粉煤灰基Zr改性P型分子筛对As(V)的去除

In response to the demand for the treatment of arsenic-containing wastewater pollution, this study prepared Zr-modified zeolite materials by mechanical chemical method and ion exchange method, systematically compared the difference of adsorption performance for As(V) between the two, and revealed the rules of Zr doping mode on the adsorption mechanism of materials, which provided theoretical basis for the development of efficient and stable arsenic pollution treatment materials. Zr-modified P-type zeolite was prepared from fly ash by mechanical chemical one-step synthesis method (MZr-P) and ion exchange method (IEZr-P), respectively. The adsorption performance of the materials was evaluated through pH adaptability, adsorption kinetics/thermodynamics, competitive ion interference and regeneration experiments. The quasi-second-order kinetic model (R2>0.94) indicated that the adsorption was a chemical-dominated process, and the Langmuir model showed that the maximum adsorption capacity of MZr-P reached 229.32 mg/g, which was 9.8% higher than that of IEZr-P (208.87 mg/g). Thermodynamic parameters (ΔH=79.37 kJ/mol, ΔG<0) confirmed that the adsorption was a spontaneous endothermic reaction. Due to the similar configuration of phosphate and arsenate, a significant competition (inhibition rate 23.9%) was produced, and the interference of the remaining anions was weak (<1%). After 5 times of regeneration, MZr-P still maintained 66.32% adsorption efficiency, indicating that the structure stability was excellent.