A New Innovative Low Cost Manufacturing Process to Produce Titanium

Titanium with its inherent lightweight, corrosion resistance and mechanical properties is a critical and strategic metal in civilian and defense aviation, oil extraction and processing, water purification, the general chemical industry, and would be in automotive transportation if it were more economical. The entire world’s supply of titanium as a sponge has been produced by the Kroll process for over a half century. The Kroll process is the magnesium reduction of titanium tetrachloride (TiCl4). The Kroll process is a low productivity, batch, segmented, labor intensive process in which the operations are generally carried out at separate sights resulting in high cost storage, handling and transport of the environmentally hazardous materials chlorine (Cl2), titanium tetrachloride (TiCl4), molten magnesium (Mg), and molten magnesium chloride (MgCl2). The purpose of this research was to develop a continuous low cost innovative alternative to the Kroll process that utilized the same production demonstrated Kroll chemistry to produce high value added titanium powder which eliminated the environmental hazardous materials and which meets environmental benign green manufacturing standards. The alternate processing to eliminate any storage, handling or transportation of the hazardous reactant materials consists of producing a titanium suboxide-carbon material by carbothermic reduction of an ore/TiO2 producing Ti:O:C in a stoichiometric ratio such as Ti2OC. This Ti:O:C serves as an anode feed to a MgCl2 electrolysis cell where the electrolytically generated chloride ion at the anode reacts with the Ti:O:C to in-situ produce TiCl4 that is dected to the cathode surface where the electrolytically generated Mg reduces the TiCl4 to titanium powder and regeneration of the MgCl2. Since this is a cyclic system, the feed to the cell is Ti:O:C with Ti powder continuously produced and the elimination of separately handling any hazardous materials. The Phase I program demonstrated the in-situ process in a bench scale cell on a continuous basis as well as producing a Ti-B alloy powder. An economic analysis suggests that the environmentally benign process can produce titanium powder for approximately $1.35/lb. The Phase II program is to scale-up processing with operations on a continuous basis to demonstrate commercial viability and confirm low cost processing that meets environmentally benign green manufacturing standards. The produced powder will be independently analyzed to establish ASTM grade and will be provided to outside sources to quality for direct use in powder metallurgy fabrication as well as melting for equivalency to Kroll sponge processing. The commercialization option will scale to the pilot stage to demonstrate commercial production capability, confirm environmental benign green manufacturing capability, the economics of the process, and confirm the produced titanium powder is at least equivalent to Kroll sponge quality.