Synthesis of 2,3-butanedione over TS-1, Ti-NCl, TiMCM-41, Ti-Beta, Fe-Si, Fe-Beta and VS-1 zeolites

Article abstract of DOI:10.3390/50300610

The purpose of this work is the synthesis of 2,3-butanedione (diacetyl) by selective oxidation of 2-butanone (methyl ethyl ketone) in the presence of O₂ and H₂O₂ 30% as oxidants. All the tests were performed over several selective oxidation zeolite catalysts, synthesized and characterized in our laboratory.

Full text of DOI:10.3390/50300610

610
Molecules 2000, 5
Synthesis of 2,3-Butanedione over TS-1, Ti-NCl, TiMCM-41,
Ti-Beta, Fe-Si, Fe-Beta and VS-1 Zeolites
Andrea Beltramone, Marcos Gomez, Liliana Pierella and Oscar Anunziata
CITeQ (Centro de Investigacion y Tecnologia Quimica), Facultad Cordoba-Universidad Tecnologica
Nacional, CC36 -Suc16 (5016)- Cordoba, Argentina
Tel.\Fax: 54-351-4690585, E-mail: anunziat@sa.frc.utn.edu.ar
Abstract: The purpose of this work is the synthesis of 2,3-butanedione (diacetyl) by selec-
tive oxidation of 2-butanone (methyl ethyl ketone) in the presence of O2 and H2O2 30% as
oxidants. All the tests were performed over several selective oxidation zeolite catalysts,
synthesized and characterized in our laboratory.
Introduction
2,3-Butanedione or diacetyl, a flavor compound having a distinct buttery character accumulates
during alcoholic and malolactic fermentation of wine and beer. The synthesis of 2,3-butanedione has
been reported by heterogeneous catalysis, using Cs-K/V2O5 [1-4].
Experimental
Catalyst preparation, characterization and catalytic activity
All the samples were prepared by sol-gel method using raw amorphous SiO2/HeteroatomO2 gels.
The following reactants were used: TEOS (tetraethylorthosilicate), as source of Silicon. TiPOT (tetrai-
sopropylorthotitanate) and TNBOT (tetrabutylorthotitanate) as raw material for titanium. ferric nitrate
as source of Iron. vanadyl sulfate as source of vanadium. TPAOH (tetrapropylammonium hydroxide)
and TBAOH (tetrabutylammonium hydroxide) as template for TS-1; TEAOH (tetraethylammonium
hydroxide) for TiBEA; DTMA (dodecyltrimethylammonium bromide) for MCM-41 and HMTBOH
(N,N’-hexamethylenebis [tributylammonium hydroxide]) for NCL-1 zeolite. The final product was
filtered, washed with distilled water, dried at 110°C and calcined at 500°C for 12 h. We obtained the
following zeolites: TS-1, Fe-Si, Ti-Beta, Fe-Beta, Ti-NCL-1, Ti-MCM-41 and VS-1. The catalysts
were characterized by AA, XRD- Synchrotron, BET, FT-IR and TPD of templates [5]. The standard
reactions of oxidation of 2-butanone (methyl ethyl ketone, MEC, Sintorgan 99%) were performed in a
flow reactor using oxygen as oxidant, the results are showed in table 1. According with the dates in
table 1, the VS-1 sample is active and selective for the synthesis of 2,3-butanedione, Fe-Beta sample

611
Molecules 2000, 5
is active but the selectivity is poor. In addition, this reaction was performed in presence of
H2O2/MEK=6 and W/F=20ghmol-1 over VS-1 obtaining low conversion (7% at 200°C) but high selec-
tivity to diacetyl. The reaction products were analyzed by Gas Chromatography with a capillary AT-
Wax column of 30m and Mass Spectroscopy using a GC-MS 823.
Table 1. MEC conversion and selectivity to 2,3-butanedione using O2, over zeolites at different reac-
tion conditions.
Catalyst
O2/MEC T(°C)
W/F
Conversion
(mol%)
Selectivity to
2,3-Butanedione
(mol%)
(g.h.mol-1)
Ti-MCM-
41
1.3
250
12
3.0
25.0
Ti-NCL-1
Fe-Beta
VS-1
1.3
3.4
1.3
250
250
250
12
24
24
2.5
40.5
15.2
32.0
4.0
57.7
The influence of reaction temperature on the oxidation of 2-butanone is shown in Fig. 1. In this fig-
ure the conversion and selectivity versus temperature are plotted for VS-1 and O2 as oxidant. We can
observe that the conversion increases with temperature but the selectivity decreases notably.
45
40
35
30
25
20
15
10
5
90
80
70
60
50
40
30
20
10
0
150
200
250
300
350
400
450
Temperature (°C)
Figure 1. Activity of VS-1. O2/MEK=3.4 and W/F=24g.h.mol-1.
References and Notes
1. Jahan, I.; Kung, H. H. Ind. Chem. Res. 1992, 31, 2329.
2. Ai, M. J. Catal. 1984, 89, 413.
3. Takita, Y.; Nita, K.; Maheara, T.; Yamazoe, N.; Seiyama, T. J. Catal. 1977, 50, 364.
4. Takita, Y.; Hori, F.; Yamazoe, N.; Seiyama, T. Bull. Chem. Soc. Jpn. 1987, 60, 2757.
5. Anunziata, O.A.; Pierella, L.B.; Beltramone, A.R. Stud. Surf. Sci. Catal. 1999, 125, 523.