scholarly journals EFFECT OF PROPELLER MIXER TURNS NUMBER ON THE SULFIDES OXIDATION RATE IN THE OIL PHASE IN A MIXING REACTOR

2019 ◽  
Vol 20 (9-10) ◽  
pp. 79-83
Author(s):  
R. E. Lipantyev ◽  
V. P. Tutubalina
Keyword(s):  
Hydrogen Peroxide ◽  
Rotation Number ◽  
Oxidation Rate ◽  
Reaction Rate ◽  
Acid Catalyst ◽  
Oil Fraction ◽  
Sulfides Oxidation ◽  
Propeller Mixer

The effect of the rotation number of the propeller mixer on the concentration of sulfoxide sulfur in the oil fraction of Arlan oil during the oxidation of this fraction sulfides with hydrogen peroxide along with an acid catalyst, a mixture of formic and sulfuric acids in a mixing reactor, was studied. The dependences of the concentration of sulfoxide sulfur in the oil fraction and the reaction rate of the oxidation of the fraction sulfides to sulfoxides are obtained experimentally depending on the intensity of heterogeneous blend mixing in the blending reactor. 

Understanding the risks and rewards of using 50% vs. 10% strength peroxide in pulp bleach plants

TAPPI Journal ◽  
2018 ◽  
Vol 17 (11) ◽  
pp. 601-607
Author(s):  
Alan Rudie ◽  
Peter Hart
Keyword(s):  
Hydrogen Peroxide ◽  
Reaction Rate ◽  
The Other ◽  
Mechanical Pulp ◽  
Engineering Controls ◽  
Point Of Use ◽  
Process Failure

The use of 50% concentration and 10% concentration hydrogen peroxide were evaluated for chemical and mechanical pulp bleach plants at storage and at point of use. Several dangerous occurrences have been documented when the supply of 50% peroxide going into the pulping process was not stopped during a process failure. Startup conditions and leaking block valves during maintenance outages have also contributed to explosions. Although hazardous events have occurred, 50% peroxide can be stored safely with proper precautions and engineering controls. For point of use in a chemical bleach plant, it is recommended to dilute the peroxide to 10% prior to application, because risk does not outweigh the benefit. For point of use in a mechanical bleach plant, it is recommended to use 50% peroxide going into a bleach liquor mixing system that includes the other chemicals used to maintain the brightening reaction rate. When 50% peroxide is used, it is critical that proper engineering controls are used to mitigate any risks.

Chinazolinderivate durch Cyclodehydrierung von N-(2-substituierten Aryl)-Piperidinen / Quinazoline Derivatives by Cyclodehydrogenation of N-(2-Substituted Aryl)-Piperidines

1999 ◽  
Vol 54 (12) ◽  
pp. 1577-1588 ◽  
Author(s):  
H. Möhrle ◽  
M. Jeandrée
Keyword(s):  
Oxidation Rate ◽  
Reaction Rate ◽  
Product Yield ◽  
Spiro Compounds ◽  
Quantitative Yield ◽  
Cyclic Nitrones ◽  
Quinazoline Derivatives ◽  
Electron Withdrawal

Dehydrogenation of the N-[2-(aminocarbonyl)phenyl]piperidines 1 -5 using Hg(II)-EDTA, generated the quinazolinones 6 -9 . Increasing size of the 4-substituent in the piperidine decreased the oxidation rate and the product yield.N-[2-(Hydroxyiminomethyl)phenyl]piperidines 18-22 showed a different behaviour. While 18 with H g(II)-EDTA in water produced the oxime lactam 24 in quantitative yield, the 4- substituted piperidines 19-21 caused not only a lower reaction rate but also an altered product pattern. The double dehydrogenation to lactams was reduced and the cyclic nitrones, formed by two electron withdrawal, became dominant. From the spiro compounds 21 and 22, solely the quinazoline-N-oxides 29 and 30 resulted. The mechanism of the reactions is discussed.

