Processes for working-up an aqueous fluosilicic acid solution

South African Journal of Science


 
 
Field Value
 
Title Processes for working-up an aqueous fluosilicic acid solution
 
Creator Toure, Alpha O. Sambe, Falilou M. Koita, Démo Diop, Codou M.G. Sock, Oumar
 
Subject Chemical and Environmental Engineering caustic soda; caustification; ethanol; precipitation; sodium chloride
Description Aqueous fluosilicic acid solutions were once considered to be only adverse by-products of phosphoric acid production, which required treatment to prevent ecosystem destruction when discharged into the sea. However, a range of chemicals can be generated by the transformation of this industrial waste product. Through experiments undertaken in the laboratory, we have shown the possibility of caustic soda production. Volumetric analysis showed caustic soda to be present as a 6% – 7% solution with yields of about 70% – 80% by weight. Two processes were investigated for the caustification of sodium fluoride, using different precipitates: sodium chloride and ethanol and are described by modelling caustification curves. The activation energies of precipitation determined by semi-empirical correlations showed that precipitation by ethanol (EA = 933.536 J/mol) was more successful than precipitation by sodium chloride(EA = 7452.405 J/mol). Analyses performed on the precipitates highlighted compositions that are essential and useful constituents in the cement industry.
 
Publisher AOSIS
 
Contributor
Date 2012-11-02
 
Type info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion — —
Format application/pdf text/html application/octet-stream text/xml
Identifier 10.4102/sajs.v108i11/12.919
 
Source South African Journal of Science; Vol 108, No 11/12 (2012); 5 pages 1996-7489 0038-2353
 
Language eng
 
Relation https://journals.sajs.aosis.co.za/index.php/sajs/article/view/919/1522 https://journals.sajs.aosis.co.za/index.php/sajs/article/view/919/1523 https://journals.sajs.aosis.co.za/index.php/sajs/article/view/919/1524 https://journals.sajs.aosis.co.za/index.php/sajs/article/view/919/1533 https://journals.sajs.aosis.co.za/index.php/sajs/article/downloadSuppFile/919/2667
 
Coverage — — —
Rights Copyright (c) 2012 Alpha O. Toure, Falilou M. Sambe, Démo Koita, Codou M.G. Diop, Oumar Sock https://creativecommons.org/licenses/by/4.0