Hydroxylation of Phenol with Hydrogen Peroxide over the Ti-MWW Catalyst in the Presence of Acetonitrile

2011 ◽  
Vol 14 (2) ◽  
Author(s):  
Agnieszka Wróblewska ◽  
Grzegorz Wójtowicz ◽  
Edyta Makuch
Keyword(s):  
Hydrogen Peroxide ◽  
Molar Ratio ◽  
Phenol Hydroxylation ◽  
Technological Parameters ◽  
Hydroxylation Of Phenol

AbstractThis work presents the results of phenol hydroxylation with hydrogen peroxide over the Ti-MWW catalyst. The studies were carried out under autogenic pressure and in the presence of acetonitrile as a solvent. The influence of the following technological parameters on the course of hydroxylation was examined: the temperature in the range of 100-150 °C, the molar ratio of phenol/H

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.

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.

Liquid Phase Epoxidation of Allylic Compounds with Hydrogen Peroxide at Autogenic and Atmospheric Pressure over Mesoporous Ti- MCM-48 Catalyst

2009 ◽  
Vol 12 (2) ◽  
Author(s):  
Agnieszka Wróblewska ◽  
Eugeniusz Milchert
Keyword(s):  
Hydrogen Peroxide ◽  
Liquid Phase ◽  
Atmospheric Pressure ◽  
Allyl Alcohol ◽  
Molar Ratio ◽  
Technological Parameters ◽  
Liquid Phase Epoxidation

AbstractThe epoxidation of allylic compounds: allyl alcohol, methallyl alcohol and methallyl chloride to corresponding epoxides: glycidol, 2-methylglycidol and 2-methylepichlorohydrin with hydrogen peroxide over Ti-MCM-48 catalyst has been studied. The epoxidation was carried out with 30 wt% hydrogen peroxide in methanol as a solvent under autogenic pressure (in autoclave) and at atmospheric pressure in a glass reactor. The optimal technological parameters and regions of advantageous changes of: temperature, the molar ratio allylic compound/H

scholarly journals Epoxidation of natural limonene extracted from orange peels with hydrogen peroxide over Ti-MCM-41 catalyst

2018 ◽  
Vol 20 (1) ◽  
pp. 1-6
Author(s):  
Agnieszka Wróblewska ◽  
Piotr Miądlicki ◽  
Edyta Makuch ◽  
Natalia Benedyczak
Keyword(s):  
Hydrogen Peroxide ◽  
Raw Material ◽  
Molar Ratio ◽  
Technological Parameters ◽  
Orange Peels ◽  
Renewable Raw Material ◽  
Catalyst Content ◽  
Environmentally Friendly Process ◽  
Derivatives Of ◽  
Mcm 41

Abstract The paper presents the oxidation of natural limonene (extracted from waste orange peels) by 60 wt% hydrogen peroxide, in the presence of Ti-MCM-41 catalyst and in methanol as the solvent. The aim of the research was to develop the most favorable technological parameters for the process of limonene oxidation (temperature, molar ratio of limonene to hydrogen peroxide, methanol concentration, Ti-MCM-41 catalyst content and reaction time) by analyzing changes in the main functions describing this process: the conversion of limonene, selectivities of appropriate products, the conversion of hydrogen peroxide and the effective conversion of hydrogen peroxide. The process is environmentally friendly process and it uses renewable raw material - limonene and a safe oxidant -hydrogen peroxide. During the study, very valuable oxygenated derivatives of limonene were obtained: 1,2-epoxylimonene, its diol, carvone, carveol, and perillyl alcohol. These compounds are used in medicine, cosmetics, perfumery, food and polymers industries.

Copper-modified TS-1 catalyzed hydroxylation of phenol with hydrogen peroxide as the oxidant

RSC Advances ◽  
2016 ◽  
Vol 6 (103) ◽  
pp. 101071-101078 ◽  
Author(s):  
Guoqiang Wu ◽  
Jianhui Xiao ◽  
Lei Zhang ◽  
Wenjun Wang ◽  
Yanping Hong ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Phenol Hydroxylation ◽  
Hydroxylation Of Phenol ◽  
Hydroxylation Reaction

The Cu2+ species and framework Ti of the Cu/TS-1-2 catalyst can promote the phenol hydroxylation reaction.

Catalytic Epoxidation of Allyl Alcohol with Hydrogen Peroxide under Autogenic Pressure over Ti-MWW Catalyst

2011 ◽  
Vol 14 (1) ◽  
Author(s):  
Agnieszka Wróblewska ◽  
Anna Fajdek
Keyword(s):  
Hydrogen Peroxide ◽  
Allyl Alcohol ◽  
Molar Ratio ◽  
Technological Parameters ◽  
Catalytic Epoxidation

AbstractThe influence of the technological parameters (temperature (20-100 °C), the molar ratio of allyl alcohol/H

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 Bactericidal effect of hydrogen peroxide is prevented by the lactoperoxidase-thiocyanate system under anaerobic conditions

1980 ◽  
Vol 29 (3) ◽  
pp. 1190-1192
Author(s):  
J Carlsson
Keyword(s):  
Hydrogen Peroxide ◽  
Bactericidal Effect ◽  
Molar Ratio ◽  
Anaerobic Conditions ◽  
Streptococcus Sanguis

Streptococcus sanguis and Peptostreptococcus anaerobius were exposed to various combinations of the components of the lactoperoxidase-thiocyanate-hydrogen peroxide system. The bactericidal effect of hydrogen peroxide was prevented under anaerobic conditions by lactoperoxidase together with thiocyanate, but not by lactoperoxidase or thiocyanate alone. Thiocyanate was effective already at a molar ratio to hydrogen peroxide of 1:100.

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