铝酸三钙对氨氮的高效去除及机制研究

Efficient removal and the mechanism study of ammonia nitrogen by tricalcium aluminate

利用铝酸三钙(C3A)去除废水中的氨氮。通过批量去除实验,考察了反应时间、初始氨氮浓度、C3A投加量、温度等条件对C3A去除氨氮能力的影响。采用XRD、FT-IR及SEM对C3A和反应产物进行了结构表征。结果表明在298K时C3A对氨氮的最大去除量为155.4 mg·g-1,氨氮是通过与C3A水化过程中产生的OH-及Al(OH)-4发生中和反应被去除,产物为CaAl-Cl-LDH。本文表明C3A是一种有效的氨氮去除剂,为水泥基材料对水体污染物的去除过程及机理提供了新的认识。

Tricalcium aluminate(C3A)was used to remove ammonium from wastewater.A series of experiments have been done to investigate the conditions influencing the removal capacity of C3A,including contact time,initial ammonium concentration,dosage of C3A,and temperature.The physicochemical structure of C3A and the resultant product were characterized by X-ray diffraction(XRD),Fourier transformed infrared spectroscopy(FT-IR),and scanning electron microscope(SEM).The results revealed that the maximum removal capacity of ammonium by C3A was 155.4 mg·g-1 at 298 K.The neutralization with the hydroxyl groups and Al(OH)-4 from the hydration of C3A played an important role in ammonium removal,and the resultant product was CaAl-Cl-LDH.This work presents an efficient solution for ammonium removal by C3A,thus providing new insight into the removal process and mechanism of cement-based materials for water pollutant removal.