HEAVY NON-FERROUS METALS | |
ArticleName | Kinetics of zinc, calcium and magnesium sorption from water solutions, using the amine-diacetic ionite – Lewatit TP 207 |
ArticleAuthor | Timofeev K. L., Naboychenko S. S., Lebed A. B., Akulich L. F. |
ArticleAuthorData | Research Center, “Uralelectromed” JSC, Verkhnyaya Pyshma, Sverdlovsk Oblast, Russia K. L. Timofeev, Head of a Sector L. F. Akulich, Head of Laboratory
Ural Federal University named after the first president of Russia B. N. Yeltsin, Ekaterinburg, Russia
Office of Strategic Plans, Ural Mining and Metallurgical Company, Verkhnyaya Pyshma, Russia A. B. Lebed, Chief Specialist of Metallurgy Department |
Abstract | Mine waters contain a significant amount of environmentally hazardous non-ferrous metals. It is possible to remove these metals deeply during the usage of sorption method with selective ionexchange resins. Extraction of zinc is the most complicated process, included in sorption, especially in the conditions with prevail content of harshness ions in solution. This article shows the investigation of kinetic regularities of zinc, calcium and magnesium sorption in water solutions on amine-diacetic ampholyte – Lewatit TP-207. Internal diffusion and chemical interaction are the rate-limiting steps of sorption of impurities from concentrated solutions. The activation energy varies from zinc to magnesium: 12.96 kJ/mol of Zn, 6.87 kJ/mol of Ca and 1.54 kJ/mol of Mg. Decreasing of activation energy in the “Zn – Ca – Mg” range apparently testifies about the zinc complexing with ionite amides, when ion-exchange is characteristic for calcium and magnesium. The biggest affinity of ionite to zinc is confirmed by highest capacity of resin for this cation, in comparison with calcium and magnesium: 0.5 mole/dm3 of Zn, 0.45 mole/dm3 of Ca and 0.43 mole/dm3 of Mg. More complete saturation of ionite with zinc is also confirmed by difference of initial amount of ionite and amount of ionite at the moment of sorption equilibrium. The rate of process in dilute solutions is defined by outside diffusion. Change of ionic form of resin in the Na+ – Ca2+ – H+ range leads to the decreasing of equilibrium capacity of ampholyte from 0.343 to 0.217 mmole/cm3 and decreasing of rate constant from 0.178·10–3 to 0.117·10–3 sec–1, which is connected with significant compete influence of hydrogen and calcium ions during the zinc absorption. During the simultaneous presence of cations in solution, ionite is saturated by calcium, whereupon calcium is removed by zinc. There is defined the highest selectivity of ionite, according to zinc cations, which shows the prospective application of Lewatit TP 207 resin for selective extraction of zinc from multicomponent solutions, containing hardness ions. |
keywords | Amine-diacetic ionite, sorption kinetics, selectivity, water solution, zinc, hardness ions |
References | 1. Informatsiya o produkte Lewatit MonoPlus TP-207. Lanxess Deutschland GmbH BU ION D-51369 Leverkusen. Redaktsiya 2010-11-11 (Information about the Lewatit MonoPlus TP-207 product. Lanxess Deutschland GmbH BU ION D-51369 Leverkusen. Edited since November 11, 2010). Available at: http://www.lenntech.com/products/resins/lanxess-lewatit/lanxess-lewatit-ion-resins.htm. (accessed: April 26, 2013). 7. Elkin T. E., Pasechnik V. A., Samsonov T. V. Termodinamika ionnogo obmena (Ion exchange thermodynamics). Minsk : “Nauka i Tekhnika” Publishing House, 1968. 263 p. |
Language of full-text | russian |
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