Adsorptive Separation of Ethanol Blended Gasoline on Zeolites

Abstract

Various types of zeolites were evaluated for the adsorptive separation of ethanol and gasoline in ethanol blended gasoline. Mixed solution of ethanol and n-heptane was used as a model fuel. Adsorption selectivities of zeolites for ethanol and n-heptane were measured by a pulse testing method at 80 . These properties were dependent on the framework structures, exchangeable cations and Si/Al atomic ratios of zeolites. The adsorption capacities of zeolites for ethanol and n-heptane were evaluated by a continuous flow adsorption testing method at 80 . Zeolites with the FAU type structure (Na-Y and H-Y) showed higher adsorption capacities compared to the other types of zeolites. Adsorption strength of ethanol on zeolites was evaluated by a temperature programmed desorption method. Ethanol molecules adsorbed on Na-Y and H-Y were desorbed by heat treatment at around 300 , but ethanol adsorbed on H-Y was partially dehydrated because of zeolite acidity.

Octane-On-Demand: Onboard Separation of Oxygenates from Gasoline

“…Similarly, in 2014 Mukoyama attempted application of commercially available zeolites to selectively adsorb ethanol from gasoline. Whereas the hydrophilic zeolites adsorbed a large amount of ethanol at 80 °C, the presence of acidic residues within the zeolite inhibited desorption, rendering the use of the zeolites studied infeasible …”

“…Whereas the hydrophilic zeolites adsorbed a large amount of ethanol at 80 °C, the presence of acidic residues within the zeolite inhibited desorption, rendering the use of the zeolites studied infeasible. 76 The advantage of using a solid sorbent comes with a penalty. In the case of EDA-SAMMS, the underlying silica framework contributes to mass and volume, lowering reactive volumetric site density.…”