Catalyst Distribution Strategies in Fixed-Bed Reactors for Bromine Production

Abstract

The gas-phase oxidation of hydrogen halides to the corresponding halogens has gained industrial relevance following the recent discovery of active and stable heterogeneous catalysts based on RuO2 and CeO2. These developments originated from the need of polyurethane and polycarbonate producers to recycle the large amounts of byproduct HCl to Cl2 for further use in the phosgenation step. More recently, the catalyzed HBr oxidation to Br2 has been regarded as an enabling technology for bromine-mediated alkane functionalization processes. The highly exothermic and corrosive character of these reactions, especially HBr oxidation, requires particular precautions regarding temperature control to guarantee stable and safe operation in connection with the catalyst, the reactor, and ultimately the plant. Adopting experimental data available in the literature and considering model simplifications, we rationalize effective strategies to recover bromine, which involve simulations of staged RuO2/TiO2 and CeO2/ZrO2 catal...