Activity and selectivity of Group VIII, alkali-promoted Mn-Ni, and Mo-based catalysts for C2+ oxygenate synthesis from the CO hydrogenation and CO/H2/C2H4 reactions

Activity and selectivity of Group VIII metal catalysts, H2S-treated Group VIII metal catalysts, alkali-promoted Mn-Ni catalysts, and Mo-based catalysts toward higher oxygenates via the CO hydrogenation and ethylene hydroformylation (CO/H-2/C2H4) reactions at 545 K and 1 MPa have been studied, The catalysts exhibited a wide range of activity and selectivity for C-2 oxygenate synthesis. The selectivity toward C-2 oxygenates is attributed to the CO insertion capability of the catalyst. All of the catalysts tested, except H2S-treated Os, exhibited CO insertion activity in the CO/H-2/C2H4 reaction leading to C-3 oxygenate formation. Rh and Ru exhibited exceptionally high activity and selectivity for C-2 oxygenates in the CO/H-2 reaction and C-3 oxygenates in the CO/H-2/C2H4 reaction. Sulfur treatment of the catalysts poisoned CO dissociation and hydrogenation capability to various degrees for the Group VIII catalysts. Coprecipitated alkali-Mn-Ni catalysts showed low hydrogenation activity and good oxygenate selectivity. Mo-based catalysts showed the poorest activity and selectivity toward higher oxygenates at 1 MPa. Optimization of C-2 oxygenate activity and selectivity requires a proper balance between CO dissociation activity, CO insertion activity, and hydrogenation activity. (C)2000 Elsevier Science B.V. All rights reserved.