scholarly journals Epoxidation of allyl-glycidyl ether with hydrogen peroxide over Ti-SBA-15 catalyst and in methanol medium

2016 ◽  
Vol 18 (4) ◽  
pp. 9-14 ◽  
Author(s):  
Marika Walasek ◽  
Agnieszka Wróblewska

Abstract This work presents the studies on the epoxidation of allyl-glycidyl ether (AGE) over the Ti-SBA-15 catalyst. In these studies an aqueous hydrogen peroxide was used as an oxidizing agent and as a solvent methanol was applied. The studies on the influence the following parameters: temperature (20–80°C), molar ratio of AGE/H2O2 (1:1.5–5:1), methanol concentration (10–90 wt%), catalyst content (1–9 wt%) and reaction time (15–240 min.) were carried out and the most favourable values of these parameters were chosen (temperature 80°C, molar ratio of AGE/H2O2 = 5:1, methanol concentration 30 wt%, catalyst content 3 wt% and the reaction time 240 min.). At these conditions the functions describing the process reached the following values: the selectivity of diglycidyl ether (DGE) 9.2 mol%, the conversion of AGE 13.9 mol% and the efficiency of H2O2 conversion 89.9 mol%.

2015 ◽  
Vol 17 (4) ◽  
pp. 23-31 ◽  
Author(s):  
Agnieszka Wróblewska ◽  
Edyta Makuch ◽  
Małgorzata Dzięcioł ◽  
Roman Jędrzejewski ◽  
Paweł Kochmański ◽  
...  

Abstract This work presents the studies on the optimization the process of allyl alcohol epoxidation over the Ti-SBA-15 catalyst. The optimization was carried out in an aqueous medium, wherein water was introduced into the reaction medium with an oxidizing agent (30 wt% aqueous solution of hydrogen peroxide) and it was formed in the reaction medium during the processes. The main investigated technological parameters were: the temperature, the molar ratio of allyl alcohol/hydrogen peroxide, the catalyst content and the reaction time. The main functions the process were: the selectivity of transformation to glycidol in relation to allyl alcohol consumed, the selectivity of transformation to diglycidyl ether in relation to allyl alcohol consumed, the conversion of allyl alcohol and the selectivity of transformation to organic compounds in relation to hydrogen peroxide consumed. The analysis of the layer drawings showed that in water solution it is best to conduct allyl alcohol epoxidation in direction of glycidol (selectivity of glycidol 54 mol%) at: the temperature of 10–17°C, the molar ratio of reactants 0.5–1.9, the catalyst content 2.9–4.0 wt%, the reaction time 2.7–3.0 h and in direction of diglycidyl ether (selectivity of diglycidyl ether 16 mol%) at: the temperature of 18–33°C, the molar ratio of reactants 0.9–1.65, the catalyst content 2.0–3.4 wt%, the reaction time 1.7–2.6 h. The presented method allows to obtain two very valuable intermediates for the organic industry.


2015 ◽  
Vol 797 ◽  
pp. 347-351 ◽  
Author(s):  
Ewa Drewnowska ◽  
Agnieszka Wróblewska ◽  
Alicja Gawarecka

This work presents the research on the influence of the addition of the appropriate amounts of the inorganic salt (Na2SO4) on the reduction of the ineffective decomposition of hydrogen peroxide (H2O2) and simultaneously on the increase of the efficiency of hydrogen peroxide conversion. The studies were carried out for the epoxidation of diallyl ether to allyl-glycidyl ether with 30 wt% hydrogen peroxide on the TS-1 catalyst and in the presence of acetonitrile as the solvent. The studies were conducted in the following conditions: the temperature of 70°C, the molar ratio of diallyl ether/hydrogen peroxide = 3:1, the acetonitrile concentration of 50 wt%, the TS-1 content of 9 wt%, the reaction time of 3 hours, the intensity of stirring of 500 rpm and the molar ratio of hydrogen peroxide/Na2SO42:1 to 14:1 (also the results for epoxidation of diallyl ether without Na2SO4were presented)


2021 ◽  
Vol 132 (2) ◽  
pp. 983-1001
Author(s):  
Grzegorz Lewandowski ◽  
Marcin Kujbida ◽  
Agnieszka Wróblewska

AbstractThis work presents the studies on the epoxidation of 1,5,9-cyclododecatriene (CDT) with hydrogen peroxide as the oxidizing agent, under conditions of the phase transfer catalysis (PTC), and with the following catalytic system: H2WO4/H3PO4/[CH3(CH2)7]3CH3N+HSO4− (compounds were mixed at the ratio of 2:1:1). The influence of the following parameters on the course of this process was investigated: catalyst content, molar ratio of H2O2:CDT, temperature and type of solvent. The highest yield of 1,2-epoxy-5,9-cyclododecadiene (ECDD) (54.9 mol%), at the conversion of CDT reached 72.3 mol%, was obtained at the temperature of 50 °C, for the catalyst content of 0.45 mol% (in relation to the introduced CDT), for the molar ratio of H2O2:CDT 1.5:1, with toluene as the solvent and after the reaction time of 30 min. Considering the he obtained results and numerous applications of ECDD, further research should be developed to provide a more efficient and environmentally friendly way of obtaining this compound. Graphic abstract


Catalysts ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1402
Author(s):  
Agnieszka Wróblewska ◽  
Marcin Kujbida ◽  
Grzegorz Lewandowski ◽  
Adrianna Kamińska ◽  
Zvi C. Koren ◽  
...  

