Oligomerization of ethene in a slurry reactor using a nickel(ll)-exchangedsilica-alumina catalyst

Ethene oligomerization kinetics on a nickel(II)-exchanged silica-alumina ca talyst were determined using a mechanically stirred laboratory-scale slurry reactor. With analysis of both gaseous and liquid outlets from the reactor , the various reaction rates could be correlated in terms of liquid-phase r eactant concentrations. In addition, vapour-liquid equilibria could be meas ured. All experiments were carried out at an operating pressure of 3.5 MPa and the temperature was varied between 120 and 180 degreesC, The feed MHSV was varied between 1 and 12, Three second-order reactions were used to corr elate the observed rate of ethene conversion and the Schulz-Flory-type prod uct distribution: ethene-ethene dimerization, ethene-oligomer reaction, and butene-butene dimerization. The inferred rate of butene dimerization was c onfirmed experimentally using butene as the reactant feed, Very little deac tivation was observed during experimental runs lasting 900 h or more, with conversions being maintained throughout at over 908. Oligomers up to C-16 w ere obtained, The absolute rate of ethene oligomerization typically exceede d 11.5 g g(cat)(-1), h(-1). It was shown experimentally that both gas-liqui d and interparticle mass transfer limitations were absent in this work. (C) 2000 Academic Press.