HIDROISOMERIZACION DE CORTES PARAFINICOS CONTENIENDO BENCENO SOBRE CATALIZADORES Pt/WO3-ZrO2.

VIVIANA M. BENITEZ, CAROLINA CORTI, JUAN C. YORI, JAVIER M. GRAU, CARLOS R. VERA*, CARLOS L. PIECK, JOSÉ M. PARERA

Santa Fe-Argentina

Congreso; XIV Congreso Argentino de Catálisis; 2005

INCAPE-INTEC

This contribution studies the feasibility of carrying out the elimination of benzene from paraffinic feedstocks sent to the naphtha isomerization unit with economy of equipment and sparing of pretreatment steps by hydrogenating benzene to cyclohexane (CH) and isomerizing partly the latter to methylcyclopentane (MCP) in the same isomerization unit, loaded with a Pt/WO3-ZrO2 catalyst.  The temperature of calcination of the catalysts affect in opposite ways the acid and metal functions.  The hydrogenating capacity of Pt mildly decreases at higher temperatures due to an increasing interaction with the support while the isomerization capacity is strongly enhanced due to the creation of strong acid sites.  The optimum catalysts is the one calcined at 800 °C.  The inhibition of the hydrogenolytic activity due to a support effect enables the suppression of ring-opening and prevents a drop in the octane number (blending RON) (RONMCP=107, RONCH=110) in case C6 acyclic isomers are produced with a majority of monomethylated species (RON»82-86). In the reaction conditions of this work the conversion of benzene is not complete (90%) due in part to a thermodynamic limitation for its transformation to cyclohexane and also because of the low conversion to methylcyclopentane.  Higher conversion would demand a higher reaction temperature or a higher residence time (higher [catalyst mass / benzene flowrate] ratio).