Discipline: Technology and Engineering
Subcategory: Pollution/Toxic Substances/Waste
Maci Joseph - Howard University
Co-Author(s): Alpha O. Toure and Cheikhou Kane, University of Cheikh Anta Diop of Dakar, Dakar, Senegal, Africa
Fluosilicic acid (FSA) is a fluoridation agent that is produced as a byproduct of phosphoric acid manufacturing for fertilizers. Presently, there is no common treatment of this industrial wastewater for the manufacturer Industries Chimiques du Sénégal. As a result, the acid is being wasted into the water body on the coast of the West African country. Treatment of the waste can lead to the production of more valuable chemical processes for other industries. Neutralization of fluosilicic acid in a 29 weight-% solution of water with calcium hydroxide produces a filter cake of calcium fluoride, silica and water. After filtration and drying of the liquid phase, trials showed an inverse proportionality between humidity and reaction time as well as humidity and mass fraction of fluosilicic acid in solution. The cake produced at 10% excess, 1 hour reaction time and 29 weight-% FSA solution showed a chemical composition of 33.8% calcium, 31.6% fluorine and 10.8% silicon: consistent with the proposed chemical reation. It was concluded that the dry cake would be an efficient material for the production of white cement.
Funder Acknowledgement(s): This study was supported, in part, by a grant from the National Science Foundation awarded to Lorraine Fleming, Wayne Patterson, and Mohamed Chouikha, Principal and Co-Principal Investigators of the Global Education, Awareness and Research Undergraduate Program (GEARUP), Howard University, Washington, DC. As well as Alpha Toure and Chiekhou Kane of the University of Cheikh Anta Diop of Dakar, Ecole Supérieure Polytechnique (ESP), Department of Chemical Engineering and Applied Biology, Laboratory of Electrochemistry and Membrane Process, Dakar, Senegal.
Faculty Advisor: Alpha Toure, alpha2re@gmail.com
Role: In this research, I was responsible for the background research, the basics of the experimentation, interpretation of the results and the writing of the research paper.