ISOBUTANE 2-BUTENE ALKYLATION OVER FAUJASITE-TYPE ZEOLITES IN A SLURRY REACTOR - EFFECT OF OPERATING-CONDITIONS AND CATALYST REGENERATION/

The isobutane/2-butene alkylation has been catalysed by acidic cubic f aujasites (H-FAU and CeY-98) and a hexagonal faujasite (H-EMT) in a se mibatch slurry reactor. H-EMT exhibited the best results during the re action with respect to an improved deactivation profile and moderate l oss of alkylate selectivity compared to both CeY-98 and H-FAU. Additio nally, H-EMT proved to be regenerable. The different catalytic behavio ur between H-EMT and H-FAU has been discussed in terms of differences in their crystal structure. Furthermore, we have focused on the influe nce of isobutane:2-butene molar ratio and temperature (simultaneously varied) on the catalytic behaviour at constant butene WHSV fed to the slurry reactor at optimum stirring conditions, CeY-98 was used as a mo del catalyst and the results were heated statistically by principal co mponent and partial least square analyses, The dependence of alkylate selectivity as well as yield related to temperature (T) and isobutane: 2-butene molar ratio (M) were found to be: Selectivity = 0.53 + 0.017 [M - 12.5] + 0.0003 [T - 90] + 0.0004 [T - 90] [M - 12.5]; Yield - 0.5 5 + 0.016 [M - 12.5] + 0.001 [T - 90] + 0.0004 [T - 90] [M - 12.5], wi thin the employed parameters (T is an element of 80-100 degrees C, M i s an element of 5-20). Both equations showed optima at low butene conc entrations, while the temperature was of minor importance. A high stir ring speed was essential to achieve optimal reaction conditions enlarg ing the alkylate yield and selectivity.