Abstract
The decomposition of acetic anhydride in liquid phase on a fosfotungstic Wells–Dawson heteropoly acid (HPA) was investigated by in situ ATR-FTIR spectroscopy. Transient and concentration-modulation excitation spectroscopy (MES) experiments in combination with phase-sensitive detection (PSD) were used to monitor the solid–liquid interface. The MES method is based on the periodic variation of a parameter of the reaction media such as, the reactant concentration. That periodic alteration causes varying infrared signals of the surface adsorbed species that are subsequently demodulated with the PSD methodology. Thus, the separation of the static signals from the changing ones is achieved, and species with different response can be observed in the spectra. Using MES-PSD coupled with ATR-FTIR, acetic anhydride was observed to decompose to acetic acid, acetate and acyl [CH3C(O)+] species, involving Brønsted acid sites of the HPA catalyst. The CH3C(O)+ is a very unstable intermediate species and it is the key intermediate in the Friedel–Crafts acylation reactions. Moreover, the acetate groups are spectator species since remain strongly adsorbed on the catalyst surface and do not further react.
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References
Burgüi T, Baiker A (2006) Adv Catal 50:227
Baurecht D, Fringeli UP (2001) Rev Sci Instrum 72:3782
Kresnawahjuesa O, Gorte RJ, White D (2004) J Mol Catal A Chem 208:175
Bachiller-Baeza B, Anderson J (2004) J Catal 228:225
Parida KM, Mallick S, Pradhan GC (2009) J Mol Catal A Chem 297:93
Sartori G, Maggi R (2006) Chem Rev 106:1077
Matkovic SR (2009) Ibuprofen synthesis: investigation of the applicability of fosfotungstic Wells Dawson heteropolyacid in the eco-friendly acylation of isobutylbenzene. Thesis, Universidad Nacional La Plata, Argentina
Ashima H, Chun W-J, Asakura K (2007) Surf Sci 601:1822
Kinoshita K, Suzuki S, Chun W-J, Takakusagi S, Asakura K (2009) Surf Sci 603:552
Matkovic SR, Valle GM, Gambaro LA, Briand LE (2008) Catal Today 133–135:192
Baurecht D, Porth I, Fringeli UP (2002) Vibr Spectrosc 30:85
Urakawaa A, Bürgi T, Baiker A (2008) Chem Eng Sci 63:4902
Okuhara T, Mizuno N, Misono M (1996) Adv Catal 41:113
Kozhevnikov IV (1998) Chem Rev 98:171
Sambeth JE, Baronetti GT, Thomas HJ (2003) J Mol Catal A Chem 19:135
Bellamy LJ (1975) The infrared spectra of complex molecules, 3rd edn. Chapman and Hall, London
Rachmady W, Vannice MA (2002) J Catal 207:317
Jackson SD, Kelly GJ, Lennon D (2000) React Kinet Catal Lett 70:207
Nakamoto K (1986) Infrared and Raman spectra of inorganic and coordination compounds, 4th edn. Wiley, New York
Collins SE, Matkovic SR, Bonivardi AL, Briand LE (2011) J Phys Chem C 115:700
Lee KY, Mizuno N, Okuhara T, Misono M (1989) Bull Chem Soc Jpn 62:1731
Acknowledgments
The authors acknowledge the financial support of the Agencia Nacional de Promoción Científica y Tecnológica (projects PICT Red 729/06 and PME 311/06), Universidad Nacional del Litoral (CAI+D 379-J/09) and Universidad Nacional de La Plata (Project 11 X-485).
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Aguirre, A., Bonivardi, A.L., Matkovic, S.R. et al. ATR-FTIR Study of the Decomposition of Acetic Anhydride on Fosfotungstic Wells–Dawson Heteropoly Acid Using Concentration-Modulation Excitation Spectroscopy. Top Catal 54, 229–235 (2011). https://doi.org/10.1007/s11244-011-9625-x
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DOI: https://doi.org/10.1007/s11244-011-9625-x