Replacing TK-437, the new generation TK-447 SiliconTrap™ is a very high surface area catalyst for silicon pick-up and desulfurization of coker naphtha feedstock. This catalyst has a low hydrodesulfurization (HDS) activity and should be used in combination with TK-441 SiliconTrap™ as a guard catalyst. TK-447 SiliconTrap™ has the same high surface area per volume as TK-441 SiliconTrap™, but due to a lower metals loading, the silicon pick-up capacity is even higher than that of TK-441 SiliconTrap™ on a volume basis. TK-447 SiliconTrap™ is also the recommended catalyst for diolefin saturation. Diolefin hydrotreating is best carried out in a separate guard reactor operating at low operating temperature (180–220°C).