Ir(CO)₂(acac)를 산성담체(γ-Al₂O₃, NaY)와 염기성담체(MgO, 염기성 제올라이트)에 담지시켜 Ir 촉매들을 제조하였다. 촉매들로 1-20 atm, 200-325℃, 0.5-3.0의 H₂/CO비의 조건에서 CO 수소화반응을 수행하였다. 산성 담지촉매와 염기성 담지촉매에서 활성도의 유지, 올레핀/파라핀 비, 탄화수소 분포, 부산물의 종류 등 제반응 특성들이 현저히 달랐다. 이러한 특이한 결과들은 양쪽 촉매에서 다른 활성종들의 존재에 기인한다고 추정된다. IR 실험 결과로 주된 활성종이 산성 담지촉매에서는 금속 또는 carbonyl clusters인 반면에 염기성 담지촉매에서는 carbonyl cluster anions이라고 판단되었다.

Iridium catalysts were prepared by converting Ir(CO)₂(acac) on acidic supports(γ-Al₂O₃, NaY) and basic supports(MgO, Basic Zeolite). The samples were used as catalysts for CO hydrogenation at 120 atm, 200-325℃ and H₂/CO feed molar ratios of 0.5-3.0. Ir catalysts supported on acidic support and on basic support showed markedly different catalytic performance in activity maintenance, olefin/paraffin product ratio, hydrocarbon distribution, and by-product species. These unique results are believed to be due to the presence of different active species on both catalysts. The IR spectra suggested that predominant iridium species in the catalysts supported by the acidic supports were metallic or carbonyl clusters, whereas those of the catalysts supported by the basic supports were carbonyl cluster anions.