Preparation of Copper Chromite by Vaccum Freezing Drying Method and Its Catalytic Activity for Sulfuric Acid Decomposition

Iodine sulfur (IS) process is one of the most promising routes for massive and CO 2 ‐free hydrogen production. Among the three reactions IS process composed, decomposition of sulfuric acid is the most energy intensive step and has to be conducted in the presence of catalyst. In this work, copper chromite (CuCr 2 O 4 ) was prepared, characterized, and used as the catalyst for sulfuric acid decomposition reaction. The co‐precipitation preparation method of CuCr 2 O 4 which featured in vacuum freezing drying (VFD), was applied, and the main factors which influence the structure of CuCr 2 O 4 such as pH values of the co‐precipitation solution and calcination temperature were investigated. Results showed that pH value affected the size of copper chromite granule, when pH was between 7 and 8, the size of prepared CuCr 2 O 4 was in nanometer scale. Calcination temperature influenced the purity of the crystal. The samples were characterized by XRD, TEM and BET. The catalytic activity of CuCr 2 O 4 prepared by VFD was evaluated and compared with CuCr 2 O 4 prepared by usual co‐precipitation method and Pt/Al 2 O 3 . Results showed that the activity of CuCr 2 O 4 was close to that of Pt catalyst, but apparently higher than that of CuCr 2 O 4 prepared by usual method. In addition, it presents good stability in the 70 h test. Therefore, it was promising to be used in the sulfuric acid decomposition step of IS process.