Active sites of Fluid catalytic cracking (FCC) catalyst are poisoned during operation in the FCC reactor due to causes including feedstock contaminant metals deposition. This leads to activity, selectivity and increas...Active sites of Fluid catalytic cracking (FCC) catalyst are poisoned during operation in the FCC reactor due to causes including feedstock contaminant metals deposition. This leads to activity, selectivity and increasing coking problems, thereby raising concern to the refiner. This work investigated effect of nickel coexisting with vanadium in the FCC feedstock on the standard FCC catalyst during cracking process, in which destruction of active sites occurs as a result of the metals deposition. Laboratory simulated equilibrium catalysts (E-cats) were studied by XRD, FTIR spectroscopy, N-2 adsorption, solid state MAS-NMR, SEM and H-2-TPR. Results revealed that vanadium, above a certain concentration in the catalyst, under hydrothermal conditions, is highly detrimental to the catalyst's structure and activity. Conversely, nickel hardly affects the catalyst structure, but its co-presence in the catalyst reduces destructive effects of vanadium. The mechanism of nickel inhibition of vanadium poisoning of the catalyst is discussed. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.展开更多
基金financially supported by the Joint Funds of the National Natural Science Foundation of ChinaChina National Petroleum Corporation(U1362202)+4 种基金National Natural Science Foundation of China(21206195)the Fundamental Research Funds for the Central Universities(14CX02050A,14CX02123A)Shandong Provincial Natural Science Foundation(ZR2012BM014)the project sponsored by Scientific Research Foundation for Returned Overseas Chinese Scholarthe support from Chinese Government under the Chinese scholarship scheme for international students
文摘Active sites of Fluid catalytic cracking (FCC) catalyst are poisoned during operation in the FCC reactor due to causes including feedstock contaminant metals deposition. This leads to activity, selectivity and increasing coking problems, thereby raising concern to the refiner. This work investigated effect of nickel coexisting with vanadium in the FCC feedstock on the standard FCC catalyst during cracking process, in which destruction of active sites occurs as a result of the metals deposition. Laboratory simulated equilibrium catalysts (E-cats) were studied by XRD, FTIR spectroscopy, N-2 adsorption, solid state MAS-NMR, SEM and H-2-TPR. Results revealed that vanadium, above a certain concentration in the catalyst, under hydrothermal conditions, is highly detrimental to the catalyst's structure and activity. Conversely, nickel hardly affects the catalyst structure, but its co-presence in the catalyst reduces destructive effects of vanadium. The mechanism of nickel inhibition of vanadium poisoning of the catalyst is discussed. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.