 ExSact catalyzes the alkylation of light olefins with isobutane. As shown in
the diagram, there are multiple steps that are involved in the alkylation reaction.
Maximizing the rate of hydride transfer while minimizing the rate of olefin polymerization,
coke formation, and cracking, is the key to obtaining high octane alkylate.
Coke formation is a central issue in isoparaffin alkylation.
In liquid acid systems, coke occurs as “acid-soluble
oils” which must be removed from the reactor and treated
to recover the acid. In most solid acid catalysts, coke molecules
tend to clog the fine pore structure of the catalysts, leading
to rapid deactivation.
Exelus has developed a revolutionary solid acid catalyst
that is able to achieve a quantum leap in performance over
conventional solid-acid catalysts. The catalyst is engineered
to overcome traditional solid-acid catalyst performance problems,
resisting deactivation by coke while maintaining high selectivity
and yield. This level of performance is achieved by optimizing
the active site strength, location, and density as well as
the catalyst pore structure on multiple levels.
The robust ExSact solid-acid catalyst produces alkylate
with a superior octane rating over a wide range of operating
temperatures (50-100°C), olefin space velocities (0.1
to 1.0 1/hr) and feed composition (I/O ratios from 10 to
15). The catalyst does not require extensive feedstock pretreatment
and is easily regenerated in the reactor.
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