Studies of styrene oxidation by catalyst based on zeolite-Y nanohybrid materials

• Published in: Journal of molecular catalysis. A, Chemical Chemical, 2016-12, Vol.424, p.203-219
• Main Authors: Desai, Nisheeth C., Chudasama, Jiten A., Karkar, Tushar J., Patel, Bonny Y., Jadeja, Krunalsinh A., Godhani, Dinesh R., Mehta, Jignasu P.
• Format: Article
• Language: English
• Subjects: Nanohybrid materials; Styrene oxidation; Zeolite-Y
• ISSN: 1381-1169; 1873-314X
• DOI: 10.1016/j.molcata.2016.08.031

[Display omitted] •We have combined VO(IV) based neat and their entrapped complexes into the nanopores of zeolite-Y.•The comparative studies of spectroscopic, thermal, morphological and crystalline properties of complexes were achieved.•The catalytic activities were tried over oxidation of styrene reaction using TBHP as an oxidizing agent.•The reaction parameters were optimized for higher oxidation with higher selectivity towards allylic products.•Among all catalysts, [VO(HNIMMPP)(H2O)]-Y catalyst showed higher catalytic (TOF, 114.75h−1) activity with 45% selectivity of benzaldehyde. Metal complexes of VO(IV), Mn(II), Fe(II), Co(II), Ni(II), Cu(II) and HNIMMPP (4-(((2-hydroxy-5-nitrophenyl)imino)methyl)-3-methyl-1-phenyl-1H-pyrazol-5-ol) schiff base ligand have been synthesized within zeolite-Y along with neat one. Synthesized compounds were characterized by physico-chemical techniques such as elemental analysis of catalysts, BET, XRD, SEM, FT-IR, UV–vis, ICP-OES and TGA. Synthesized zeolite-Y based nanohybrid materials and their uncovered complexes were used in styrene oxidation with TBHP as an oxidizing agent. Oxidation reaction of styrene furnished benzaldehyde as the major product and styrene glycol, chalcone and 2-phenyloxirane as minor products. Amongst all catalysts, [VO(HNIMMPP)(H2O)]-Y produced the highest conversion at 93.35% and selectivity of benzaldehyde (45.70%) was the greatest. These nanohybrid materials can be easily reprocessed and recovered within these reaction parameters. The reaction mechanism for catalytically oxidized styrene is discussed in the present paper.