Abstract: This invention relates to a two-stage conversion of olefins into aromatic hydrocarbon mixtures by contacting them in the first stage with a crystalline metal silicate and in the second stage with a crystalline gallium silicate.

Abstract: A process is disclosed for converting C.sub.2 -C.sub.4 paraffins into aromatic gasoline over a crystalline gallium silicate having a SiO.sub.2 /Ga.sub.2 O.sub.3 molar ratio between 25 and 250, which silicate has been subjected once or several times to a two-stage treatment comprising reduction at a temperature of 400.degree.-650.degree. C. and oxidation at a temperature of 350.degree.-700.degree. C. Optionally the gallium silicate is subjected to precalcining at a temperature of 600.degree.-1000.degree. C., the number of times of the two-stage treatment being determined by the fact whether or not said gallium silicates have been subjected to such precalcination.

Abstract: A process for converting C.sub.2 -C.sub.5 olefins into middle distillates at a temperature of 150.degree.-300.degree. C. over a catalyst which has been prepared by depositing at least 0.1% w Ni or Co by ion exchange onto a crystalline metal silicate having a ZSM-5 structure.

Abstract: A process is disclosed whereby a full range catalytically cracked gasoline is upgraded over a mixture of Zn/Cr catalyst and a crystalline iron silicate catalyst having a SiO.sub.2 /Fe.sub.2 O.sub.3 molar ratio of 10-250 or a mixture of a Zn/Cr catalyst and a crystalline iron/aluminum silicate catalyst having a SiO.sub.2 /Fe.sub.2 O.sub.3 molar ratio below 250 and a SiO.sub.2 /Al.sub.2 O.sub.3 molar ratio of at least 500.