R. Feng et al. / Catalysis Communications 11 (2010) 1220–1223
1223
Table 3
Highly selective preparing DEA is still a great challenge and will
become an important target.
Influences of crystal size and surface modification on catalytic performance.
Catalyst
Temp.
/K
Press.
/MPa
NH3/
EO
LHSV
/h−1
Conv.
(/%)
Selectivity (%)
MEA+DEA
4. Conclusion
TEA
HZSM-5
HZSM-5 (C)
HZSM-5 (Si)
353
353
353
8.0
8.0
8.0
8.0
8.0
8.0
6.0
6.0
6.0
90.5
65.9
88.2
97.1
99.2
98.7
2.9
0.8
1.3
Shape-selective catalysis amination of EO based on HZSM-5 was
studied. This work reveals that Brönsted acid site plays a major role in
this reaction. To improve the selectivity of MEA and DEA, deactivation
external surface active site is an effective method. Shortened pore
passages and enriched pore mouths are beneficial to the diffusion of
reactant and product, which can largely improve the yields of MEA
and DEA.
Table 4
Influences of NH3/EO ratio on relative selectivity of MEA/DEA on HZSM-5 zeolite.
NH3/
EO
Conv.
(/%)
Selectivity (%)
MEA
Acknowledgements
DEA
TEA
4.0
5.0
6.5
8.0
9.0
95.6
96.7
98.1
99.3
99.3
47.7
53.6
58.2
69.6
72.7
42.4
40.6
36.9
27.8
25.8
9.9
5.8
4.9
2.6
1.5
This work which is supported by the National Nature Science
Foundation of China (2009CB623501), and financial support by the
China Postdoctoral Science Foundation funded project (no.
20080430601) is gratefully acknowledged.
Reaction conditions: temperature 353 K, pressure 8.0 MPa, LHSV 4.0 h−1
.
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