Abscheidung von Nickel und anderen Schwermetallen bei der Reinigung von Zinksulfatlösungen durch Zementieren mit Zinkstaub
type: CreativeWork
description: The industrial production of zinc sulfate employs aqueous ZnSO4 solutions. These are made from leaching zinc-containing secondary materials with sulfuric acid, with the result that they are contaminated with considerable quantities of heavy metals. These metals are removed from the solution by the process of zinc lye purification, which is performed similarly to electrolytic zinc refinement. During the cementation, other heavy metals which are nobler than zinc, e.g. lead, cadmium, cobalt, copper and nickel, are separated in the form of solid phases by adding zinc dust. Numerous experiments – both at the laboratory scale and large scale – have been performed to optimise cementation as part of zinc sulfate production, by studying the effects of parameters such as temperature, the type and concentration of impurities and the quantity of zinc dust used. These studies have employed both technical zinc sulphate solutions (working solutions) and solutions with much lower concentrations of heavy metals (pharmaceutical solutions). The present study primarily concentrated on investigating the effect of metals on the cementation of nickel, which is almost always contained in the starting solution in the large scale production of zinc sulfate. In accordance with the literature, the results showed that the cementation of nickel can be described as a first order reaction. Moreover, there was significant correlation between the rate constants for nickel cementation and the stochiometric proportions in the solution. This made it possible for the first time to eliminate two stoichiometric factors from the rate constants which unambiguously describe the concentrations in the solution. In practice, this signifies that the initial conditions in the solution are of decisive importance for the course of nickel cementation. Thus the course of nickel separation is only complete and adequately rapid when the concentrations of lead, cadmium and copper in the starting solution, at the beginni…
abstract: The industrial production of zinc sulfate employs aqueous ZnSO4 solutions. These are made from leaching zinc-containing secondary materials with sulfuric acid, with the result that they are contaminated with considerable quantities of heavy metals. These metals are removed from the solution by the process of zinc lye purification, which is performed similarly to electrolytic zinc refinement. During the cementation, other heavy metals which are nobler than zinc, e.g. lead, cadmium, cobalt, copper and nickel, are separated in the form of solid phases by adding zinc dust. Numerous experiments – both at the laboratory scale and large scale – have been performed to optimise cementation as part of zinc sulfate production, by studying the effects of parameters such as temperature, the type and concentration of impurities and the quantity of zinc dust used. These studies have employed both technical zinc sulphate solutions (working solutions) and solutions with much lower concentrations of heavy metals (pharmaceutical solutions). The present study primarily concentrated on investigating the effect of metals on the cementation of nickel, which is almost always contained in the starting solution in the large scale production of zinc sulfate. In accordance with the literature, the results showed that the cementation of nickel can be described as a first order reaction. Moreover, there was significant correlation between the rate constants for nickel cementation and the stochiometric proportions in the solution. This made it possible for the first time to eliminate two stoichiometric factors from the rate constants which unambiguously describe the concentrations in the solution. In practice, this signifies that the initial conditions in the solution are of decisive importance for the course of nickel cementation. Thus the course of nickel separation is only complete and adequately rapid when the concentrations of lead, cadmium and copper in the starting solution, at the beginni…
author: Groß, Oliver
language: ger
keywords: info:eu-repo/classification/ddc/620, Zink, Elektrochemie, Zementation <Metallurgie>, Zinksulfat, Laugung, Ingenieurwissenschaften, Zinkstaub, Grillo, Nickel, cementation, leaching, zinc sulphate, zinc dust
date published: 2007
date modified: 2026-07-30T19:43:10Z
provider: RWTH Aachen University
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Publikationsserver der RWTH Aachen University