It has been studied the fructose to glucose isomerization using a fixe
d bed reactor and recirculation with a commercial enzyme, the inmovili
zed glucose isomerase at a temperature of 50-degrees-C. The kinetics o
f the isomerization corresponds to a pseudofirst order reversible enzi
matic reaction. It has been estimated the effectiveness factor for int
ernal materia transfer that seems to be independent of the used substr
ate concentrations, being the external materia transfer disregarding a
t the flows considered.