Ammonia-nitrogen and phosphates sorption from simulated reclaimed waters by modified clinoptilolite.
This paper presents the investigation of the ammonia-nitrogen and phosphates sorption from simulated reclaimed wastewater by modified clinoptilolite. The results showed that the modified clinoptilolite has a high sorption efficiency and removal performance. The ammonia-nitrogen and phosphates removal rate of the modified clinoptilolite reached to 98.46% and 99.80%, respectively. The surface of modified clinoptilolite became loose and some pores appeared, which enlarged the specific surface area; the contents of Na and Fe increased, and the contents of Ca and Mg decreased. The modified clinoptilolite possesses rapid sorption and slow balance characteristics and ammonia-nitrogen and phosphates sorption is more consistent with the Langmuir isotherm model. The adsorption kinetics of ammonia-nitrogen and phosphates follows the Elovich adsorption dynamics equation, which describes the sorption of ammonia-nitrogen and phosphates in aqueous solution as mainly a chemical sorption. Results from the thermodynamics experiment involving ammonia-nitrogen and phosphates sorption reveal that the process is a spontaneous and endothermic process, and is mainly driven by entropy effect.
School of Civil and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China.
Hanxin
H
Huo
Hai
H
Lin
Yingbo
Y
Dong
Huang
H
Cheng
Han
H
Wang
Lixia
L
Cao
D000327:Adsorption; D000641:Ammonia / Q000737:chemistry*; D002712:Chlorides / Q000737:chemistry; D005290:Ferric Compounds / Q000737:chemistry; D006358:Hot Temperature; D009584:Nitrogen / Q000737:chemistry; D010710:Phosphates / Q000737:chemistry*; D012965:Sodium Chloride / Q000737:chemistry; D014865:Waste Disposal, Fluid / Q000379:methods*; D062065:Wastewater; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D017641:Zeolites / Q000737:chemistry*
D000641:Ammonia; D002712:Chlorides; D005290:Ferric Compounds; D009584:Nitrogen; D010710:Phosphates; D012965:Sodium Chloride; D062065:Wastewater; D014874:Water Pollutants, Chemical; D017641:Zeolites; C083175:clinoptilolite; C024555:ferric chloride