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Bibliographic Information
Characterization of Co,Al-MCM-41 and its activity in the t-butylation of phenol using isobutanol. Karthik, M.; Tripathi, A. K.; Gupta, N. M.; Vinu, A.; Hartmann, M.; Palanichamy, M.; Murugesan, V. Department of Chemistry, Faculty of Science and Humanities, Anna University, Chennai, India. Applied Catalysis, A: General (2004), 268(1-2), 139-149. Publisher: Elsevier Science B.V., CODEN: ACAGE4 ISSN: 0926-860X. Journal written in English. CAN 141:158906 AN 2004:461160 CAPLUS
Abstract
Co,Al-MCM-41 catalysts with various nSi/(nCo + nAl) ratios were synthesized and extensively characterized by low-angle XRD, TGA/DTG, BET, AAS, DRIFT, UV-Vis DRS and ESR. UV-Vis DRS and ESR studies reveal that cobalt in Co,Al-MCM-41 is highly sym. and occurs in tetrahedral coordination. Some of the cobalt atoms are transformed into the cobalt oxide form when nSi/(nCo + nAl) is increased to 20. T-Butylation of phenol with isobutanol was studied in the vapor phase as a model reaction at temps. between 200 and 500癈. The products obtained were O-tert-Bu phenol (OTBP), 2-tert-Bu phenol (2TBP) and 4-tert Bu phenol (4TBP). O-Butenyl phenol (OBP) and 2-butenyl phenol (2BP) were also obsd. along with normal alkylated products. The phenol conversion drastically increased with temp. over all the catalysts. The activity of the catalysts followed the order of Co,Al-MCM-41 (20) > Co,Al-MCM-41 (50) > Co,Al-MCM-41 (80) > Al-MCM-41 (23). The influences of various parameters such as temp., reactant feed ratio and feed rate, time on stream on conversion and products selectivity were studied and the salient results are discussed. |
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