| Journal: | Ciencia (Maracaibo) |
| Database: | PERIÓDICA |
| System number: | 000461331 |
| ISSN: | 1315-2076 |
| Authors: | Gómez Castillo, Dorisbeth1 Uzcátegui, Alvaro1 Imbert, Freddy Emilio1 Mercado, Jose |
| Institutions: | 1Universidad de Los Andes, Facultad de Ciencias, Mérida. Venezuela |
| Year: | 2010 |
| Season: | Oct-Dic |
| Volumen: | 18 |
| Number: | 4 |
| Pages: | 292-303 |
| Country: | Venezuela |
| Language: | Español |
| Document type: | Artículo |
| Approach: | Experimental |
| English abstract | The effect of alkaline treatment with LiOH, at two concentrations (0.05 and 0.20 M) and at two temperatures (24 and 78°C), on the acidity, textural properties and catalytic behaviour of a zeolite type MFI (Si/Al=10) was studied. The solids were characterized by X-ray diffraction, N 2 adsorption, energy dispersive x-ray and ammonium thermodesorption. The Si selective extrac - tion changed the chemical composition and led to an increase in the external surface and mesopore volume. The oppose effects of the diverse processes occurring during the alkaline treatment make that final acidity be a complex function of the treatment variables concentra - tion, temperature and time. Mesopore formation high temperature treatment led to higher spe - cific surface areas and pore volumes. The catalytic tests showed, that the catalytic activity, in the case of n-hexane cracking is controlled by catalyst acidity, while, in the case of m-xylene isomerization, the activity is rather controlled by the accessibility to the acid sites and the selec - tivity by the diffusional path. The treatment with LiOH was effective for increasing the access to the acid sites, reducing the channel blockage and the difusional path; thus, increasing catalyst activity and reducing the para-selectivity |
| Disciplines: | Química |
| Keyword: | Química inorgánica, Actividad catalítica, LiOH, Zeolitas, Zeolitas MFI |
| Keyword: | Inorganic chemistry, Catalytic activity, LiOH, MFI Zeolites, Zeolites |
| Full text: | https://produccioncientificaluz.org/index.php/ciencia/article/view/9990/9977 |
