Date of Graduation

2017

Document Type

Dissertation

Degree Type

PhD

College

Statler College of Engineering and Mineral Resources

Department

Chemical and Biomedical Engineering

Committee Chair

Alfred Stiller

Committee Co-Chair

Robin Hissam

Committee Member

Charter Stinespring

Committee Member

David Walker

Committee Member

Scott Wayne

Abstract

Calcium carbide was historically used to reduce potassium metal from potassium fluoride as described in a 1922 patent. This was prior to the discovery of electrolytic synthesis, which replaced the carbide process in less than five years. A byproduct of this process was elemental carbon. This carbon was unanalyzed at the time. The object of this research was to analyze carbon produced in reactions similar to this and to determine if this reaction could be carried out under milder conditions. It was found that the reaction is part of a family of reactions, and would proceed with a number of other salts, including zinc chloride, stannous chloride, and stannous fluoride. The carbon produced via molten salt reactions was irregular, and primarily amorphous. The reactions could take place in a solvent at room temperature. Carbon produced via solvent-phase reactions was more orderly and primarily graphitic. Finally, the reactions could take place in a galvanic cell, separating the reactions into two half reactions. This configuration had numerous benefits: reaction rates could be measured via current, metallic byproducts are produced in a separate cell from carbon simplifying purification, and morphology of carbon was more regular. Almost no amorphous carbon was produced in this configuration. The carbon produced in solvent-phase reactions, both simple solvent-phase and galvanic cell, showed unusual morphology. Highly ordered, hexagonal crystals were found throughout all solvent-phase reaction products. These crystals were shown to be highly ordered via Raman spectroscopy. Future work should be focused on synthesizing carbides to reduce contaminant concentration, synthesizing commercially unavailable carbides, and attempts to isolate and exfoliate hexagonal crystals to graphene.

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