Sol-Gel Synthesis and Effects of Neodymium and Europium Oxides on the Structuring of Calcium Monoaluminate

Calcium monoaluminate was synthesized by the sol–gel method and the effect of europium and neodymium oxides on the synthesis and structuring kinetics was studied in the temperature range 500 – 1000°C. It was determined that the formation of the structure of calcium monoaluminate occurs at 1000°C and with exposure for 4 h of a xerogel obtained based on a mixture of Al(NO₃)₃ + Ca(NO₃)₂ at a compound ratio of 2 : 1, respectively. In the sample obtained, the intermediate mineral is mayenite Ca₁₂Al₁₄O₃₃. With the introduction of the mineralizing europium oxide Eu₂O₃ in an amount of 1.5 wt.% greater than 100 wt.% in Al(NO₃)₃ + Ca(NO₃)₂ composition, at a synthesis temperature of 1000°C, the exposure time for maximum formation of calcium monoaluminate is reduced to 1 h. In samples containing Nd₂O₃, for the maximum formation of calcium monoaluminate at the same exposure time, it is necessary to introduce it in an amount of 5 wt.%.