Chlorine from Hydrogen Chloride by the Carrier Catalyst Process

Secondary Cl₂ can be recovered from HCl by technologies such as the MT-Chlor process of Mitsui Toatsu Chemicals, the Kel-Chlor 1 process of M. W. Kellogg and DuPont, and the electrolysis process of Uhde. In two U.S. patents issued in 1990 and 1991, Medalert Inc. introduced a novel process for recovering Cl₂ from HCl using a carrier catalyst that it claims recovers nearly 100% of Cl₂. The process employs a reactor system based on the design of a fluidized catalytic cracker (FCC) with two separate catalytic gas fluidized bed (CGFB) reactors. The two reactors, one for chlorination and the other for oxidation, are connected through two main tubes with a circulating flow of regenerating copper-based carrier catalyst. With the separation of the chlorination and oxidation reactions, this process ensures simplification of the downstream purification and recovery of the crude Cl₂ product. Since April 1993, Carburos Metalicos SA, a subsidiary of Air Products and Chemicals, Inc. has operated a 4-8 kg/hr capacity pilot plant using the carrier catalyst process at its Barcelona, Spain, facilities.