Conclusions
In this study, we demonstrate the feasibility of binderless zeolite X
pellets synthesis using the one-pot synthesis method. Precursors with
different synthesis periods were fully characterized by multiple
techniques to investigate both the aging and crystallization mechanisms,
and to derive the crystallization kinetics. According to our results,
the formation of 4R and 6R in aging are through effective linking among
diffused Al species and dissolved Si species. Subsequently, zeolite X is
crystallized through reorganization of β cages with D6R. In addition, we
predict the adsorption capacity and interaction energy of 1-henexe
adsorption using ion-exchanged zeolite X with different ion species and
degrees of exchange via GCMC simulation. Mg-NaX and Ca-NaX present
higher 1-hexene uptake, and Co-NaX, Ni-NaX, Cu-NaX and Zn-NaX show
enhanced adsorption capacity and increased binding affinity with degree
of ion-exchange. All these data strongly suggest that the post-synthesis
ion-exchanged binderless zeolite X samples we reported here have
promising future to be applied as sorbents for the olefin/paraffin
separation.