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MCM - 41 supported phosphotungstic acid for the hydroxyalkylation of phenol to phenolphthalein / Ajay Jha in Industrial & engineering chemistry research, Vol. 51 N° 10 (Mars 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 10 (Mars 2012) . - pp. 3916–3922 Titre : MCM - 41 supported phosphotungstic acid for the hydroxyalkylation of phenol to phenolphthalein Type de document : texte imprimé Auteurs : Ajay Jha, Auteur ; Ajit C. Garade, Auteur ; Subhash P. Mirajkar, Auteur Année de publication : 2012 Article en page(s) : pp. 3916–3922 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Phosphotungstic  acid  Hydroxyalkylation Résumé : A novel application of phosphotungstic acid, H3PW12O40 (PWA) supported on MCM-41 molecular sieve as a solid acid catalyst has been demonstrated for the synthesis of phenolphthalein by hydroxyalkylation of phenol and phthalic anhydride. PWA/MCM-41 (20%) showed the highest activity as compared to that of parent PWA and MCM-41 individually, due to the excellent dispersion of PWA on MCM-41 leading to the redistribution of Bronsted and Lewis acid sites on MCM-41. The effect of PWA loading on phthalic anhydride conversion and phenolphthalein selectivity was also studied. All these prepared catalysts were characterized by XRD, N2 adsorption–desorption isotherm, pyridine-FTIR, and NH3-TPD. The effect of various reaction parameters, namely, mole ratios, catalyst concentration, temperature, reaction time, and percentage of PWA present in the catalysts on conversion and selectivity of products has been also investigated. The utility of 20% PWA/MCM-41 catalyst was established by its efficient activity for hydroxyalkylation of phenol and p-cresol with formaldehyde to the corresponding dihydroxydiarylmethane products. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201989g [article] MCM - 41 supported phosphotungstic acid for the hydroxyalkylation of phenol to phenolphthalein [texte imprimé] / Ajay Jha, Auteur ; Ajit C. Garade, Auteur ; Subhash P. Mirajkar, Auteur . - 2012 . - pp. 3916–3922. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 10 (Mars 2012) . - pp. 3916–3922 Mots-clés : Phosphotungstic  acid  Hydroxyalkylation Résumé : A novel application of phosphotungstic acid, H3PW12O40 (PWA) supported on MCM-41 molecular sieve as a solid acid catalyst has been demonstrated for the synthesis of phenolphthalein by hydroxyalkylation of phenol and phthalic anhydride. PWA/MCM-41 (20%) showed the highest activity as compared to that of parent PWA and MCM-41 individually, due to the excellent dispersion of PWA on MCM-41 leading to the redistribution of Bronsted and Lewis acid sites on MCM-41. The effect of PWA loading on phthalic anhydride conversion and phenolphthalein selectivity was also studied. All these prepared catalysts were characterized by XRD, N2 adsorption–desorption isotherm, pyridine-FTIR, and NH3-TPD. The effect of various reaction parameters, namely, mole ratios, catalyst concentration, temperature, reaction time, and percentage of PWA present in the catalysts on conversion and selectivity of products has been also investigated. The utility of 20% PWA/MCM-41 catalyst was established by its efficient activity for hydroxyalkylation of phenol and p-cresol with formaldehyde to the corresponding dihydroxydiarylmethane products. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201989g