L. Lietti et E. Tronconi, MECHANISTIC ASPECTS OF THE HIGHER ALCOHOL SYNTHESIS OVER UNPROMOTED ZNCRO - 1-PROPANOL FLOW MICROREACTOR STUDY, Journal of molecular catalysis, 94(3), 1994, pp. 335-346
Mechanistic aspects of the higher alcohol synthesis (HAS) over a ZnCrO
sample are investigated by flow-microreactor experiments of 1-propano
l. Results indicate that the catalyst can promote a number of chemical
functions including hydrogenation/dehydrogenation, 'normal' and 'reve
rsal' aldolic-type condensation, ketonization, alpha-addition, dehydra
tion. On comparing the data with those obtained over a K-promoted samp
le it appears that the alkali dopant does not affect the reactivity of
ZnCrO towards hydrogenation/dehydrogenation and 'normal' aldolic-type
condensation, is essential for 'reversal' aldolic-type condensation a
nd alpha-addition, favors ketonization and essentially suppresses the
dehydration function. Thus the alkali promoter, besides playing a cruc
ial role in the C-1 --> C-2 step, significantly affects the chain grow
th mechanisms involving C-2+ oxygenates and effectively preserves oxyg
enate molecules towards the production of undesired hydrocarbons by de
hydration.