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1
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Adsorption of 1,2-dichloropropane from aqueous solution

100%
Pełech R., Milchert E.
Polish Journal of Chemical Technology
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2007
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vol. 9
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issue 2
34-36
EN
In this study dependences of the adsorption equilibrium of 1,2-dichloropropane in aqueous solution for six activated carbons (A, AG, AG5, DTO, WD-ekstra, CWZ-22) and four polymeric adsorbents (XE-563, XE-572, XE-340, XE-348) were presented. All the adsorption isotherms onto activated carbons were described by the Freundlich equation. To analyze the isotherms on the polymeric adsorbents the Langmuir-Freundlich equation was used. It was found that in the low range of the concentrations the adsorptive properties of the activated carbons are reduced in the following direction DTO>WD-ekstra>CWZ-22>AG>A>AG5. Reducing the adsorptive properties of the polymeric adsorbents states was carried out in the following order: XE-340> XE-572>XE-563>XE-348. The adsorbents XE-340, XE-572 and XE-563 have much more higher adsorptive properties than the applied activated carbons. Lower adsorptive properties of XE-348 are the result of its high surface polarity.
2
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N-hexylpyridinium bis(trifluoromethylsulfonyl)imide and Lewis acids - catalytic systems for Diels-Alder reaction

81%
Bittner B., Janus E., Milchert E.
Open Chemistry
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2011
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vol. 9
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issue 1
192-198
EN
A comparative study of the Diels-Alder reactions between cyclopentadiene (1) and dienophiles (2 a–c) in N-hexylpyridinium bis(trifluoromethylsulfonyl)imide in a temperature range of 20–45°C is reported. The reaction rate constants and activation energies were calculated. Moreover, the catalytic systems based on N-hexylpyridinium bis(trifluoromethylsulfonyl)imide and Lewis acids were tested as a reaction media to perform the Diels-Alder reaction. Yb, Y, Mg, Zn triflates and chlorides (0.005 to 0.1 mmol) were used as catalysts. The recycling of catalytic system consisted of YCl3 and ionic liquid was performed. [...]
3
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Synthesis and characteristics of titanium silicalite TS-1, Ti-Beta and Ti-MWW catalysts

81%
Wróblewska A., Fajdek A., Milchert E.
Polish Journal of Chemical Technology
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2009
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vol. 11
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issue 1
64-71
EN
The synthesis methods of the following titanium-silicalite catalysts: TS-1, Ti-Beta and Ti-MWW were presented. The results of the analyses of the catalysts by XRD, SEM and IR, UV-vis methods were also shown. A brief description of the catalytic performances of these catalysts in the oxidation process of olefins, alkenes, alcohols and aromatic compounds was presented.
4
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Utilization of waste chloroorganic compounds

81%
Myszkowski J., Milchert E., Bartkowiak M., Pełech R.
Polish Journal of Chemical Technology
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2010
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vol. 12
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issue 3
36-39
EN
Efficient methods of utilization of waste chloroorganic compounds coming from waste water and the waste streams formed e.g. in the production of vinyl chloride by dichloroethane method and in the production of propylene oxide by chlorohydrin method have been presented. First the separation of chloroorganic wastes by the adsorption methods has been described in the article. Three valuable methods of chlorocompounds utilization have been then discussed. The first one is isomerization of 1,1,2-trichloroethane to 1,1,1-trichloroethane as the valuable product with less toxicity than a substrate. The second method is ammonolysis of waste 1,2-dichloropropane and 1,2,3-trichloropropane. The third described method is chlorolysis. This method can be used for the utilization of all types of waste chloroorganics.
5
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Epoxidation of 2-buten-1-ol over Ti-MCM-41 and Ti-MCM-48 titanium silicalite catalysts

81%
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.
6
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Topical and prospective processes of acetoxylation

81%
Lewandowski G., Bartkowiak M., Milchert E.
Polish Journal of Chemical Technology
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2009
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vol. 11
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issue 4
46-51
EN
The latest acetoxylation processes have been described in this work: oxidative acetoxylation of propene to allyl acetate, acetoxylation of propene to propene glycol and its acetates, acetoxylation of methyl tert-butyl ether and oxidative acetoxylation of cyclohexene by hydrogen peroxide. Acetoxylation of 1,3-butadiene, isobutene and toluene were presented together with a short description of the acetoxylation catalysts.
7
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Dehydrochlorination of 1,3-Dichloropropan-2-Ol by Calcium and Sodium Hydroxide Solutions

