Single and multicomponent ion exchange of silver, zinc and copper on zeolite 4a

Download

index.pdf

Date

2008

Author

Ay, Hale

Metadata

Show full item record

Item Usage Stats

276
views

113
downloads

Ion exchange of heavy metals with zeolites is important in terms of different application areas. Industrial wastewater treatment and antibacterial applications are two essential areas that have taken great attention. While silver, zinc and copper are well known for their toxicity, they are also used as antibacterial agents in zeolites. The objective of this study is to investigate the single and multicomponent ion exchange behavior of zeolite 4A for silver, zinc, copper and sodium ions. For this purpose Ag+-Na+, Zn2+-Na+, Cu2+-Na+ binary systems and Ag+-Zn2+-Na+, Ag+-Cu2+-Na+, Cu2+-Zn2+-Na+ ternary systems were investigated in batch systems at 25°C and 0.1 N. Binary ion exchange isotherms indicate that zeolite 4A has high selectivity for silver, zinc and copper with respect to sodium. All exchange isotherms lie above the diagonal over the whole range. Using the equilibrium data, the thermodynamic analysis of the binary systems were carried out. The thermodynamic equilibrium constants and the standard free energies of exchange were calculated as 340.9 and -14.5 kJ/mol for silver-sodium system, 40.5 and -4.6 kJ/mol for zinc-sodium system, and 161.2 and -6.3 kJ/mol for copper-sodium system, respectively. From these values, selectivity sequence of zeolite 4A was determined as Ag+ > Cu2+ > Zn2+. This selectivity sequence was also verified by the results of ternary ion exchange experiments. The experimental data were compared with the Langmuir and Freundlich isotherms. While Freundlich model gives a better correlation for Ag+-Na+ and Zn2+-Na+ exchange, Langmuir model represents a better fit to the experimental data of Cu2+-Na+ exchange.

Subject Keywords

Chemical engineering., Chemistry.

URI

http://etd.lib.metu.edu.tr/upload/2/12609882/index.pdf
https://hdl.handle.net/11511/17957

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Impact modified polystyrene based nanocomposites Yeniova, Canan Esma; Yılmazer, Ülkü; Department of Chemical Engineering (2009) Polystyrene, PS, is a preferable polymer in industry, but, its brittle characteristic restricts its utilization. The aim of this study is to improve the impact strength of PS by the help of elastomeric materials SEBS-g-MA and E-BA-GMA. In order to prevent the reduction in the tensile strength of the materials, three different types of organic montmorillonites, MMT, (Cloisite® 30B, 25A and 15A) were used as fillers. Nanocomposite preparation was performed in a co-rotating twin screw extruder. Initially elast...
Study of adsorption characteristics of long chain alkyl amine and petroleum sulfonate on silicates by electrokinetic potential, microflotation, FTIR, and AFM analyses ÖZÜN, Savaş; Atalay, M. Umit; Demirci, Şahinde (Informa UK Limited, 2019-05-19) The long-chain alkyl amines and petroleum sulfonates are mostly used to remove unwanted minerals from feldspar ores in acidic pHs. In this study, their adsorption characteristics on pure albite and quartz were investigated by electrokinetic potential measurements, microflotation tests, Fourier transform infrared spectroscopy, and atomic force microscopy studies. According to the results, amine had strong influence on zeta potentials of both albite and quartz turning them positive and resulting over 90% flot...
Zinc borate production in a batch reactor Gürhan, Deniz; Eroğlu, İnci; Department of Chemical Engineering (2005) Zinc borate is a flame retardant additive used in polymers, wood applications and textile products. There are different types of zinc borate having different chemical composition and structure. In this study, the production of zinc borate that had the molecular formula of 2ZnO.3B2O3.3,5H2O was studied. The aim of this study was to investigate the effects of reaction parameters on the properties of zinc borate that had been synthesized by the reaction of boric acid and zinc oxide at the existence of the seed...
Chemical vapor deposition of boron carbide Karaman, Mustafa; Özbelge, Önder; Department of Chemical Engineering (2007) Boron carbide was produced on tungsten substrate in a dual impinging-jet CVD reactor from a gas mixture of BCl3, CH4, and H2. The experimental setup was designed to minimise the effect of mass transfer on reaction kinetics, which, together with the on-line analysis of the reactor effluent by FTIR, allowed a detailed kinetic investigation possible. The phase and morphology studies of the products were made by XPS, XRD,micro hardness and SEM methods. XPS analysis showed the existence of chemical states attrib...
Sensitization of sol-gel derived titania-silica photocatalytic thin films with ascorbic acid Yılmaz, Emre; Karakaş, Gürkan; Department of Chemical Engineering (2012) The photocatalytic activity of semiconductor metal oxides can be improved by the addition of sensitizer which enhances the band gap by considerable red shift of the absorption edge of semiconductor. In the present study, the effect of ascorbic acid as sensitizer on the photocatalytic activity of titania-silica binary mixtures was studied. The SiO2-TiO2 mixtures having 50wt%Ti:Si composition were prepared with sol-gel method. The surface area and porosity of the samples were modified by using various amounts...

Citation Formats

H. Ay, “Single and multicomponent ion exchange of silver, zinc and copper on zeolite 4a,” M.S. - Master of Science, Middle East Technical University, 2008.