Presentación de Resultados 26.08.2014
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Transcript of Presentación de Resultados 26.08.2014
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MICROWAVE
ASSISTED LIMONENEPOXIDATION
Daniela Jurado BetancurHctor Daniel Molina Eraso
Johnathan A. Ortega Meneses
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Some generalities about the umicrowaves
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The main advantages of microwave assisorganic synthesis
Faster reaction: the reactions are completed in few minutes instead of hou
Better yield and higher purity: less formation of side product are obmicrowave irradiation, and the product is recovered in higher yield. Consethe purification step is faster and easier.
Reproducibility:precise control of reaction parameters, such as temperatand power. This leads always to reproduce the same reaction conditions
Easy to use:all the reactors and software are very easy to use and all reaceasily moved from conventional to microwave heating.
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The solvent
The same solvent that is usually used in the conventional reaction can also microwave heating.
Polar solvents couple well with microwaves and reach high temperaturtime.
Non-polar solvents are transparent to microwaves.
If it is obtained a non-polar mixture, a different treatment must be done.
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Microwave at constant temperature - Microwave p
The microwave program when constant temperature is needed, usually costeps:
The ramp to reach the target temperature.
To keep the temperature for the desired reaction time
To avoid overheating the reactor, the maximum heating time for a reaction
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The ramp to reach the target temperatu
Small amount (up to 30 mL): the increasing of the temperature can be fix25C/min.
Large amount (more than 30 mL): the first step needs to be longer. In tadvised an increase of 10C/min
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Microwave power
The value of the maximum microwave power depends on the amount of sathe number of reaction vessel.
Up to 30 mL of volume and/or up to three vessels, 400-500 Watt of microwenough to heat the reaction mixture.
When large volume or more than three reactors are used, its better to uvalue of power (about 700-800 watt).
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If the temperature is not following the designed temperature profile, uheating time and/or increase the power.
If during the heating ramp the temperature overshoots, reduce themicrowave power of about 100-150 Watt.
If a very fast increase of temperature is noticed during the ramp-streaction (80-100C/min), immediately stop the microwave program. Proreagent is highly reactive and the efficient microwave heating createxothermic effect in the reaction
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Microwave at constant power
A microwave program at constant power can be used, but only with an open
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Which chemistry is not suitable for micro
Reactions that are extremely exothermic should not be performed in the in
In those cases, the experiment can be performed at low concentration solution).
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Table 1. Typical reaction conditVariable Conditions [1] Conditions [2] Co
Time 24 h - Temperature 33 - 38 C 25 - 50 C
Catalyzer 0,1 g 0,04 g
Limonene 0,5 g 2 mmol
H2O2 0,83 g 0,46 g (30 wt.% in water)
Acetonitrile 3,2 g 3.0 ml
Flask Volume 8 ml 25 ml
[1] Barrera Z., R.; Villa de P, A. L.; Montes de Correa, C. Kinetic Modeling of Limonene Epoxidation over PW
Eng. Chem. Res.(2009), 48,647653.
[2] Villa de P, A. L.; Taborda, F.; Montes de Correa, C. Kinetics of Limonene Epoxidation by Hydrogen Perox
Amberlite.J. Mol. Catal. A(2002), 185, 269.
[3] Barrera Z., R.; Villa de P, A. L.; Montes de Correa, C.; Williams, C. T. In situ Fourier transform infrared spe
studies of limonene epoxidation over PW-Amberlite.Applied Catalysis A: General365 (2009) 4247.
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Effects of the initial concentrations already k
1. At a given time limonene conversion increased with the amou
catalyst.
2. The conversion decreases with the increase in limonene conc
3. The conversion of limonene increased with the amount of oxid
4. Water enhances the conversion of limonene.
5. The addition of epoxide delays the time of reaction. Epoxide p
catalyst.
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Table 2. Bibliographical research of the micrconditions in the organic synthesis.
