca/P比增大,CHAP对Cu2+吸附的固相-水相分配系数也增大,对吸附量增大很有利。

The adsorption of Cu^2＋ from aqueous solution by home-made carbonate hydroxylapatite （CHAP） synthesized from abandoned eggshell with urea as the addititive was characterized by FT-IR, SEM and EDS. Factors that might influence the adsorption performance were investigated, including pH values, temperature and adsorption period in aqueous solution. The results show that the molar ratio of Ca/P in CHAP and the specific surface area increased with the amount of urea, and the absorption capacity became greater because Ca/P ratio of CHAP was higher. Absorption capacity of CHAP （ Ca/P ratio, 1.80） for Cu^2＋from aqueous solution reached 37.66 mg/g when pH was 7, the temperature was 40 ℃, the reaction time was 60 rain. The distribution coefficient between solid phase and water increased with the increase of Ca/P ratio of CHAP, which improves the absorption capacity..