Phase composition and formation of cobalt-copper cement catalysts

Using x-ray phase analysis, DTA, DTG, and temperature-programmed reduction, we have studied the phase composition and formation of cobalt-copper cement catalysts obtained by chemical mixing of hydroxocarbonates of cobalt (CoHC) and copper (CuHC) with the aluminocalcium cement talyum, consisting of CaAl₂O₄ and CaAl₄O₇, in an aqueous ammonia medium. We have shown that when the components are mixed, exchange reactions occur with development of new phases of cobalt and copper hydroxoaluminates, calcite, gibbsite, Cu(OH)₂, CuO. We found that CaAl₂O₄ is more reactive than CaAl₄O₇. We have obtained data on the change in the phase composition upon thermolysis and reduction in H₂.N. D. Zelinskii Institute of Organic Chemistry, Academy of Sciences, 117913 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 1, pp. 48–54, January, 1992.