| 摘要 |
Hydrocarbon conversion reactions, e.g. hydrocracking, reforming, alkylation of isoparaffins and aromatics with C2- 15 olefins, dealkylation of alkyl substituted aromatics, e.g. toluene, isomerization of paraffins to isoparaffins, polymerization of C2 to C8 olefins to products boiling in the gasoline range are carried out using a catalyst prepared by ion-exchanging a crystalline zeolitic molecular sieve having SiO2:Al2O3 at least 1.8 with non-metal cations, ion-exchanging the non-metal cations with to a temperature of at least 350 DEG C. but below a temperature at which the crystalline structure of the sieve would be destroyed. A Pd-loaded Mg-exchanged sieve is used to hydrocrack a feed containing 27 volume per cent aromatics, 72 volume per cent saturates, with a hydrogen to feed ratio 8,500 scf/bbl., reaction pressure 1000 p.s.i.g. General hydrocracking conditions mentioned are temperature 150-475 DEG C., pressure 300-8000 p.s.i.g., WHSV 0.5-5.5, hydrogen to hydrocarbon mole ratio 5-40. Ca-, Zn- and Mn-exchanged sieves are used in the reaction of benzene and propylene. General alkylation conditions mentioned are temperature 20-300 DEG C., pressure atmospheric to 1000 p.s.i.g., typical feeds being iso C4-C6 paraffins plus gaseous C4-C6 olefins or aromatic hydrocarbons plus C2-C15 olefins. A Pt-loaded sieve may be used in hydrocarbon isomerization, typical conditions being temperature 250-425 DEG C., WHSV 1-10, hydrogen to hydrocarbon ratio 0.3 to 1, pressure between 100 and 1000 p.s.i.g. A noble metal-loaded catalyst is used for reforming, general conditions being temperature 300-600 DEG C., pressure 300-600 p.s.i.g., hydrogen to hydrocarbon mole ratio 1:1 to 20:1, WHSV 0.1 to 7. The non-metal loaded catalyst is used for polymerization of C2-C8 olefins, preferred conditions being temperature 0-300 DEG C., pressure atmospheric-10,000 p.s.i.g., WHSV 0.01-10.ALSO:A catalyst is prepared by a process comprising ion-exchanging a crystalline zeolitic molecular sieve having a silica to alumina mole ratio of at least 1.8 with non-metal cations, ion-exchanging the non-metal cations with polyvalent cations and heating the zeolite to a temperature of at least 350 DEG C. but below a temperature at which the crystalline structure of the zeolite would be destroyed. The zeolite may be zeolite g (exemplified), zeolite A, D, R, S, T, X, L, "zeolon", analcite, chabazite or erionite. The non-metal cation may be ammonium (exemplified), hydrogen, or quaternary ammonium, for example methyl quaternary ammonium. The polyvalent metal may be Be, Mg (exemplified) Ca, Sr, Ba, R.E. including Ce, Cr, Mn, Zn. A catalytically active metal may be introduced in quantity at least 0.05 wt. per cent. The metal may be Pd, (exemplified), Cu, Ag, Au, Zn, Cd, Ti, Sn, Pb, V, Sb, Bi, Cr, Mo, W, Mn, Re, Fa, Co, Ni, Pt. The catalyst may be pelleted.ALSO:A catalyst is prepared by a process comprising ion-exchanging a crystalline zeolitic molecular sieve having a silica to alumina mole ratio of at least 1.8 with non-metal cations, ion-exchanging the non-metal cations with polyvalent cations and heating the zeolite to a temperature of at least 350 DEG C but below a temperature at which the crystalline structure of the zeolite would be destroyed. The zeolite may be zeolite Y (exemplified), zeolite A, D, R, S, T, X, L, "zeolon", analcite, chabazite or erionite. The non-metal cation may be ammonium (exemplified), hydrogen, or quaternary ammonium, for example methyl quaternary ammonium. The polyvalent metal may be Be, Mg (exemplified) Ca, Sr, Ba, R, E, including Ce, Cr, Mn, Zn. A catalytically active metal may be introduced in quantity at least 0.05 wt.%. The metal may be Pd, (exemplified), Cu, Ag, Au, Zn, Cd, Ti, Sn, Pb, V, Sb, Bi, Cr, Mo, W, Mn, Re, Fe, Co, Ni, Pt. The catalyst may be pelleted, optionally with clays, alumina, silica, starches, sugars or graphite as additives. A catalyst test reactor comprises a 4/sv x 1" stainless steel tube having an axial thermocouple well and surrounded by 6" thick alumina blocks. The 16" long catalyst bed is diluted with quartz chips and is supported in the centre of the reactor by a post-heat section of 1/8 " stainless steel balls, the pre-heat section which fills the rest of the reactor also being of 1/8 " stainless steel balls. |