Reaction Microwave Conditions Reference
Synthesis of
monoglycerylcetyldimethylammonium from
3-chloro-1,2-propanediol (CP) and N,N-
dimethylhexadecylamine (DMHA) in 2-
propanol solvent and in solvent-free
conditions
T: 95 C, 130 C, 185 C
Time: 30 min, 30 min, 6 min.
Maximal power: 200 W
Satoshi H., Motoki F., Koji T., MasahMicrowave specific effects in o
proposed model from the solve
monoglycerylcetyldimethylam
Chemical Physics Letters
synthesis of nanocomposite polymers of -
cyclodextrin (-CD) and nitrogen-doped
carbon nanotubes (N-CNTs)
Time: 10 min, 15 min, 30 min.
Constant microwave power
output of 700 W.
Sello P., Edward N., Bhekie M.,
Microwave-induced synthesis o
doped carbon nanotube
nanocomposites for water purifiChemistry of the Earth 67
Styrene epoxidation reaction with molecular
O2 as an oxidant over a sulfated CoY-
doped ZrO2 solid catalyst
T: 120 C
Time: 30 min.
Non-pulsed power supply of
400 W
Beena T., Basha S. (2009). Mic
epoxidation of styrene with molec
CoYZrO2 solid catalyst. Cataly
11, 114117
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Table 2. Bibliographical research of the micrconditions in the organic synthesis.
Reaction Microwave Conditions Reference
Extraction of phenolic-compounds in
Myrcus Leaves
(300-900 W)
Dahmoune F., Nayak B., Moussi K., Rem(2014). Optimization of microwave-ass
polyphenols fromMyrtus communis L
chemestry 585-595.
Epoxidation of Styrene with O2 (400 and 800 W)
Tyagi B., Shaik B., Bajaj H.C. (2009). Mic
epoxidation of styrene with molecular O2ZrO2 solid catalyst, Catalysis communic
Epoxidation for Styrene with H2O2 30 min
Guangjian W., Zhengwang L., Yiwu L., Gu
X., Lei W. (2008). Epoxidation of styren
peroxide over Mn- Ti- Al-MCM -41 mole
microwave irradiation. Chinese journal o
1159-1164.
Oxidation of acenaphthenequinone to
1,8-naphthalic anhydride by hydrogen
peroxide
T: 60C
Time: 1 h
The initial reaction power
was set at 400 W
Shidokht N., Khashayar G. (2014). Solven
effects on oxidation of aromatic -dik
Industrial and Engineering Ch
Synthesis of polydextrose using glucose
and sorbitol as substrates; water and
phosphoric acid as initiator and catalyst.
T: 120 C
Time: 2 minutes
Constant microwave
power output of 999 W
Haisong W., Yonghui S., Guowei L
microwave-assisted synthesis of po
identification of structure and functio
Polymers 113, 225230
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Table 3. Bibliographical research for another
Solvent Reference
Dicloromethane
Chloroformed
THF
Selective epoxidation of (+)-limonene employing methyltrioxorhenium
Journal of Molecular Catalysis A: Chemical 358 (2012) 1591
DicloroethaneApplication of complex heteropolytungstates in limonene epoxidatio
biphasic medium. Catalysis Today107108 (2005) 230234
Acetonitrile
Clean limonene epoxidation using Ti-MCM-41 catalyst.Applied C
General 287 (2005) 227235.
Advance in the study of limonene epoxidation with H2O2catalyzed
complex heteropolytungstates. Catalysis Communications26 (2012
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Table 4. Experimental activities prog
Activity Date Objec
Catalyst Synthesis August 25th and 26th
To know the e
procedure to s
catalyst and
applic
Catalyst Characterization Between September 1st and 4th.
To analyze how
could be the per
catalyst when the
plac
Reaction without microwaves August 26th and 27th To make a com
reaction yields a
which could
participation of tReaction assisted by microwaves Between September 1st and 4th.
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Additional References
Favretto L. (2004). Basic Guidelines for Microwave Organic Chemistry ApMilestone Srl.