The Influence of Hydrochloric Acid on the Zinc Extraction From Flux Skimming

Abstract

This paper presents experimental results obtained by agitation leaching of hazardous waste sample -flux skimming. Such flux is formed by Zn(OH)Cl and NH 4 Cl phases. Distilled water and water solutions of hydrochloric acid were selected as a leaching media. The aim of this study was to determine optimal conditions of zinc extraction into the solution. The apparent order of reaction with regard to the initial HCl concentration in the leaching solution is n=0.18 in the concentration range from 0.01 mol.dm -3 to 0.25 mol.dm -3 . The obtained results also indicate that the temperature does not significantly affect zinc extraction. The value of apparent activation energy was estimated to E a =3.985 kJ.mol -1 . Optimal liquid to solid ratio L:S=80 for both used leaching media was also determined experimentally as well as the stirring rate at 200 rpm.

Production of zinc oxide from hazardous waste - Sal Ammoniac Skimming

“…2 a-d), the effect of leaching medium, temperature and time of the extraction of zinc in the solution were studied. The results were already published by authors in literature [15,16].…”

“…The Zn(OH)Cl phase, according to the source, may be produced by heating hydrated zinc chloride to form Zn(OH)Cl according to the following equation (1) [15,16]: (1)…”

“…Leaching of Zn(OH)Cl in an aqueous solution of HCl may be carried out according to the following reaction (2) [15,16]. The value of ΔG 0 of the mentioned equation was calculated at 20°C.…”

“…2b). Subsequently, a solution containing Zn 2+ ions was applied in the process of precipitation of zinc from the solution [15,16].…”

Wastewater Treatment from Galvanization Industry with Zinc recovery

“…Galvanization with Zinc is a commonly used method to increase the corrosion resistance of steel (Zn galvanizing) [1,2]. The process entails the following steps: 1) degreasing, 2) pickling with hydrochloric acid in order to remove iron oxides such as rust or scale, 3) rinsing with water and fluxing so as to chemically activate the surface and enhance the reaction with zinc.…”