关键词: 催化裂化, 镍, 污染, 活性, 选择性

Abstract: The effect of nickel contamination including nickel contents and contamination ways, on the activity and selectivity of catalytic cracking catalysts was investigated. Results showed that the ways of nickel deposited on the catalyst played an important role on the catalytic performance, and the cracking activity of catalyst decreased with the increase of nickel content. Due to the strong catalytic dehydrogenation of nickel, negative effect on reaction selectivity was observed, such as the yields of dry gas and coke increased. However, the effect of deposited nickel on selectivity was varied with the ways of nickel deposition, e.g. nickel of industrial equilibrium catalyst had less negative effect than that of lab contaminated catalyst. It was found that the nickel of industrial equilibrium catalyst reduced the catalyst activity by way of decrease the number of Brönsted acid sites, and the nickel of lab contaminated catalyst affected the catalyst activity and selectivity by way of decrease the active site accessibility due to the blocking of catalyst channels and zeolite pores.

Key words: catalytic cracking, nickel, contamination, activity, selectivity