NSF Award
0091596
This Small Business Innovative Research Phase II project will further the development of the electrochemical chlorine purification process and conduct a pilot trial with a 0.5 square meter cell at a chlor-alkali plant. During the Phase I phase, densities as high as 0.5 A/cm2 (at room temperature) were demonstrated for this process, with a potential of less than 300 mV at the highest current density. A pilot scale MP-cell with 100 cm2-electrode area was successfully demonstrated to purify chlorine in the flow through electrode mode using anion exchange membranes. Chlorine purity at the outlet was 100%. A complete mass balance was carried out for the chlorine gas and the chloride ion. The objectives of the Phase II program include (a) study and understanding of the mechanism of chlorine reduction in concentrated hydrochloric acid, (b) investigation of catalysis of both the chloride oxidation and chlorine reduction processes in concentrated HCl, (c) building a 0.5 square meter pilot cell, and (d) conducting field trials in a chlor-alkali plant with the pilot cell. At the end of Phase II, a detailed economic analysis would have been completed to enable commercialization efforts. <br/><br/>The world chlor-alkali industry is projected to grow from the current production capacity of 42.1 million tons to 49 million metric tons in the year 2002. The total amount of tail gas to be processed is 562 million dollars through the year 2007 for a technology that replaces third stage liquefaction. The market for the second stage liquefaction is approximately 1.7 billion dollars. The U. S. market size for a low cost, energy efficient technology such as electrochemical purification is approximately 160 million dollars through 2007.
