Determination of the maximum retention of cobalt by ion exchange in h-zeolites

Abstract

-This work aimed to determine the maximum content of cobalt that can be incorporated by ion exchange in zeolites H-USY, H-Beta, H-Mordenite, and H-ZSM-5. To reach this goal, batch isotherms at 75ºC were constructed after addition of zeolite samples in flasks filled with cobalt nitrate solution. The equilibrium data were fitted to Langmuir, Freundlich, and Tóth adsorption isotherm models. Langmuir was the best model for zeolites H-Beta, H-Mordenite, and H-ZSM-5, whereas experimental data for H-USY were better fitted to the Freundlich isotherm model. From the isotherms, it was possible to determine the maximum cobalt exchange level (q max ) that can be incorporated in each zeolite through ion exchange. In this sense, H-USY presented the highest q max value (2.40 meq/g zeol ), while H-ZSM-5 showed the lowest one (0.64 meq/g zeol ).These results also show the influence of the zeolite framework related to the channel system, pore opening, presence of cavities and secondary porosity and SiO 2 /Al 2 O 3 ratio (SAR) on the maximum capacity and behavior of cobalt ion exchange in protonic zeolites.

Synthesis and characterization of clay-based ultrafiltration membranes supported on natural zeolite for removal of heavy metals from wastewater

“…The effect of the initial concentration of Co 2+ on the rejection rate shows a decrease of the rejection with the decrease of the concentration, the obtained values are of TR CO: 65% for EF2 (2.04 mg/L) and TR CO: 32% for EF1 (0.54 mg/L). This behavior confirms the results reported by (Zola et al,2012).…”

Kinetics and Thermodynamics Studies of Cobalt (II) Adsorption onto Alumina

“…α-alumina specifically was used for this study. Various studies already have been conducted on the adsorption of heavy metals and other toxic materials from aqueous solutions using alumina [7][8][9][10].…”

Insight of the removal of nickel and copper ions in fixed bed through acid activation and treatment with sodium of clay

“…The application of various alternative materials for sorption or elimination of metals in wastewater has been investigated due to its numerous economic advantages Zola et al, 2012;Oueslati et al, 2011;Torab-Mostaedi et al, 2010;Attia et al, 2010;Yilmaz et al, 2010;Giraldo and Moreno-Piraján, 2008;Novakovic et al, 2008;Stathi et al, 2007;Ouhadi et al, 2006). The cost of clay is relatively low compared to other alternative adsorbents, including activated charcoal, natural and synthetic zeolites, and ion exchange resins.…”