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Catalysis Science & Technology
DOI: 10.1039/C5CY01493J
ARTICLE
Catalysis Science &Technology
ratios and RC, they exhibited comparable reaction activity. This This was mainly attributed to the different adsorption properties and
indicated that either CTAB or TPABr could be used as an additive protective effects upon zeolites of both alkylammonium cations.
during alkaline treating ZSMꢀ11, but different CNaOH was preferred
for both additives. By the way, all tested samples had a similar hierarchical zeolites obtained from alkaline treatment in the presence
product distribution (not shown). of CTAB as well as TPABr, aided our understanding of their
Our results provided valuable insights regarding the
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J. PérezꢀRamírez et al. reported that USY and beta treated physiochemical implication, and highlighted their potential in
with NaOH and TPABr (nonꢀmicelle forming) did not lead to catalyzed reactions. Furthermore, it is very important to develop a
composites but highly crystalline hierarchical zeolites, while those sustainable approach to prepare hierarchical zeolites. In the further
prepared with NaOH and CTAB (micelle forming) displayed the work, we will take advantage of the costly zeolite removed by
composites (zeolite/OMMs) generation. The former exhibited alkaline treatment, recycle the waste streams and prevent the organic
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superior performance than the latter in the alkylation of toluene with compounds from combustion as J. PérezꢀRamírez et al. stated.
ꢀpropanol or benzyl alcohol. That was somehow different from our
work. It may be ascribed to the different intrinsic qualities of CTAB
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and TPABr and different alkaline treatment conditions, which had
evident effects on the acidity and structural properties of resultant
Acknowledgements
samples, just as MCMꢀ49 based micro–mesoporous composites and The guidance and help of Professor Yide Xu is greatly
hierarchical MCMꢀ49 zeolite with intracrystalline mesopores could appreciated.
be obtained by treating MCMꢀ49 in solution with NaOH and CTAB
3
3, 57
under different treatment conditions, respectively
. Under our
treatment conditions, the ZSMꢀ11 samples alkaline treated with
assistance of CTAB were hierarchical ZSMꢀ11 with intracrystalline
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2 | Catal. Sci. Technol.
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