| 摘要 |
C2-C4 paraffins or hydrocarbon mixtures comprising more than 50 %w of C2-C4 paraffins are converted into an aromatic hydrocarbon mixture over a catalyst comprising gallium on a carrier and a crystalline metal silicate having a SiO2/(Y2O3 + Ga2O3) molar ratio of 10-500 (Y = Al, Fe, Co and/or Cr) and a Ga2O3/Y2O3 molar ratio lower than 1, and having an X-ray powder diffraction pattern after one hour's calcination in air in which pattern the strongest lines are shown at interplanar spacings d( ANGSTROM ) of 11.2 +/- 0.2; 10.0, +/- 0.2; 3.84 +/- 0.07; 3.72 +/- 0.06. The catalyst has been subjected at least once to a two-step treatment comprising a coke-deposition and a coke-burn off with an oxygen-containing gas at 350-700 DEG C. The quantity of gallium amounts to 1-10 %w, calculated on the quantity of crystalline metal silicate. The gallium-containing carrier is preferably an amorphous carrier or the crystalline metal silicate. |
