[asfrallego]

Hello there.

I am handling an adsorption of CO2 into alumina support impregnated with DEA in a fixed bed reactor. The adsorption reaction is modelled as CO2+2DEA-->product1+product2+heat (arrhenius behaviour).

The mixture species involves as bulk (co2, n2, o2, steam) and site species (dea, prod1 and prod2). The support does not have any effect on the reaction.

First I launch a simulation with no reaction to initialize a preliminar flow with no CO2. Then I turn on the transient and surface reaction equations and set up CO2 to target value at inlet. After some iterations, CO2 seems to not enter in the volume.

I try to set up a CO2 flow as initial solution and then activates the reaction. The reaction rate, heat of reaction, DEA coverage and products coverage evolves accordingly as expected with time. But CO2 concentration does not vary as long as it does not flow. Seems to be 'freezed'.

If you guys have any trick or you have handled this before, please answer me. Any suggestion will be greatfull accepted.