KEGGIN HETEROPOLY ACIDS AS AN EFFICIENT CATALYSTS FOR PHOTOCATALYTIC OXIDATION OF AROMATIC ALDEHYDES

Yehia, F.Z. Z.; Ragab, H.; Elkady, G. M.; Khalil, M.; Mady, A. H.; Yousry, A.; Elnaggar, E. M.; El Afandy, A.; Hussein, A. M.

doi:10.21608/absb.2017.8112

KEGGIN HETEROPOLY ACIDS AS AN EFFICIENT CATALYSTS FOR PHOTOCATALYTIC OXIDATION OF AROMATIC ALDEHYDES

Document Type : Original Article

Authors

¹ Department of Petrochemicals, Egyptian Petroleum Research Institute (EPRI ), Nasr City, Cairo, Egypt

² Faculty of Science, Demietta University, Demietta, Egypt.

³ Department of Chemistry, Alazhar University, Nasr City, Cairo, Egypt.

⁴ Nuclear Materials Authority, Cairo, Egypt.

10.21608/absb.2017.8112

Abstract

Photocatalytic oxidation of aromatic aldehydes to related carboxylic acids was investigated in the presence of some Keggin heteroploy acids as phosphomolybdic acid H₃PMo₁₂O₄₀ (PMo), silicotungestic acid H₄SiW₁₂O₄₀ (SiW) and phosphotungstic acid H₃PW₁₂O₄₀ (PW). Keggin acids can catalyze the oxidation of 4-carboxybenzaldehyde (4-CBA) and p-tolualdehyde (p-Tol) under homogeneous reaction. Also, for additional studies, we reconnoitered the application of Keggin catalyst in the presence of persulfate (PS) as oxidizing agent. Our results showed that in the presence of PS and (6 watt)UV light, the most active catalyst among the used Keggin acids is the phosphomolybdic acid (80.9% yield) due to the high oxidative ability of molybdenum . The effects of catalyst concentration, time and oxidant load have been studied. The mechanistic aspects of the reaction also have been discussed.

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