DIFFUSE REFLECTANCE FOURIER-TRANSFORM IR STUDIES ON THE ROLE OF CATALYST SUPPORT ON SELECTIVITY IN ETHENE OXIDATION

Infrared spectroscopy (DRIFTS) was used to study the role of adsorption on the support material on the selectivity to ethylene oxide in ethylene oxidation. With silver catalysts supported on high surface area alumina, no selectivity to ethylene oxide was observed. DRIFTS studies also showed that significant ethylene adsorption on the alumina support was occurring. Further studies on the high surface area alumina support indicated that hydroxyl groups play a major role in ethylene adsorption on the support. With catalysts where there was no evidence of ethylene adsorption on the support, such as silver on low surface area alumina and silver on silica, ethylene oxide was formed.