CHARACTERIZATION AND ACTIVITY OF PT-SN AL2O3 CATALYSTS OF DIFFERENT PREPARATION - COIMPREGNATION AND NEW PT-SN PRECURSOR/

A new bimetallic Pt-Sn compound [Pt(NH3)(4)][SnCl6] has been used as p recursor for the preparation of supported Pt-Sn/A/O-2(3) catalysts. A comparison of a dried sample with that prepared by coimpregnation disp lays different behaviour in TPR, chemisorption. The initial catalytic activity properties were checked in the reactions of cyclohexane dehyd rogenation and cyclopentane ring opening, while n-hexane skeletal reac tions were used to probe the quasisteady-state activity. The catalyst prepared via the Pt-Sn complex precursors exhibited somewhat lower spe cific activity. This fact, together with enhanced olefin formation fro m n-hexane was taken as an indication of lower amount of contiguous Pt atoms and some electronic interaction between Pt and Sn in that catal yst.