Alcohol Synthesis from CO , H , and Olefins over Alkali-Promoted Au Catalysts-A Catalytic and In situ FTIR Spectroscopic Study.

Au/TiO and Au/SiO catalysts containing 2 wt % Au and different amounts of K or Cs were tested for alcohol synthesis from CO , H , and C H /C H . 1-Propanol or 1-butanol/isobutanol were obtained in the presence of C H or C H . Higher yields of the corresponding alcohols were obtained over TiO -based catalysts in comparison with their SiO -based counterparts. This is caused by an enhanced ability of the TiO -based catalysts for CO activation, as concluded from in situ fourier-transform infrared (FTIR) spectroscopy and temporal analysis of products (TAP) studies. The synthesized carbonate and formate species adsorbed on the support do not hamper CO conversion into CO and the hydroformylation reaction. The transformation of Au to active Au sites proceeds during an activation procedure. As reflected by CO adsorption and scanning transmission electron microscopy, the accessible Au sites are influenced by the amount of alkali dopants and the support. FTIR data and TAP tests reveal a very weak interaction of C H with the catalyst, suggesting its quick reaction with CO and H after activation on Au sites to form propanol and propane.