Copper addition to palladium increases both activity and selectivity in the selective hydrogenation of 1,3-butadiene to n-butenes. The bimetal catalyst (Cu/Pd:2/1(atomic)) hydrogenates the diene to virtually 100% conversion without significant n-butene isomerization or butane formation. While at moderate conversions monometallic palladium is quite selective for n-butene production, 1-butene is quickly isomerized and saturated at higher conversions resulting from butadiene's inability to monopolize the active surface at lower partial pressures. Copper also promotes higher trans-2-butene selectivity and modifies the rate dependence on 1,3-butadiene from zero to negative order. These results suggest a donor "ligand" effect in which copper changes the palladium's electronic character. The apparent activation energy for 1,3-butadiene hydrogenation over palladium is 14.9 $\pm$ 0.2 kcal/mol.
| Identifer | oai:union.ndltd.org:RICE/oai:scholarship.rice.edu:1911/13832 |
| Date | January 1994 |
| Creators | Furlong, Brian Keith |
| Contributors | Hightower, Joe W. |
| Source Sets | Rice University |
| Language | English |
| Detected Language | English |
| Type | Thesis, Text |
| Format | 149 p., application/pdf |
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