This work presents the results of our research on the epoxidation of 1,5,9-cyclododecatriene (CDT) with hydrogen peroxide over the Ti-MCM-41 catalyst. The influence of the following parameters on the course of the process was investigated: temperature, CDT:H2O2 molar ratio, solvent composition and its type, and catalyst content. The highest selectivity of CDT transformation to 1,2-epoxy-5,9-cyclododecadiene (ECDD)—approximately 100 mol%, the highest yet reported—was obtained at the CDT conversion of 13 mol% and with the following parameter values: a catalyst content of 5 wt%; a molar ratio of CDT:H2O2 = 2; isopropyl alcohol (i-PrOH) as the solvent, with a composition of 80 wt% in the reaction mixture; a temperature of 80 °C; and a reaction time of 240 min. The highest conversion of CDT (37 mol%) was obtained at the ECDD selectivity of 56 mol% and using the following process parameters: a catalyst content of 5 wt%; a molar ratio of CDT:H2O2 = 0.5; i-PrOH used as the solvent, with solvent composition of 80 wt%; a temperature of 80 °C; and a reaction time of 60 min. It should be emphasized that the CDT conversion obtained in the current study is higher (by 9 mol%) than that described in the literature on heterogeneous catalysts.


2014 ◽  
Vol 496-500 ◽  
pp. 193-197
Author(s):  
Jiang Ling Han ◽  
Hui Lu Li ◽  
Kang Chen Shao ◽  
Wen Liu

With allyl glycidyl ether and terminal hydrogen silicone oil, in certain conditions, the silicone-modified epoxy resin synthesized by the hydrosilylation reaction. This study discuss the effect of the structure and properties on the synthesized product, such as the catalyst, reaction time, reaction temperature and the C = C/Si-H molar ratio of allyl glycidyl ether and terminal hydrogen silicone oil. Infrared spectroscopy, gel permeation chromatography (GPC), epoxy value and hydrolysis chlorine of the polysiloxane-modified epoxy resin were characterized and analysized. The results show that the terminal hydrogen silicone oil-modified epoxy resin has balanced epoxy value, molecular weight and molecular weight distribution, the conversion of reactive hydrogen is the highest when the dosage of H2PtCl66H2O is 0.01% to 0.02% of reactant in weight, the molar ratio of C=C /Si-H in AGE (allyl glycidyl ether) and the terminal of hydrogen silicone oil is 4.28:1, the reaction temperature is 80°C to 85°C, reaction time is controlled in 6 hours.


2015 ◽  
Vol 17 (4) ◽  
pp. 82-87 ◽  
Author(s):  
Agnieszka Wróblewska ◽  
Edyta Makuch ◽  
Piotr Miądlicki

Abstract This work presents the studies on the oxidation of limonene with hydrogen peroxide and tert-butyl hydroperoxide (TBHP) in the presence of : TS-2, Ti-Beta, Ti-MCM-41 and Ti-MWW catalysts, at the autogenic pressure and atmospheric pressure. The examination were performed at the following conditions: the temperature of 140°C (studies in the autoclave) and 80°C (studies in glass reactor), the molar ratio of limonene/oxidant (H2O2 or WNTB) = 1:1, the methanol concentration 80 wt%, the catalyst content 3 wt%, the reaction time 3 h and the intensity of stirring 500 rpm. The analysis of the results showed that in process not only 1,2-epoxylimonene was formed but also: 1,2-epoxylimonene diol, carveol, carvone and perillyl alcohol but for 1,2-epoxylimonene obtaining the better method was the method at the autogenic pressure and in the presence of TBHP.


2017 ◽  
Vol 19 (1) ◽  
pp. 11-16 ◽  
Author(s):  
Shuang Zhang ◽  
Long Zhang

Abstract In this paper, 2,5-furandicarboxylic acid (FDCA) was efficiently prepared by the direct oxidation of 5-hydroxymethylfurfural (5-HMF) using hydrogen peroxide (H2O2) in alkaline conditions without any catalysts. The effects of reaction parameters on the process were systematically investigated and the optimal parameters were obtained as follows: molar ratio of 5-HMF:KOH:H2O2 was 1:4:8, reaction temperature and reaction time were determined as 70°C and 15 minutes, respectively. Under these conditions, the yield of FDCA was 55.6% and the purity of FDCA could reach 99%. Moreover, we have speculated the detailed oxidation mechanism of 5-HMF assisted by hydrogen peroxide in alkaline condition to synthesize FDCA.


