Catalyticmechanism of aceticacid synthesisfrommethanol carbonylation bylow pressure method:Catalyst: [Rh+1(CO),I]-/ CH,ICH,OH +HI→ CHI +H,0[Rh(COI] + CH,]-[CH,Rh(CO)2]3][CH,Rh(CO)2]3]→[CHCORh(CO)I][CH,CORh(CO)Is]- +CO [CH,CORh(CO),]}][CH,CORh(CO)2]]CH,COI + [Rh(CO)2]]CH,COOH + HICH,COI + H,0
▲ Catalytic mechanism of acetic acid synthesis from methanol carbonylation by low pressure method: Catalyst: [Rh+1(CO)2 I2 ] - / CH3 I CH3OH +HI CH3 I + H2O [Rh(CO)2 I2 ] - + CH3 I [CH3Rh(CO)2 I3 ] - [CH3Rh(CO)2 I3 ] - [CH3CORh(CO)I3 ] - [CH3CORh(CO)I3 ] - +CO [CH3CORh(CO)2 I3 ] - [CH3CORh(CO)2 I3 ] - CH3COI + [Rh(CO)2 I2 ] - CH3COI + H2O CH3COOH + HI
Comparison betweentwomethods (ortwocatalysts)formethanolcarbonylationComparison of reactions and properties between two catalytic system ofCarbonylrhodium-iodinand carbonylcobalt-iodinCo catalystRh catalystCatalytic system19601970TimeCompanyGermanyBASFAmericaMonsantoCH,OHCH,OHMaterialT/C210-250175-200703P /MPaProductsCH,COOH /CH,COOH /CH,COOCH3CH,COOCH3>90>99Selectivity /%
▲Comparison between two methods (or two catalysts) for methanol carbonylation Comparison of reactions and properties between two catalytic system of Carbonyl rhodium-iodin and carbonyl cobalt-iodin Catalytic system Co catalyst Rh catalyst Time 1960 1970 Company Germany BASF America Monsanto Material CH3OH CH3OH T/ ºＣ 210-250 175-200 P /MPa 70 3 Products CH3COOH / CH3COOH / CH3COOCH3 CH3COOCH3 Selectivity /% >90 >99