81%
Krzyżanowska A., Milchert E., Bartkowiak M.
Polish Journal of Chemical Technology
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2014
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vol. 16
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issue 3
86-90
EN
The results of dehydrochlorination of 88 wt% aqueous solution of 1,3-dichloropropan-2-ol to epichlorohydrin are reported. The process was carried out in the reaction-stripping column system with a continuous removal of epichlorohydrin in the steam stream. Aqueous solutions of sodium and calcium hydroxides at concentrations in the range of 3-14 wt% were used for the dehydrochlorination. The infl uence of the type and concentration of dehydrochlorination agent on 1,3-dichloropropan-2-ol conversion, the selectivity of transformation to epichlorohydrin and by-products, and the composition of distillate and wastewater were studied.
8
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Changes in the composition of wastewater as a result of dehydrochlorination of 1,3-dichloropropan-2-ol under different process conditions

81%
Krzyżanowska A., Milchert E., Bartkowiak M.
Polish Journal of Chemical Technology
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2014
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vol. 16
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issue 1
92-96
EN
The results of dehydrochlorination of 1,3-dichloropropan-2-ol to epichlorohydrin are reported. The process ran in the reaction-stripping column system with a continuous removal of epichlorohydrin in a steam stream. The influence of 10 wt% alkali solution (NaOH, Ca(OH)2) and the method of distillate collection on the 1,3-dichloropropan-2-ol conversion, selectivity of transformation to epichlorohydrin and by-products, and the composition of wastewater have been analysed.
9
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Epoxidation of crotyl alcohol in the presence of titanium silicalite Ti-MWW catalyst - the new and friendly method of 2,3-epoxybutane-1-ol synthesis

81%
Wróblewska A., Fajdek A., Milchert E.
Polish Journal of Chemical Technology
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2010
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vol. 12
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issue 2
57-61
EN
Epoxidation of crotyl alcohol (CA) with 30 wt% hydrogen peroxide over Ti-MWW catalyst has been studied with methanol as a solvent and at autogenic pressure. The influence of temperature in the range of 20-120°C, the molar ratio of CA/H2O2 1:1-5:1, methanol concentration 5-90 wt%, Ti-MWW catalyst concentration 0.0-5.0 wt% and the reaction time 5-300 min have been studied. The main product of CA epoxidation is 2,3-epoxybutane-1-ol (2,3EB1O), a compound with many applications.
10
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The Ti-MWW catalyst - its characteristic and catalytic properties in the epoxidation of allyl alcohol by hydrogen peroxide

81%
Wróblewska A., Fajdek A., Milchert E., Grzmil B.
Polish Journal of Chemical Technology
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2010
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vol. 12
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issue 1
29-34
EN
Ti-MWW, one of the latest titanium-silicalite catalysts, has been prepared by direct hydrothermal synthesis using hexamethyleneimine as a structure-directing agent. The characteristic of the catalyst was performed by means of the following methods: XRD, SEM, IR, UV-vis and X'Ray microanalysis. The catalytic properties of Ti-MWW have been compared with those of the conventional titanium-silicalites TS-1 and TS-2 in the epoxidation of allyl alcohol with hydrogen peroxide. The process has been described by the following main functions: the selectivity of the transformation to glycidol in relation to allyl alcohol consumed, the conversions of the substrates (allyl alcohol and hydrogen peroxide) and the selectivity of the transformation to organic compounds in relation to hydrogen peroxide consumed.
11
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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

81%
Lewandowski G., Rytwińska 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
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.
12
Content available remote

Formation of environmentally friendly chloroorganic compounds technology by sewage and by-products utilization

81%
Myszkowski J., Milchert E., Paździoch W., Pełech R.
Polish Journal of Chemical Technology
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2007
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vol. 9
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issue 3
118-121
EN
The processes presented in the study enables the separation and disposal of the chloroorganic compounds as by-products from the vinyl chloride plant by using the dichlorethane method and also from the production of propylene oxide by the chlorohydrine method. The integrated purification method of steam stripping and adsorption onto activated carbon allows a complete removal and recovery of the chloroorganic compounds from waste water. Waste distillation fraction is formed during the production of vinyl chloride. 1,1,2-trichloroethane separated from the above fraction, can be processed to vinylidene chloride and further to 1,1,1-trichloroethane. 2,3-Dichloropropene, 2-chloroallyl alcohol, 2-chloroallylamine, 2-chlorothioallyl alcohol or bis(2-chloroallylamine) can be obtained from 1,2,3-trichloropropane. In the propylene oxide plant the waste 1,2-dichloropropane is formed, which can be ammonolysed to 1,2-diaminopropane or used for the production of β-methyltaurine. Other chloroorganic compounds are subjected to chlorinolysis which results in the following compounds: perchloroethylene, tetrachloromethane, hexachloroethane, haxachlorobutadiene and hexachlorobenzene. The substitution of the milk of lime by the soda lye solution during the saponification of chlorohydrine eliminates the formation of the CaCl2 waste.
13
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Mg(OTf)2+ ionic liquid - recyclable catalytic system in diels-alder reaction

