Removal of ammoniacal nitrogen from aqueous solution using clinoptilolite as adsorbent

Abstract

Removal of ammoniacal nitrogen from aqueous solution using clinoptilolite was investigated by influence factors of particle size, initial concentration, contact time, and adsorbent dosage. One-factor-at-a-time (OFAT) approach was used for experimental design to obtained maximized ammoniacal nitrogen removal and rate of ammoniacal nitrogen adsorption of clinoptilolite from aqueous solutions. Adsorption isotherm then was analyzed by using Langmuir and Freundlich model to determine the relationship between adsorption and adsorbate surface. The results show that smaller clinoptilolite particle size gives a higher rate of removal of ammoniacal nitrogen and adsorption capacity which are 66.67% and 9.39 mg/g respectively. The initial concentration of 100 mg/l gives better removal and adsorptions with a higher contact time which is at 60 min. Based on the comparison of data, the rate of ammoniacal nitrogen adsorption by clinoptilolite was well-fitted with Freundlich isotherm instead of Langmuir isotherm. The study found that clinoptilolite with the smallest particle size was more efficient in removing ammoniacal nitrogen and procuring a high rate of ammoniacal nitrogen adsorption.