Investigation of the liquid phase desorption of n-paraffins from CaA and MgA zeolites

Abstract

1. The basic principle of the liquid-phase desorption of n-dodecane and n-pentadecane from the cavities of CaA and MgA zeolites with binder were investigated, using n-octane as the displacer. It was established that the desorption of these hydrocarbons proceeds effectively at a temperature of 200–300°C and a volume velocity of delivery of the displacer of about 2 h−1. The working adsorption capacity of the zeolite with respect to n-paraffins is 6–7% by weight in this case. 2. It was found that when MgA zeolite is used, the rate of desorption of n-pentadecane is 20–30% higher than in the case of CaA zeolite. 3. It was established that two-fold dilution of the n-paraffin-displacer by a nonabsorbable hydrocarbon leads to a relatively small decrease in the indices of desorption: a 10–20% decrease in the working adsorption capacity of CaA zeolite with respect to n-dodecane and n-pentadecane, with a simultaneous 20% increase in the consumption of the desorbant.