C. Montassier et al., DEACTIVATION OF SUPPORTED COPPER-BASED CATALYSTS DURING POLYOL CONVERSION IN AQUEOUS-PHASE, Applied catalysis. A, General, 121(2), 1995, pp. 231-244
Degradations and cyclodehydration of polyols in aqueous solution were
studied on copper deposited on charcoal unmodified or modified by addi
tion of chloride and a second metal (Pt or Au). These catalysts had pr
operties very close to those of Raney copper based catalysts. Their de
activation was studied in a dynamic flow three-phase reactor. Sinterin
g of copper particles, surface oxidation and copper(I) hydroxide dehyd
ration were responsible for the deactivation of the unmodified Cu/C. I
n the cases of modified Cu/C, decrease of the cyclodehydration selecti
vity was attributed to the loss of chloride. Addition of chloride ions
to the polyol solution to be converted increased the cyclodehydration
selectivity but strongly decreased the activity.