Phase composition and formation of cobalt-copper cement catalysts

Abstract

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.