COMPARATIVE STUDY OF LA0.7CA0.3MN0.95FE0.05O3 PEROVSKITES PREPARED BY DIFFERENT METHODS AND EFFECT OF PREPARATION ON CATALYTIC ACTIVITY FOR HYDROXYLATION OF BENZENE

Document Type : Original Article

Author

Department of Chemistry, Faculty of Science, Al-Azhar University, Cairo, Egypt.

Abstract

Magnetic nanoparticles of La0.7Ca0.3Mn0.95Fe0.05O3 perovskites were synthesized by various wet chemical routes, namely co-precipitation, oxalate-gel and citrate-gel methods. Phase formation and crystal structure of the synthesized powders were examined by the X-ray diffraction (XRD) using the Rietveld analysis. The micro- structure was determined by means of scanning electron microscopy (SEM). Infrared transmission spectroscopy revealed that stretching and bending modes are influenced by preparation methods. Synthesis using the oxalate-gel method yielded incomplete reaction irrespective of the calcination temperature adopted. The citrate-gel method yielded better powder properties in terms of particle size and morphology as compared to co-precipitation synthesis. The highest activity for the catalytic oxidation of benzene to phenol in presence of H2O2 was obtained with the sample prepared by the citrate–gel method.

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