摘要 |
Process for the preparation of ferrierite which comprises maintaining an aqueous starting mixture containing at least one silicon compound, at least one aluminium compound, at least one alkali metal (M) compound and at least one organic nitrogen compound (RN) selected from the group consisting of piperidine, pyridine, allyl-substituted piperidines and -pyridines, piperazine, 4-picoline and 4-picoline-N-oxide, at an elevated temperature until crystalline ferrierite has formed, in which starting mixture the various compounds are present in the following molar ratios, the aluminium-, silicon- and alkali metal-compounds being calculated on basis of the oxides: SiO2 : M2O = 7.3 to 15.6, SiO2 : Al2O3 = 15.6 to 35.7, H2O : SiO2 = 5 to 500, and RN : SiO2 = 0.05 to 1.0. The ferrierite catalyst precursor thus prepared can after conversion into the hydrogen form be used as catalyst (carrier) for dewaxing hydrocarbon oils (e.g. lubricating base oils). |