Process description, rhodium-tpp

LPO process. Propene hydroformylation can be done with a rhodium triphenylphosphine catalyst giving a linearity ranging from 60 to 96 % depending on the phosphine concentration. At very high phosphine concentration the rate is low, but the linearity achieves its maximum value. The commercial process (Union Carbide Corporation, now Dow Chemicals) operates presumably around 30 bar, at 120 °C, at high triphenylphosphine concentrations, and linearities around 92%. The estimated turnover frequency is in the order of only 300 mol(product).mol 1 (Rh).h Low ligand 

In the presence of carbon monoxide this rhodium catalyst has no activity for hydrogenation and the selectivity based on starting material is virtually 100%. The butanal produced contains no alcohol and can be converted both to butanol and to other products as desired. 

5 Two-phase process, tppts Ruhrchemie/Rhone-Poulenc 

The tppts process has been commercialised by Ruhrchemie (now Celanese), after the initial work conducted by workers at Rhone-Poulenc, for the production of butanal from propene. Since 1995 Hoechst (now Celanese) also operates a hydroformylation plant for 1-butene. The partly isomerised, unconverted butenes are not recycled but sent to a reactor containing a cobalt catalyst. The two-phase process is not suited for higher alkenes because of the 

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