Characteristics of Bunsen reaction using HIx solution (HI–I2–H2O) in a co-current flow mode for the sulfur-iodine hydrogen production process

Abstract For integrated operation of the sulfur-iodine (SI) hydrogen production process, a HI x solution consisting of HI, I 2 and H 2 O could be recycled as a reactant to the Bunsen reaction section from the HI decomposition section. In this study, characteristics of the Bunsen reaction using the HI x solution in a co-current flow mode were investigated experimentally. In particular, we studied the effects of the operating variables (feed rates of reactants, H 2 O and I 2 feed concentrations, temperature and volume of reaction zone) on the characteristics of the Bunsen reaction under steady-state conditions. Increasing the H 2 O feed concentration and decreasing the I 2 feed concentration improved the extent of the Bunsen reaction. When increasing the temperature, the purity of the Bunsen products improved, but the SO 2 conversion decreased. Characteristics of the Bunsen reaction were not affected by the variation in the volume of reaction zone. We concluded that SO 2 /HI/I 2 /H 2 O feed molar ratio controlled in the ranges of 1/1.8–2.0/3.9–4.1/14.8–15.6 was advantageous to achieve high SO 2 conversion and improve separation performance of the Bunsen products at 333 K.