Sol-gel supported catalysts containing a platinum group

Abstract

Described is a sol-gel supported catalyst comprising: (i) a first metal oxide selected from the group consisting of silicon oxide, aluminum oxide, titanium oxide, zirconium oxide and mixtures thereof; (ii) a second metal oxide selected from the group consisting of oxides of the elements of groups 4, 5, 6, 7, 11, 12, 13, 14, the iron group (atomic numbers 26 to 28), the rare-earth metals (atomic numbers 58 to 71) and mixtures thereof; and (iii) a metal selected from the group consisting of platinum metals, compounds of platinum metals (atomic numbers 44 to 46 and 77 and 78) and mixtures thereof. The sol-gel supported catalyst is prepared by: (a) providing a sol-gel comprising (i), (ii) and (iii); (b) aging the sol-gel to obtain an aged sol-gel; (c) drying the aged sol-gel to obtain said catalyst; and (d) optionally annealing the dried catalyst obtained in step (c).

1 . Catalysts containing 
 (i) an oxide of the elements silicon, aluminium, titanium, zirconium or a mixture of oxides of these elements,    (ii) one or more co-catalytic metal oxides from groups 4, 5, 6, 7, 11, 12, 13, 14, the iron group (atomic numbers 26 to 28) or the rare-earth metals (atomic numbers 58 to 71), and    (iii) one or more platinum metals or one or more compounds of platinum metals (atomic numbers 44 to 46 and 77 and 78) in an amount 0.01 to 15 wt. %, calculated as platinum metal and with respect to the total weight of catalyst,    which are obtained by preparing a gel from one or more suitable precursor(s) of the components mentioned under (i) and (ii) and the platinum metal component (iii), ageing, drying and optionally, annealing the gel.    
     
     
         2 . Process for preparing an organic carbonate by reacting an aromatic hydroxy compound with carbon monoxide and oxygen in the presence of catalysts in accordance with  claim 1 , a quaternary ammonium or phosphonium salt and a base.