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ONEꢀPOT SYNTHESIS OF A NOVEL CATALYST WITH STRONG ACID SITES
381
CHO
O
OH
+
HO
O
Carbon based
solid acid
HY
Novel solid acid
Carbon based
solid acid
Sulfuric acid
Amberlystꢀ15
Sulfuric acid
HY
Amberlystꢀ15
Novel solid acid
0 10 20 30 40 50 60 70 80 90
Yield, %
0
20
40
60
80 100
Yield, %
Fig. 4. Catalytic activity of the novel solid acid based on the
carbon/silica composite for the dimerization of
styrene.
Fig. 3. Catalytic activity of the novel solid acid based on
the carbon/silica composite for the acetalization.
α
ꢀmethylꢀ
was investigated through the acetalization of benzalꢀ cient for both hydrophilic and hydrophobic acidꢀcataꢀ
dehyde and 1,2ꢀethenediol. The results showed that lyzed reactions with the activities comparable to those
the catalyst activity was stable. The yields remained of sulfuric acid. The advantages of the catalyst include
unchanged even after the sample had been recycled high acidity, large surface area, low cost and reasonꢀ
five times. Furthermore, the catalytic activity of the able thermal and chemical stability, which made the
recycled filtrate was investigated and the results novel heterogeneous catalyst an appropriate candidate
showed no activity of the filtrate, which further conꢀ for the replacement of the homogeneous catalysts in
firmed that acid sites was not removed from the surface green processes.
of the solid acid. These results support the suggestion
of a high stability of the novel solid acid.
REFERENCES
1. Anastas, P.T. and Kirchhoff, M.M., Acc. Chem. Res.
,
3.3. The Catalytic Activities for Dimerization
of ꢀMethylstyrene
2002, vol. 35, p. 686.
2. DeSimone, J.M., Science, 2002, vol. 297, p. 781.
3. Harton, B., Nature, 1999, vol. 400, p. 797.
4. Anastas, P.T. and Zimmermann, J.B., Environ. Sci.
Technol., 2003, vol. 37, p. 94A.
α
The novel solid acid based on carbon/silica comꢀ
posite was tested in the catalytic dimerization of
ꢀmethylstyrene (Fig. 4). HY zeolite with a high
α
BETsurface area exhibits relatively high activity for
the reaction, whereas Amberlystꢀ15 is also quite active
in the reaction. The hydrophobic molecule ꢀmethylꢀ
5. Clark, J.H., Acc. Chem. Res., 2002, vol. 35, p. 791.
6. Misono, M., C. R. Acad. Sci., Ser. IIc: Chim., 2000,
α
vol. 3, p. 471.
styrene could reach the acid sites on the surface of the
solid acid. However, the hydrophilic functional groups
such as SO3H, COOH, and phenolic hydroxyl (OH)
groups prevent incorporation of hydrophobic moleꢀ
7. Okuhara, T., Chem. Rev., 2002, vol. 102, p. 3641.
8. Hara, M., Yoshida, T., Takagaki, A., Takata, T., Kondo, J.N.,
Domen, K., and Hayashi, S., Angew. Chem. Int. Ed.,
2004, vol. 43, p. 2955.
9. Toda, M., Takagaki, A., Okamura, M., Kondo, J.N.,
Domen, K., Hayashi, S., and Hara, M., Nature, 2005,
vol. 438, p. 178.
10. Okamura, M., Takagaki, A., Toda, M., Kondo, J.N.,
Domen, K., Tatsumi, T., Hara, M., and Hayashi, S.,
Chem. Mater., 2006, vol. 18, p. 3039.
cules ꢀmethylstyrene into the acid site on the tradiꢀ
α
tional carbon based solid acid that shows a low BET
surface area. The novel solid acid based on carbon/silꢀ
ica composite with a high BET surface area exhibits a
remarkably high activity for the reaction. The activity
is higher than that of the conventional solid acids and
is comparable to that of sulfuric acid.
11. Liang, X., Zeng, M., and Qi, C., Carbon, 2010, vol. 48,
p. 1844.
12. Liang, X., Xiao, H., Shen, Y., and Qi, C., Mater. Lett.,
4. CONCLUSION
2010, vol. 64, p. 953.
The novel solid acid based on carbon/silica comꢀ
posite was obtained through the hydrothermal carbonꢀ
ization. The novel process was more environmentꢀ
friendly in the mild condition with little waste emisꢀ
sion and high yield. The novel solid acid was very effiꢀ
13. Nakajima, K., Okamura, M., Kondo, J.N., Domen, K.,
Tatsumi, T., Hayashi, S., and Hara, M., Chem. Mater.,
2009, vol. 21, p. 186.
14. DemirꢀCakan, R., Baccile, N., Antonietti, M., and
Titirici, M.M., Chem. Mater., 2009, vol. 21, p. 484.
KINETICS AND CATALYSIS Vol. 54
No. 3
2013