The variation of surface morphology for the series of CaOeLa2O3
catalysts with different Ca/La atomic ratio was determined by SEM
analysis. The SEM micrographs showed the agglomerated particles
of cubic CaO structure and La2O3 with irregular shape structure
(Fig. 4A and B). In low Ca content such as CL0.5 (Fig. 4C), the
spherical structure was observed due to mainly formation of La2O3
phase with symmetrical particle size distribution. With the
increased of Ca/La loading from 4.0 to 8.0 atomic ratio, the particle
agglomeration occurred with the formation of merging structure of
CaO with La2O3. It was presence of non-uniform structures
(spherical or cubic) with different size of particles (Fig. .4D and E).