果胶稳定无定形碳酸钙用于模拟含镉废水研究

Study on Pectin Stabilized Amorphous Calcium Carbonate(P-ACC)for Simulating Cadmium-Containing Wastewater

通过添加果胶作为晶型调控剂,合成果胶稳定的无定形碳酸钙(P-ACC)。利用XRD、SEM、BET吸附法、FTIR及XPS等方法对P-ACC的结构及表面性质进行了分析表征,研究了P-ACC材料对Cd^(2+)的吸附行为,考察了溶液的pH、吸附时间、吸附温度、投加剂量、Cd^(2+)初始浓度等因素对材料吸附性能的影响,探讨了吸附过程的吸附等温线、吸附动力学、吸附热力学行为。结果表明,所合成的P-ACC对Cd^(2+)的最大吸附容量为495.40 mg·g^(-1),吸附过程符合Langmuir吸附等温式和准二级动力学模型;吸附热力学分析表明,吸附是一个自发吸热的过程,所制备的P-ACC对Cd^(2+)具有良好的吸附性能,能在2 h内将初始浓度为2.0 mg·L^(-1)的Cd^(2+)完全去除,为水体中重金属镉污染废水的环境修复提供一个新的研究思路。

The amorphous calcium carbonate(P-ACC)with pectin stability was synthesized by adding pectin as a crystal form regulator.The structure and surface properties of the materials were characterized by the adsorption method of XRD,SEM,BET,FTIR,and XPS.The adsorption behavior of the prepared materials on Cd^(2+)was investigated.The pH,adsorption time,adsorption temperature,the effects of dosage,and initial concentration of Cd^(2+)on the adsorption properties of the materials were investigated.The adsorption isotherms,adsorption kinetics,and adsorption thermodynamic behaviors of the adsorption process were discussed.The results show that the maximum adsorption capacity of the synthesized P-ACC for Cd^(2+)is 495.40 mg·g^(-1),and the adsorption process conforms to the Langmuir adsorption isotherm and pseudo-second order kinetic model.The adsorption thermodynamic analysis showed that the adsorption process was a spontaneous endothermic process,and the prepared P-ACC had good adsorption performance for Cd^(2+),and can completely remove Cd^(2+)with an initial concentration of 2.0 mg·L^(-1)within 2 hours,which provided a new research idea for the environmental remediation of heavy metal cadmium-contaminated wastewater in water.