Abstract: An analysis study was conducted on the deactivated catalyst of a 2 million tons/year fixed bed residue hydrotreating unit after long-term operation in SINOPEC Jinling Petrochemical Co.,Ltd. The variation of metal deposition along the flow direction on the catalysts, radial distribution of deposited metal on the catalyst cross-section, relationship between sulfur content and metal deposition, and the carbon deposition on different catalysts were investigated. The deposition of Fe and Ca showed a clear decreasing trend along the flow direction, while the deposition of Ni and V first increased and then decreased along the flow direction. The deposition distribution of different metals on the catalysts was mainly related to the form of metal existence in the residue and the performance of series catalysts. Fe and Ca were concentrated on the outer surface of the catalyst, while Ni had a relatively uniform radial distribution in the cross-section. The radial distribution uniformity of V in the catalyst cross-section gradually decreased along the flow direction, mainly related to the pore structure properties of different types of catalysts. The amount of carbon deposition on the catalyst along the flow direction first decreased and then increased, which is related to the dynamic changes of the residue properties and the operating temperature of unit during the reaction process. Based on the above analysis study, follow-up improvement suggestions had been proposed.

Key words: fixed bed residue hydrotreating, deactivated catalyst, metal deposition, radial distribution, carbon deposit