Comparison of impregnation, liquid- and solid-state ion exchange procedures for the incorporation of nickel in HMFI, HMOR and HBEA

Nickel containing HMFI, HMOR and HBEA zeolites was prepared by impregnation and liquid- and solid-state ion exchange. The kinetics of the solid-state ion exchange of the protons (Bronsted acid sites) with NiCl₂ was followed by IR and TPE measurements. The results were compared to catalysts prepared by liquid-phase ion exchange and by incipient wetness impregnation. The level of ion exchange reached 100% when the solid-state procedure was used, whereas the exchange level was limited in the case of liquid exchange. The exchange degree increased in the sequence BEA < MFI < MOR. The differently prepared nickel containing zeolites showed a comparable activity and selectivity for the n-nonane hydroconversion with Ni/HMFI as the most active and Ni/HBEA as the most selective catalyst. (C) 2000 Elsevier Science B.V. All rights reserved.