Art_Deco saidIsn't this the principle used with freeze-dried instant coffee?
With lyophilization (freeze drying) you freeze the product first and use vacuum to sublimate off the water. (i.e. you skip the liquid phase entirely). Or were you thinking of coffee decaffeination by supercritical fluid extraction? That uses CO2 as the working fluid.
and yes... I do
have a lyophilizer in my kitchen.