US Patent 7759533 Lightly branched higher olefin oligomerization with surface modified zeolite catalyst

A substantially surface-deactivated catalyst composition that is stable at least to 300° C. The catalyst includes a zeolite catalyst (e.g., ZSM-22, ZSM-23, or ZSM-57) having active internal Brönsted acid sites and a surface-deactivating amount of a rare earth or yttrium oxide (e.g., chosen from lanthanum oxide or lanthanides oxide). This catalyst is preferably used in a process for producing a higher olefin by oligomerizing a light olefin, wherein the process includes contacting a light olefin under oligomerization conditions with the substantially surface-deactivated catalyst composition.