Resumen
Acids solids sulfonated carbons Starbons-300 were prepared by using a mixture of ClSO 3H/H 2SO 4 and H 2SO 4 (98%) as sulfonating agents. Depending on the sulfonation method used important effects were found on the acidity, textural properties and activity. SO 3H groups linked to the Starbons-300 surface were observed by FTIR photoacustic spectroscopy. The functional groups were characterized by NMR 13C solids and liquids and HSQC liquid of Starbons-3002-H 2SO 4ClSO 3-TEPO. The acidity strength determined with zeta potential measurements and 31P MAS NMR showed strong acidity in the sulfonated samples. Total number of acid sites was determined by acid-base back titration. The content of SO 3H groups was estimated by measuring the cationic exchange capacity. The elemental analysis was carried out by XPS and SEM. The sulfonated Starbons-300 showed very high activity for the esterification of free fatty acids with ethanol. Conversions up to 60% of oleic acid and selectivity to the ester of 100% were reached after 3 h of reaction at 80°C. The results showed that the sulfonated carbon Starbons-300 catalysts are promising acids catalysts to be used in the esterification of free fatty acids with ethanol.
Idioma original | Inglés |
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Páginas (desde-hasta) | 128-138 |
Número de páginas | 11 |
Publicación | Fuel |
Volumen | 100 |
DOI | |
Estado | Publicada - oct. 2012 |