Development of system for selecting optimal zeolite–solvent combination for liquid chromatography: I. Constructing a database of solute sorption amounts

We are developing a system that selects the optimal combination of zeolite and solvent for liquid chromatography. As the first stage of system development, a database of solute sorption amounts for various combinations of zeolites and solvents was constructed. The sorption capacity of zeolites was considered according to four aspects: zeolite structure, compensation cation type, Si/Al ratio, and solute material group. As for zeolite structure, solute sorption was strongest for ∗BEA zeolite among the three examined zeolite types (Y, ∗BEA, and mordenite). As for the compensation cation type of a zeolite, sorption strength increased in the sequence H > Na > K among the three investigated cation types. Sorption was found not to depend on the Si/Al ratio because of the stronger effects of zeolite structure and solvent properties. Lastly, in regard to the solute material group, no dependence was found on the investigated zeolite characteristics; the higher the polarity of the solute and the lower polarity of the solvent, the higher was the sorption strength of the solute.

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► Zeolite adsorption capacity was considered according to four aspects.
► Solute adsorption was strongest for ∗BEA zeolite among Y, ∗BEA, and mordenite.
► Adsorption was stronger in the sequence H > Na > K of zeolite cation type.
► Adsorption did not depend on Si/Al ratio.
► Higher solute polarity, lower solvent polarity gave stronger solute adsorption.