Optimization of a Ti-MWW Catalysed Phenol Hydroxylation Process

2012 ◽  
Vol 15 (2) ◽  
Author(s):  
Agnieszka Wróblewska
Keyword(s):  
Hydrogen Peroxide ◽  
Reaction Time ◽  
Organic Compounds ◽  
Design Method ◽  
Uniform Design ◽  
Molar Ratio ◽  
Phenol Hydroxylation ◽  
Statistical Experimental Design ◽  
Experimental Design Method ◽  
Good Substitute

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.

The Process of Phenol Hydroxylation in the Water Solution and over the Ti-MWW Catalyst

2012 ◽  
Vol 10 (1) ◽  
Author(s):  
Agnieszka Wróblewska
Keyword(s):  
Hydrogen Peroxide ◽  
Reaction Time ◽  
Raw Materials ◽  
Water Solution ◽  
Uniform Design ◽  
Mathematical Optimization ◽  
Cost Effective ◽  
Molar Ratio ◽  
Phenol Hydroxylation ◽  
Technological Parameters

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.

scholarly journals The utilization of the mesoporous Ti-SBA-15 catalyst in the epoxidation of allyl alcohol to glycidol and diglycidyl ether in the water medium

2015 ◽  
Vol 17 (4) ◽  
pp. 23-31 ◽  
Author(s):  
Agnieszka Wróblewska ◽  
Edyta Makuch ◽  
Małgorzata Dzięcioł ◽  
Roman Jędrzejewski ◽  
Paweł Kochmański ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Reaction Time ◽  
Allyl Alcohol ◽  
Water Solution ◽  
Reaction Medium ◽  
Diglycidyl Ether ◽  
Molar Ratio ◽  
Water Medium ◽  
Catalyst Content ◽  
Allyl Alcohol Epoxidation

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.

scholarly journals A facile and effective method for preparation of 2.5-furandicarboxylic acid via hydrogen peroxide direct oxidation of 5-hydroxymethylfurfural

2017 ◽  
Vol 19 (1) ◽  
pp. 11-16 ◽  
Author(s):  
Shuang Zhang ◽  
Long Zhang
Keyword(s):  
Hydrogen Peroxide ◽  
Reaction Time ◽  
Oxidation Mechanism ◽  
Molar Ratio ◽  
Alkaline Condition ◽  
Optimal Parameters ◽  
Direct Oxidation ◽  
Reaction Parameters ◽  
Alkaline Conditions ◽  
Furandicarboxylic Acid

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.

scholarly journals Interesterification of Egg-Yolk Phosphatidylcholine with p-Methoxycinnamic Acid Catalyzed by Immobilized Lipase B from Candida Antarctica

Catalysts ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1181
Author(s):  
Magdalena Rychlicka ◽  
Anna Gliszczyńska
Keyword(s):  
Reaction Time ◽  
Design Method ◽  
Immobilized Lipase ◽  
Reaction Medium ◽  
Solvent System ◽  
Novozym 435 ◽  
Molar Ratio ◽  
Binary Solvent ◽  
Methoxycinnamic Acid ◽  
Substrate Molar Ratio

The p-methoxycinnamic acid (p-MCA) is one of the most popular phenylpropanoids, the beneficial impact of which on the human health is well documented in the literature. This compound has shown many valuable activities including anticancer, antidiabetic, and neuro- and hepatoprotective. However, its practical application is limited by its low bioavailability resulting from rapid metabolism in the human body. The latest strategy, aimed at overcoming these limitations, is based on the production of more stability in systemic circulation bioconjugates with phospholipids. Therefore, the aim of this research was to develop the biotechnological method for the synthesis of phospholipid derivatives of p-methoxycinnamic acid, which can play a role of new nutraceuticals. We developed and optimized enzymatic interesterification of phosphatidylcholine (PC) with ethyl p-methoxycinnamate (Ep-MCA). Novozym 435 and a binary solvent system of toluene/chloroform 9:1 (v/v) were found to be the effective biocatalyst and reaction medium for the synthesis of structured p-MCA phospholipids, respectively. The effects of the other reaction parameters, such as substrate molar ratio, enzyme dosage, and reaction time, on the degree of incorporation of p-MCA into PC were evaluated by use of an experimental factorial design method. The results showed that substrate molar ratio and biocatalyst load have significant effects on the synthesis of p-methoxycinnamoylated phospholipids. The optimum conditions were: Reaction time of three days, 30% (w/w) of Novozym 435, and 1/10 substrate molar ratio PC/Ep-MCA. Under these parameters, p-methoxycinnamoylated lysophosphatidylcholine (p-MCA-LPC) and p-methoxycinnamoylated phosphatidylcholine (p-MCA-PC) were obtained in isolated yields of 32% and 3% (w/w), respectively.

Using a Statistical Experimental Design Method to Confirm the Optimization of Al/Al Doped ZnO Double Layers

2020 ◽  
Vol 49 (10) ◽  
pp. 5667-5673
Author(s):  
Shao-Hwa Hu ◽  
Yen-Sheng Lin ◽  
Yi-Ting Lin ◽  
Shui-Hsiang Su ◽  
Li-Chun Wu
Keyword(s):  
Experimental Design ◽  
Design Method ◽  
Double Layers ◽  
Statistical Experimental Design ◽  
Experimental Design Method ◽  
Doped Zno

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
Keyword(s):  
Hydrogen Peroxide ◽  
Reaction Time ◽  
Glycidyl Ether ◽  
Diglycidyl Ether ◽  
Methanol Concentration ◽  
Molar Ratio ◽  
Oxidizing Agent ◽  
Aqueous Hydrogen Peroxide ◽  
Allyl Glycidyl Ether ◽  
Catalyst Content

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%.

