title: Removal of ammonium ion from aqueous solution by natural Turkish (Yildizeli) zeolite for environmental quality.
abstract: The purposes of this study were to investigate the removal efficiency of ammonium (NH(4)(+)) ion from aqueous solution using the natural Turkish (Yildizeli) zeolite and to characterize equilibrium isotherms. Experiments were carried out using batch method as a function of the solution pH, shaking time, dosage of adsorbent, and temperature. All these factors affected NH(4)(+) ion removal from aqueous solution. Equilibrium modelling data were fitted to linear Langmuir and Freundlich models. Dubinin-Redushckevich (D-R) isotherm was applied to describe the nature of ion exchange of NH(4)(+) and found that it occurred physically. Thermodynamics parameters such as change in free energy (DeltaG degrees ), enthalpy (DeltaH degrees ) and entropy (DeltaS degrees ) were also calculated. These parameters confirmed that ion exchange of NH(4)(+) by the zeolite was feasible, spontaneous and exothermic in nature. Based on the results, it can be concluded that the natural Turkish (Yildizeli) zeolite is suitable for the removal of NH(4)(+) ions in wastewater treatments and agricultural purposes to in terms of sustainability of environmental quality.
authors.affiliation: Department of Soil Science, Faculty of Agriculture, University of Gaziosmanpasa, 60240 Tokat, Turkey. kadirs@gop.edu.tr
authors.forename: Kadir
authors.initials: K
authors.lastname: Saltali
authors.forename: Ahmet
authors.initials: A
authors.lastname: Sari
authors.forename: Mehmet
authors.initials: M
authors.lastname: Aydin
mesh_terms: D000327:Adsorption; D006863:Hydrogen-Ion Concentration; D000644:Quaternary Ammonium Compounds / Q000737:chemistry*; D013696:Temperature; D013816:Thermodynamics; D014421:Turkey; D014865:Waste Disposal, Fluid / Q000379:methods*; D014873:Water Pollutants / Q000737:chemistry*; D017641:Zeolites / Q000737:chemistry*
chemical_list: D000644:Quaternary Ammonium Compounds; D014873:Water Pollutants; D017641:Zeolites