Abstract: The influence of carbon monoxide (CO) in the gas phase and silicon (Si) in the liquid phase on diesel deep hydrodesulfurization was studied. The results show that CO inhibits the HDS performance of catalyst and with the increase of CO concentration; the inhibition increases and then gradually becomes mild. However, the inhibition of CO is reversible. The Si in liquid phase poisons the catalyst and shortens the catalyst lifetime. It is found that when the SiO2 deposition reaches 3.31%, the activity loss of catalyst is more than 10 ℃.

Key words: diesel, HDS, carbon monoxide, silicon