Natural Zeolite Adsorption for Ammonia From Low Concentration Wastewater: Study on Influencing Factors

Water pollution relating to ammonia nitrogen is one of the prevalent environmental problems. Adsorption is an effective method for ammonia nitrogen removal. This paper studied the influencing factors of ammonia adsorption onto natural zeolite, including temperature; zeolite particle size, zeolite dosage, and ammonia initial concentration. In the range of 5 similar to 15 degrees C, temperature was not an important influencing factor for ammonia adsorption. Higher adsorption rate could be obtained by zeolite with smaller particle size. When the dosage of natural zeolite grew from 6 g to 16 g, the adsorption rate increases gradually. As the ammonia initial concentration increased from 5 mg/L to 50 mg/L, the adsorption rate exhibited a slight increase and then a significant decline. Ammonia nitrogen adsorption kinetics was characterized of fast initial absorption and slow equilibration, with an optimal time of 2.5 h.