2012 ◽  
Vol 15 (2) ◽  
Author(s):  
Agnieszka Wróblewska

AbstractsAs a result of phenol hydroxylation, two useful products can be received: hydroquinone and pyrocatechol. In this work the hydroxylation of phenol with hydrogen peroxide over the Ti-MWW catalyst has been studied. Optimization studies were performed by application of a statistical experimental design method utilizing a rotatable-uniform design. The influence of five parameters on the course of this process was examined: temperature (120-150°C), molar ratio of phenol/hydrogen peroxide (0.5-1.5), acetonitrile - solvent content (20- 50 wt%), catalyst - Ti-MWW content (8-18 wt%) and reaction time (60-120 min). The process description was based on four response functions: the conversion of phenol to organic compounds, the yield of pyrocatechol, the yield of hydroquinone and the conversion of phenol to tars. The most favourable parameters for the process of phenol hydroxylation were as follows: temperature 147-150°C, molar ratio of phenol/hydrogen peroxide 0.5-0.6, acetonitrile content 21-24 wt%, Ti-MWW content 10.3-10.6, reaction time 221-236 min. In summary, these the most favourable parameters allow one to obtain pyrocatechol with the yield of 18 mol%, hydroquinone with the yield of 20 mol%, at the conversion of phenol to organic compounds 38 mol% in relatively mild and safe conditions. These results also showed that Ti-MWWcatalyst can be a good substitute for TS-1 catalyst.


Author(s):  
Agnieszka Wróblewska

Abstract This work presents the studies on the optimization of the process of phenol hydroxylation over the Ti-MWW catalyst. The medium of the reaction was only water introduced into the rector with the 30 wt% hydrogen peroxide (oxidizing agent) and formed during the reaction from the hydrogen peroxide. For the mathematical optimization the rotatable-uniform design was used. The main investigated technological parameters were: the temperature, the molar ratio of phenol/hydrogen peroxide, the catalyst content and the reaction time. The course of the main functions describing the process were presented in the form of layer drawings. The analysis of the layer drawings allowed to establish the most beneficial parameters for this process. Studies have shown that in water solution it is best to conduct phenol hydroxylation process at: the temperature of 93-100oC, phenol/hydrogen peroxide molar ratio 0.9-1, catalyst concentration 3-3.5 wt% and during the reaction time of 55-60 minutes. Under these conditions, it is possible to achieve phenol conversion of 85 mol%, selectivity of transformation to organic compounds in relation to phenol consumed 50 mol% and the yield of hydroquinone about 19 mol%. The phenol hydroxylation method, presented in this article, is a preferred alternative to conventional solutions, as it is more environmentally and cost-effective, taking into account consumption of raw materials and energy.


1995 ◽  
Vol 50 (12) ◽  
pp. 1818-1832 ◽  
Author(s):  
Thomas Kaukorat ◽  
Ion Neda ◽  
Reinhard Schmutzler

In the reaction of N-methylaminomethylene-dimethylphosphine oxide and sulfide with diethylaminotrimethylsilane, N-methyl-N-trimethylsilyl-aminomethylene-dimethylphosphine oxide (1) and sulfide (2) were formed. These compounds were allowed to react with a series of P(III)C1 compounds to give the corresponding methylaminomethylene-bridged diphosphorus compounds (3 - 10) with phosphorus in the combination λ4P(V)/λ3P(III). In the oxidation of some of these compounds by the hydrogen peroxide-urea 1:1-adduct (NH2)2CO ·H2O2 or sulfur, the corresponding λ4P-CH2-N(Me)-λ4P-derivatives (11 - 16) were formed. Different reaction behaviour was observed depending on the substituent at λ4P or on the oxidizing agent. Reaction of 1 with trimethylsilylmethyl tetrafiuorophosphorane and with bromotriphenylphosphonium bromide furnished, besides trimethylhalosilane, the corresponding diphosphorus compounds (17 ) and (18) with phosphorus in the combination λ4P(V)/λ5P(V) (17) and λ4P(V)/λ4P(V)+ (18).Oxidation of N-diphenylphosphino-N-methyl-aminomethylene-dimethylphosphine oxide (3) by tetrachloro-o-benzoquinone led to the corresponding addition product in impure form. Reaction of 3 with hexafluoroacetone (HFA) yielded a mixture of two products which could not be separated. Both oxidation (>N-PPh2 → >N-P(:O)Ph2) and insertion of HFA into the P-N-bond (>N-PPh2 → >NC(CF3)2-O-PPh2) occurred. In the reaction of 1 with methyldichlorophosphine, both the mono- and disubstituted products, 22 and 23, were formed, independently of the reaction conditions and molar ratio of the starting compounds. The reaction of 1 with bis(diethylamino)chlorophosphine was unusual. Upon separation of both trimethylchlorosilane and dimethylaminotrimethylsilane, compounds 24 - 26 were formed, with the central phosphorus atom bearing one, two or three methylaminomethylene-dimethylphosphine oxide groups, respectively. Simultaneously, tris(diethylamino)phosphine was formed.


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