Oligomerization of a C-olefinic By-product Stream Using Cationic and Ziegler-Natta Catalysts

Abstract

Mixed hexene stream, a by- product of ethylene dimerization process, on oligomerization with Ziegler type and cationic catalyst systems predominantly yields dimers (C₁₂), trimers (C₁₈), and tetramers (C₂₄) Ziegler type catalysts based on Ti(IV) or Cr(III) and ethylaluminum sesquichloride as the co-catalyst mainly produce dimers (C₁₂) with selectivity greater than 78 per cent. The conversion to trimers(C₁₈) and tetramers (C₂₄) with cationic catalysts was better compared to Ziegler system. The use of anhydrous AlCl₃ or an alkylaluminum halide in comhination with <i>tert-</i>alkyl halide produces an active catalyst which readily converts the C₆ olefins to higher oligomers at ambient temperatures. The physical properties of the products have been measured to evaluate their suitability as synthetic lubricants.