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1
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Oxidation of hexafluoropropylene to hexafluoropropylene oxide using oxygen

100%
Łągiewczyk M., Czech Z.
Polish Journal of Chemical Technology
|
2010
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vol. 12
|
issue 2
1-3
EN
A method for pressure oxidation of hexafluoropropylene (HFP) to hexafluoropropylene oxide (HFPO), using oxygen, is presented. Oxidation was achieved in a batch-fed reactor at temperature range between 130 to 170°C. The influence of temperature and kind of solvents, such as 1,2,2-trichloro-1,1,2-trifluoroethane (CFC-113) and carbon tetrachloride on the yield of HFPO and the course of oxidation was investigated in preliminary studies. The maximum HFPO yield of approximately 83% was noticed.
2
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Epoxidation of 2-buten-1-ol over Ti-MCM-41 and Ti-MCM-48 titanium silicalite catalysts

100%
Wróblewska A., Ławro E., Milchert E.
Polish Journal of Chemical Technology
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2007
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vol. 9
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issue 3
1-4
EN
The results of the epoxidation of 2-buten-1-ol with 30 wt% hydrogen peroxide have been presented. As a solvent methanol was used. The process was carried out over the titanium silicalite catalysts: Ti-MCM-41 and Ti-MCM-48. The influence of temperature (20 - 120°C), the molar ratio of CRA/H2O2 (5:1 - 5:1), methanol concentration (5 - 90 wt%), catalyst concentration (0.1 - 5.0 wt%) and the reaction time (30 - 300 min) was investigated. The obtained results were used for the determination of optimum conditions of running the epoxidation process of 2-buten-1-ol.
3
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Catalytic activity of hexagonal MoO3modified with silver, palladium and copper

100%
Trach Y. B., Makota O. I., Bulgakova L. V., Sviridova T. V., Sviridov D. V.
Open Chemistry
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2015
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vol. 13
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issue 1
EN
Catalytic activity of solvothermally-synthesized hexagonal molybdenum trioxide (h-MoO3) in epoxidation of 1-octene by tert-butyl hydroperoxide and the effect of deposition of metal (Ag, Pd, Cu) nanoparticles on the properties of catalyst have been investigated. It has been shown that silver-modified MoO3 demonstrates the highest catalytic activity and selectivity in the reaction of 1,2-epoxyoctane formation, whereas MoO3 modified with Pd nanoparticles exhibits worse catalytic performance than bare MoO3; by contrast, copper-modified MoO3 does not catalyze the epoxidation reaction. The Ag/MoO3 catalyst was also found to be active in the reaction of 1-octene oxidation by molecular oxygen at the initial stage of the oxidation process.
4
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Application of the design of experiments in the epoxidation process of 1,5,9-cyclododecatriene

100%
Lewandowski G., Ćwirko J.
Polish Journal of Chemical Technology
|
2007
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vol. 9
|
issue 4
68-71
EN
An influence of the molar ratio of cis, trans, trans-1,5,9-cyclododecatriene to tert-butyl hydroperoxide, the concentration of the catalyst and the reaction time on the performance of the epoxidation process of cis, trans, trans-1,5,9-cyclodecatriene with tert-butyl hydroperoxide at the presence of molybdenum hexacarbonyl Mo(CO)6 was examined. Examinations were performed using statistical methods of the design of experiments. A mathematical model describing the influence of the parameters on conversion cis, trans, trans-1,5,9-cyclododecatriene was obtained. An analysis of the data and rests was performed and an optimal value of conversion of cis, trans, trans-1,5,9-cyclododecatriene was established.
5
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Oxidation of hexafluoropropylene with molecular oxygen

100%
Meissner E., Wróblewska A.
Polish Journal of Chemical Technology
|
2007
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vol. 9
|
issue 1
20-22
EN
The results of the oxidation of hexafluoropropylene (HFP) to hexafluoropropylene oxide (HFPO) have been presented. The oxidation was carried out in an autoclave within the range of temperatures of 120 - 170°C and in the presence of an organic solvent (carbon tetrachloride). Molecular oxygen was used here as an oxidizing agent. The influence of: the molar ratio of HFP/O from 13.4 to 4.09:1, the process temperature, the addition of inert gas (nitrogen) from 4 to 18 atm and the periodical dosing of oxygen were investigated. The functions describing the process were: the conversion of HFP and the yield of HFPO in relation to HFP consumed. The presented process is very interesting owing to a wide application of HFPO.
6
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Comparison of the methods of the phase transfer catalysis and hydroperoxide in the epoxidation of 1,5,9-cyclododecatriene

