Microwave Synthesis of Rare Earth Adsorbent

The new-style Ce-modified zeolite adsorbent (CZA) was prepared by modifying 90 ¿m zeolite with cerium. Using the microwave synthesis technology instead of the conventional roasting technology in the absorbent preparation process. The adsorption capacity of microwave CZA for ammonia nitrogen and phosphate were 6.25 mg/g and 18.2 mg/g respectively. These data correlated well with Freundlich adsorption isotherm model. The value of the parameter K
_f
and n of the microwave CZA are bigger than the roasting CZA, which showed that the adsorption capacity of the microwave CZA is better than the roasting CZA. The removal efficiency of the ammonia nitrogen and phosphate can reach 80.0% and 99.5% respectively under the following conditions: the quantity of microwave CZA was 1 g/L, the pH value of the solution was 4~6 and the contact time was 2.5 h. Adsorption capacity of ammonia nitrogen and phosphate would be descended less than 15% and 8% respectively after the absorbent regenerated 10 times, which meant a good stability of microwave CZA.