USE OF AN ALUMINOSILICATE TYPE CATALYST CONTAINING GALLIUM IN FLAVORING LIGHT CUTS CONTAINING MOSTLY HYDROCARBONS WITH 2 CARBON ATOMS PER MOLECULE.

Abstract

L'invention concerne l'utilisation d'un catalyseur zéolithique en aromatisation d'une coupe de gaz légers C2 en présence d'oléfines. Le procédé d'aromatisation est effectué dans au moins un réacteur à lit circulant, en présence d'un catalyseur sous forme de billes, le catalyseur ayant généralement la composition suivante exprimée en poids: a) 0,01 à 10 % en poids de gallium b) 0,1 à 99,49 % d'une matrice c) 0,5 à 99,89 % d'une zéolithe de formule chimique approchée suivante: M2 / n O, Al2 O3 , xSiO2 où M représente un proton et / ou un cation métallique, n est la valence dudit cation, x est un nombre compris entre 12 et 1000, ladite zéolithe ayant une structure MFI et étant en outre synthétisée en milieu fluorure et possédant une teneur en fluor comprise entre 0,01 et 1,5 % en poids incorporée lors de la synthèse.

Description

This addition concerns the use of an aluminosilicate-type catalyst comprising an MFI-structured zeolite, synthesized in a fluoride medium, containing silicon, aluminum, and gallium, in the aromatization reactions of light fractions containing predominantly two carbon atoms per molecule in the presence of olefins and inert gases such as methane, nitrogen, carbon monoxide, and hydrogen. Aromatization is carried out in at least one circulating bed catalyst reactor. It is therefore appropriate for the catalyst to be used in bead form. This addition also relates to the use in aromatization of C2-rich (ethane and ethylene) cuts of an aluminosilicate-type catalyst with the following composition expressed by weight: a) 0.01 to 10% by weight of gallium, preferably 0.3 to 7%, b) 0.1 to 99.49% (and preferably 10 to 40%) of a selected matrix in the group formed by alumina, silica, magnesia, a clay and any combination of at least two of the aforementioned compounds and c) 0.50 to 99.89% (and preferably 60 to 90%) of a zeolite synthetic in fluoride medium of approximate chemical formula usually the following M2 / nO, A1203, xSi02, where M represents a proton and / or a metallic cation n is the valence of the cation x is a number between 12 and 1000 (mole ratio) SiO2 / A12O3), zeolite having a fluorine content between 0.01 and 1.5% by weight, preferably 0.1 to 1% by weight, fluorine being incorporated during the synthesis, the said zeolite is also characterized by an X-ray diffraction pattern shown in the Table 1 of the main patent. Using the techniques of the present addition, very stable aromatic selectivities were observed under long operating conditions of the order of 500 hours and more, depending on the operating conditions used.

Claims

DEMANDS 1) Use according to claim 1 of the main patent, for the flavoring of a cup made up mostly of hydrocarbons with 2 carbon atoms per molecule of a catalyst containing by weight a) 0.01 to 10% gallium, b) 0.1 to 99.49% of a matrix chosen from the group constituted by alumina, silica, magnesia, a clay and all a combination of at least two of the aforementioned compounds, c) 0.50 to 99.89% of a zeolite synthesized in a fluoride medium, with a SiO₂ / Al₂O molar ratio between 12 and 1000, said 2 23 zeolite also having a fluorine content between 0.01 and 1.5% by weight, the fluorine being incorporated during the synthesis of the said zeolite, which has a diagram of X diffraction conforming to Table 1 of the main patent. 2) Use according to claim 1 of a catalyst containing 10 to 40% matrix and 60 to 90% zeolite. 3) Use according to claim 1 of a catalyst in the form of marbles, the flavoring being carried out in at least one circulating bed catalyst reactor.