81%
Bittner B., Milchert E., Janus E.
|
EN
A comparative study of Diels-Alder reaction between cyclopentadiene and dimethyl maleate in catalytic system is reported. The catalytic system was formed from ionic liquid which was made of N-hexylpyridinium bis(trifluoromethylsulfonyl)imide and magnesium trifluoromethanesulfonate. The yields, TONs, TOFs and endo:exo ratios were calculated. The optimal catalyst concentration was found in order to obtain the mixture of endo, exo isomers with the highest yields. Moreover recycling of the catalytic system consisting of Mg(OTf)2 (2 mol%) and ionic liquid was performed. The distillation was noticed to be a better product removal method than extraction by organic solvent, taking into consideration both the TON and TOF values.
14
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Influence of reduction time of copper based catalysts: Cu/Al2O3and CuCr2O4on hydrogenolysis of glycerol

81%
Wołosiak-Hnat A., Milchert E., Lewandowski G., Grzmil B.
Polish Journal of Chemical Technology
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2011
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vol. 13
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issue 4
71-76
EN
High activity of copper based catalysts for C-O bond hydro-dehydrogenation and their poor activity for C-C bond cleavage1 have prompted an attempt to apply such catalysts in the hydrogenolysis of glycerol to 1,2- and 1,3-propanediol. In the present study the influence of hydrogen reduction time of the Cu/Al2O3 and CuCr2O4 copper catalysts on glycerol conversion and selectivity of transformation to propanediols and by-products was studied. At first a general comparison was made between the commercial catalysts and those prepared by the co-precipitation method. As better results were obtained in the presence of catalysts prepared by co-precipitation, they were selected for further detailed studies of the influence of reduction time. For both prepared catalysts Cu/Al2O3 and CuCr2O4 the reduction time of 8 h was optimal. In the presence of Cu/Al2O3 catalyst the conversion of glycerol was 59.0%, selectivity of transformation to 1,2-propanediol 77.4% and selectivity to 1,3-propanediol 1.9%. In the presence of CuCr2O4 the glycerol conversion was 30.3% and selectivity to 1,2-propanediol 67.3%.
15
Content available remote

Isolation of 1,2-epoxybutane-3-ol and 2,3-epoxybutane-1-ol from post-reaction mixtures

81%
Wróblewska A., Wajzberg-Prokowska J., Ławro E., Milchert E.
Polish Journal of Chemical Technology
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2010
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vol. 12
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issue 2
29-32
EN
Attempts were made to isolate 1,2-epoxybutane-3-ol and 2,3-epoxybutane-1-ol from post-reaction mixtures left after the epoxidation of 1-butene-3-ol and 2-butene-1-ol with hydrogen peroxide by thin film distillation. From the raw mixture containing about 8.3 wt% of the epoxide at the first stage the concentration of epoxide is increased to 32 wt%. At the second stage of distillation the epoxide fraction is concentrated to about 76 wt%. After the third stage of thin film distillation the epoxide fraction of 99.6% purity can be obtained. The concentration of this fraction by azeotropic distillation with n-propanol as an azeotropic agent permits obtaining epoxide of 99.6 wt% purity.
16
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The pressure method of 1-butene-3-ol epoxidation over Ti-beta catalyst

71%
Wróblewska A., Wajzberg J., Milchert E., Grzmil B., Ziebro J.
Polish Journal of Chemical Technology
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2007
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vol. 9
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issue 2
53-56
EN
The investigations of 1-buten-3-ol (1B3O) epoxidation by 30% hydrogen peroxide over Ti-Beta catalyst were performed. The experiments were carried out under the autogenic pressure and at the presence of methanol as a solvent. The influence of the following technological parameters on the course of epoxidation: temperature (20 - 120°C), the molar ratio of 1B3O/H2O2 (0.5:1 - 5:1), methanol concentration (5 - 90 wt%.), Ti-Beta concentration (0.1 - 5.0 wt%) and the reaction time (0.5 - 5.0 h) was investigated. The main functions describing the process were: the selectivity of transformation to 1,2-epokxy-3-butanol in relation to 1B3O consumed, conversions of substrates as well as the selectivity of transformation to organic compounds in relation hydrogen peroxide consumed.
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