Patent ID: 7550643

Claim:
A method of operating a fixed-bed alkylation reactor having at least one catalytic flow channel comprising: a) obtaining a feed stream comprising isobutane admixed with an amount of an olefin lower than that required for significant polymerization; b) passing the feed stream into the catalytic flow channel wherein the catalytic flow channel defines a mass-transfer-limiting boundary layer limiting the rate of mass transfer of olefin to the catalyst surface to a value lower than that required for significant polymerization; c) contacting the feed stream with an alkylation catalyst positioned on the catalyst surface beneath the mass-transfer limiting boundary layer, thereby reacting isobutane with the olefin; and d) producing an alkylate product; wherein the catalytic flow channel defining a monolith having an upstream inner surface having no active alkylation catalyst and a downstream inner surface comprising an active alkylation catalyst positioned thereon.