title: Removal of ammonium ions by laboratory-synthesized zeolite linde type A adsorption from water samples affected by mining activities in Ghana.
abstract: Ammonium ion adsorption by laboratory-synthesized zeolite (linde type A; LTA) was investigated in batch kinetics experiments. Synthesized zeolite LTA was characterized by X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, thermogravimetric analysis, Fourier transform infrared spectroscopy and particle size analysis. Water samples were taken from the Nyam and Tano rivers in Ghana, and 0.8 g of zeolite was added to 100 ml portions of each sample. Portions of the samples were withdrawn every 30 min for 150 min and the concentration of ammonia in each sample was determined. The removal efficiency of zeolite LTA was evaluated by retrieving the zeolite from the water samples and adding to a fresh sample to repeat the process. Equilibrium data were fitted by Langmuir and Freundlich isotherms. Maximum adsorption capacities were 72.99 mg g(-1) for samples from the River Nyam and 72.87 mg g(-1) for samples from the River Tano. The equilibrium kinetic data were analysed using adsorption kinetic models: pseudo-first order and pseudo-second order kinetic models. Linear regression was used to estimate the adsorption and kinetic parameters. The results showed that the adsorption followed pseudo-second order kinetics and suggest that zeolite LTA is a good adsorbent for the removal of nitrogen ammonia from water.
authors.affiliation: Department of Physics, Kwame Nkrumah University of Science and Technology, University Post Office, Private Mail Bag, Kumasi, Ghana E-mail: bkwakye-awuah.cos@knust.edu.gh.
authors.forename: Bright
authors.initials: B
authors.lastname: Kwakye-Awuah
authors.affiliation: Department of Physics, Kwame Nkrumah University of Science and Technology, University Post Office, Private Mail Bag, Kumasi, Ghana E-mail: bkwakye-awuah.cos@knust.edu.gh.
authors.forename: Linus Kweku
authors.initials: LK
authors.lastname: Labik
authors.affiliation: Department of Physics, Kwame Nkrumah University of Science and Technology, University Post Office, Private Mail Bag, Kumasi, Ghana E-mail: bkwakye-awuah.cos@knust.edu.gh.
authors.forename: Isaac
authors.initials: I
authors.lastname: Nkrumah
authors.affiliation: School of Applied Sciences, University of Wolverhampton, Wulfruna Street, Wolverhampton WV1 1LY, United Kingdom.
authors.forename: Craig
authors.initials: C
authors.lastname: Williams
mesh_terms: D000327:Adsorption; D005869:Ghana; D008855:Microscopy, Electron, Scanning; D008906:Mining; D010316:Particle Size; D000644:Quaternary Ammonium Compounds / Q000302:isolation & purification*; D045483:Rivers; D013052:Spectrometry, X-Ray Emission; D017550:Spectroscopy, Fourier Transform Infrared; D013818:Thermogravimetry; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*; D018508:Water Purification / Q000379:methods*; D014961:X-Ray Diffraction; D017641:Zeolites / Q000138:chemical synthesis*
chemical_list: D000644:Quaternary Ammonium Compounds; D014874:Water Pollutants, Chemical; D017641:Zeolites