88%
Lewandowski G.
Polish Journal of Chemical Technology
|
2007
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vol. 9
|
issue 3
101-104
EN
The process of the epoxidation of cis, trans, trans-1,5,9-cyclododecatriene (CDT) to 1,2-epoxy-5,9-cyclododecadiene (ECDD) with the 30% aqueous hydrogen peroxide under the phase transfer conditions and with tert-butyl hydroperoxide under the homogeneous conditions was investigated. Onium salts such as Aliquat® 336, Arquad® 2HT, methyltrioctylammonium bromide and the Na2WO4/H3PO4 catalyst system are very active under the phase transfer catalysis (PTC) conditions for the selective epoxidation of cis, trans, trans-1,5,9-cyclododecatiene (PTC method). These catalytic systems were found to be as active and selective as the homogeneous phase system Mo(CO)6/TBHP (hydroperoxide method).
7
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Epoxidation of 1,5,9-cyclododecatriene with H2O2in the presence of tungstophosphoric acid (H3PW12O40)

88%
Wołosiak A., Lewandowski G.
Polish Journal of Chemical Technology
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2010
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vol. 12
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issue 3
40-44
EN
The influence of the technological parameters on the epoxidation of 1,5,9-cyclododecatriene (CDT) to 1,2-epoxy-5,9-cyclododecadiene (ECDD) by the phase-transfer catalysis method (PTC) in the presence of tungstophosphoric heteropolyacid (H3PW12O40) and hydrogen peroxide as the oxidizing agent has been presented. The phase-transfer catalyst was Aliquat® 336 (methyltrioctylammonium chloride). The epoxidation of CDT to ECDD in the PTC system proceed under the relatively mild condition: low temperature, lack of solvent, short reaction time.The effect of: the mixing velocity, the molar ratio of CDT:H2O2 and H2O2:H3PW12O40, the nature of the solvent and its concentration, was studied. The most advantageous technological parameters were: the mixing rate 400 - 600 rpm, the molar ratio of CDT:H2O2 = 3:1 - 1.5:1, the molar ratio of H2O2:H3PW12O40 = 200:1 - 400:1, the temperature 40 - 50°C, solvent: dichloromethane or lack of the solvent, dichloromethane concentration: 10 - 50 vol%, reaction time 35 - 50 min. The application of the above-mentioned parameters allows to achieve the yield of 44 - 47% ECDD in relation to introduced CDT.
8
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Efficiency of selected phase transfer catalysts for the synthesis of 1,2-epoxy-5,9-cyclododecadiene in the presence of H2O2/H3PW12O40as catalytic system

88%
Lewandowski G.
Polish Journal of Chemical Technology
|
2013
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vol. 15
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issue 3
96-99
EN
The results of the studies on the influence of the phase transfer catalyst on the epoxidation of (Z,E,E)-1,5,9-cyclododecatriene (CDT) to 1,2-epoxy-5,9-cyclododecadiene (ECDD) in the H2O2/H3PW12O40 system by a method of phase transfer catalysis (PTC) were presented. The following quaternary ammonium salts were used as phase transfer catalysts: methyltributylammonium chloride, (cetyl)pyridinium bromide, methyltrioctylammonium chloride, (cetyl)pyridinium chloride, dimethyl[dioctadecyl(76%)+dihexadecyl(24%)] ammonium chloride, tetrabutylammonium hydrogensulfate, didodecyldimethylammonium bromide and methyltrioctylammonium bromide. Their catalytic activity was evaluated on the basis of the degree of CDT and hydrogen peroxide conversion and the selectivities of transformation to ECDD in relation to consumed CDT and hydrogen peroxide. The most effective PT catalysts were selected based on the obtained results. Among the onium salts under study, the epoxidation of CDT with hydrogen peroxide proceeds the most effectively in the presence of methyltrioctylammonium chloride (Aliquat® 336) and (cetyl)pyridinium chloride (CPC). The relatively good results of CDT epoxidation were also achieved in the presence of Arquad® 2HT and (cetyl)pyridinium bromide
9
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Optimization of the epoxidation process of (1Z,5E,9E)-1,5,9-cyclododecatriene to 1,2-epoxy-(5Z,9E)-5,9-cyclododecadiene withtert-buthyl hydroperoxide - the influence of technological parameters on the hydroperoxide conversion

75%
Lewandowski G., Rytwińska E., Milchert E.
Polish Journal of Chemical Technology
|
2007
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vol. 9
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issue 3
105-107
EN
The optimization studies of the epoxidation process of (1Z,5E,9E)-1,5,9-cyclododecatriene (CDT) with tert-buthyl hydroperoxide (TBHP) over the molybdenum catalyst Mo(CO)6 were performed. The reaction was examined in terms of a uniform-rotatable design. Three factors were analyzed: the reaction time, CDT:TBHP molar ratio, and the molar concentration of the catalyst (Mo(CO)6). According to the design 20 experiments were performed at the constant temperature of 70°C.
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