Iodination of Organic Compounds with Elemental Iodine in the Presence of Hydrogen Peroxide in Ionic Liquid Media

2008 ◽  
Vol 61 (12) ◽  
pp. 946 ◽  
Author(s):  
Jasminka Pavlinac ◽  
Kenneth K. Laali ◽  
Marko Zupan ◽  
Stojan Stavber
Keyword(s):  
Hydrogen Peroxide ◽  
Ionic Liquid ◽  
Organic Compounds ◽  
Molar Ratio ◽  
Liquid Media ◽  
Reaction Conditions ◽  
Solid Form ◽  
Elemental Iodine ◽  
Solvent Free Reaction

Iodo-transformations using the reagent system I2/H2O2 were studied in the water miscible ionic liquid (IL) 1-butyl-3-methyl imidazolium tetrafluoroborate (bmimBF4) and in water immiscible IL, 1-butyl-3-methyl imidazolium hexafluorophosphate (bmimPF6). Two different forms of H2O2 as mediators of iodination were investigated, namely 30% aq. H2O2 and urea-H2O2 (UHP) in solid form. The role of the oxidant during the course of a reaction could be distinguished based on the amount of reagent required for the most efficient transformation. Two types of iodo-functionalizations through an electrophilic process were observed depending on the structure of the substrates. Whereas ring iodination took place in the case of dimethoxy- and trimethoxy-benzenes, with arylalkyl ketones the alkyl group α to the carbonyl was regioselectively iodinated. The results were further evaluated in comparison with iodination using the reagent system I2/H2O2 in water as medium, and under solvent-free reaction conditions, in terms of efficiency, selectivity, mechanism, and the ‘green’ aspects. The reusability/recycling of water immiscible bmimPF6 was investigated for 1,3,5-trimethoxy benzene (1b), which required a 1/0.5/0.6 molar ratio of substrat/I2/oxidant, and for 1,2,3-trimethoxy benzene (1f), which required a 1/1/1 ratio for complete iodine introduction. In addition, the efficiency of iodination was tested by varying the substrates, and employing the recycled hydrophobic IL bmimPF6.

scholarly journals Optimization of an Industrial Medium from Molasses for Bioethanol Production Using the Taguchi Statistical Experimental-Design Method

Fermentation ◽  
2019 ◽  
Vol 5 (1) ◽  
pp. 14 ◽  
Author(s):  
Farshad Darvishi ◽  
Nooshin Abolhasan Moghaddami
Keyword(s):  
Experimental Design ◽  
Taguchi Method ◽  
Yeast Strain ◽  
Design Method ◽  
Yeast Cells ◽  
Statistical Experimental Design ◽  
Bioreactor Culture ◽  
Bioethanol Production ◽  
Anaerobic Conditions ◽  
Experimental Design Method

The production of bioethanol as a clean liquid fuel in a cost-effective way is highly desired by global energetics. Sugar beet molasses is a renewable and cheap substrate for the production of biotechnological products. Therefore, the aim of the current study was the optimization of an industrial medium from molasses for bioethanol production using the Taguchi statistical experimental-design method. First, the growth rate of yeast cells and the amount of ethanol produced by the Saccharomyces cerevisiae strain sahand 101 were investigated in aerobic and aerobic–anaerobic conditions. The yeast strain produced 8% (v/v) bioethanol in a medium containing molasses with 18% Brix in aerobic–anaerobic conditions. The main factors of the medium, including molasses, ammonium sulfate, urea, and pH, were optimized for the increase of bioethanol production by the Taguchi method. Bioethanol production reached 10% (v/v) after optimization of the medium in flask culture. The yeast strain produced 11% (v/v) bioethanol in the bioreactor culture containing the optimized medium, which is an acceptable amount of bioethanol produced from molasses at the industrial scale. The results showed that the Taguchi method is an effective method for the design of experiments aiming to optimize the medium for bioethanol production by reducing the number of experiments and time.

Clean Synthesis of 2-Methylglycidol over a Novel Titanosilica Catalyst - Ti-MWW under Autogenic Pressure

2012 ◽  
Vol 10 (1) ◽  
Author(s):  
Anna Fajdek ◽  
Agnieszka Wróblewska ◽  
Eugeniusz Milchert
Keyword(s):  
Reaction Time ◽  
Organic Compounds ◽  
Catalyst Concentration ◽  
Methanol Concentration ◽  
Molar Ratio ◽  
Solvent Concentration ◽  
Technological Parameters ◽  
Clean Synthesis ◽  
Stirring Intensity

In this work the epoxidation of methallyl alcohol (MAA) with 30 wt% H2O2 over the Ti-MWW catalyst has been studied. The significant parameters for the MAA epoxidation were established as temperature (20-120°C), the molar ratio of MAA/H2O2 (1:1-5:1), methanol (solvent) concentration (5-90 wt%), Ti-MWW catalyst concentration (0-5.0 wt%), reaction time (5-300 min) and intensity of stirring (0-500 rpm). The process of MAA epoxidation was carried out the most effective at temperature of 100°C, the molar ratio of MAA/H2O2=1:1, methanol concentration of 40 wt%, the catalyst concentration of 2 wt%, the reaction time of 15 min and with the stirring intensity over 350 rpm. These the best technological parameters (mild and relatively safe) allow to obtain the selectivity of transformation to 2MG 37 mol%, the MAA conversion 52 mol%, and the selectivity of transformation to organic compounds in relation to H2O2 consumed 48 mol%.

Sign in / Sign up

Export Citation Format

Share Document