Conclusions
In summary, multiple-layer and mono-layer MWW zeolite nanosheets were
fabricated through the dual template synthesis strategy with
conventional HMI and long chain surfactants, in terms of multi-layered
MWW thickness or single-unit-cell thickness along the c -axis with
a large number of exposed Brønsted acid sites. This strategy works well
on a layered MWW zeolite system that simultaneously integrates exposed
Brønsted acid sites and shape-selectivity, which exhibits excellent
catalytic activity and selectivity towards 2-LAB in the alkylation
between benzene with 1-dodecene. Mechanistic insights are provided that
the superior catalytic performance originates from the raised accessible
Brønsted acid sites, enhanced molecular diffusion and solid interactions
between adsorbate and 12-MR pockets on the exterior surface. From our
investigation, it’s clear that in order to achieve higher 1-dodecene
conversion with MWW zeolite nanosheets system, a modification of the MWW
nanosheets to allow i) delamination of layered MWW zeolites into the
single-unit-cell nanosheet, ii) assembling the single-unit-cell
nanosheets into ordered multilamellar arrangement and iii) precise
control of Al species distribution in discrepant T sites must be found.
Therefore, our present work lays the foundation for catalysts design in
the future to fulfill this task, but our study already produces
regularly spaced MWW zeolite
nanosheets with harmonic Al distribution, representing an important
finding.