Kinetics of the oxidation of diphenyl sulfide with hydrogen peroxide catalyzed by sodium metavanadate

1982 ◽  
Vol 60 (7) ◽  
pp. 848-852 ◽  
Author(s):  
Yoshiro Ogata ◽  
Kazushige Tanaka
Keyword(s):  
Hydrogen Peroxide ◽  
Rate Constant ◽  
Reaction Rate ◽  
Catalytic Amount ◽  
Probable Mechanism ◽  
Initial Concentration ◽  
Sodium Metavanadate ◽  
Low Concentration ◽  
Diphenyl Sulfide ◽  
Kinetics Of

The oxidation of diphenyl sulfide (Ph2S) by hydrogen peroxide in the presence of a catalytic amount of sodium metavanadate (NaVO3) has been studied kinetically by means of iodometry of hydrogen peroxide. The reaction rate is expressed as: v = k[NaVO3]st[Ph2S]2, when the concentration of catalyst is very low and [Ph2S]0/[H2O2]0 > 2, where []st and []0 mean stoichiometric and initial concentration, respectively. The effective oxidant may consist of polymeric as well as monomeric peroxyvanadate in view of the effect of concentration of catalyst on the rate. The main oxidizing species at low concentration of catalyst seems to be diperoxyvanadate VO5−. The rate constant k2 in v = k2[Ph2S]2 tends to decrease with initial concentration of H2O2, which is present in excess of the catalyst. A probable mechanism for the oxidation is discussed.

Photocatalysed Oxidation of Toxic Organics

1987 ◽  
Vol 19 (3-4) ◽  
pp. 381-390 ◽  
Author(s):  
M. Brett Borup ◽  
E. Joe Middlebrooks
Keyword(s):  
Hydrogen Peroxide ◽  
Ultraviolet Radiation ◽  
Organic Compounds ◽  
Hydroxyl Radicals ◽  
Reaction Rate ◽  
Oxidation Process ◽  
Dimethyl Phthalate ◽  
First Order ◽  
Toxic Organics ◽  
Catalyzed Oxidation

The feasibility of treating water contaminated by two toxic organic compounds with an ultraviolet light catalyzed oxidation process using hydrogen peroxide as an oxidant is investigated. In this process hydrogen peroxide is decomposed by ultraviolet radiation producing hydroxyl radicals. The hydroxyl radicals will then oxidize organic compounds via a complex chain of radical reactions. Tests showed that this photooxidation process could successfully remove isophorone and dimethyl phthalate from contaminated waters. A reaction rate expression which adequately describes the process was developed. The reaction rate was found to be first order with respect to hydrogen peroxide concentration, zero order with respect to organic concentration and a function of ultraviolet radiation intensity. The reaction did not exhibit autocatalytic characteristics.

scholarly journals Kinetic spectrophotometric determination of Bi(III) based on its catalytic effect on the oxidation of phenylfluorone by hydrogen peroxide

2009 ◽  
Vol 74 (8-9) ◽  
pp. 977-984
Author(s):  
Sofija Rancic ◽  
Snezana Nikolic-Mandic
Keyword(s):  
Hydrogen Peroxide ◽  
Spectrophotometric Determination ◽  
Reaction Rate ◽  
Catalytic Effect ◽  
Limit Of Detection ◽  
Kinetic Method ◽  
Limit Of Quantification ◽  
Kinetic Spectrophotometric ◽  
Good Agreement

A new reaction was suggested and a new kinetic method was elaborated for determination of Bi(III) in solution, based on its catalytic effect on the oxidation of phenyl-fluorone (PF) by hydrogen peroxide in ammonia buffer. By application of spectrophotometric technique, a limit of quantification (LQ) of 128 ng cm-3 was reached, and the limit of detection (LD) of 37 ng cm-3 was obtained, where LQ was defined as the ratio signal: noise = 10:1 and LD was defined as signal 3:1 against the blank. The RSD value was found to be in the range 2.8-4.8 % for the investigated concentration range of Bi(III). The influence of some ions upon the reaction rate was tested. The method was confirmed by determining Bi(III) in a stomach ulcer drug ('Bicit HP', Hemofarm A.D.). The obtained results were compared to those obtained by AAS and good agreement of results was obtained.

A Oxidative Desulfurization System for Model Oil with Hydrogen Peroxide in the Presence of Solid Acid Catalyst

2013 ◽  
Vol 699 ◽  
pp. 68-71 ◽  
Author(s):  
Liang Wang ◽  
Zi Zhen Li ◽  
Chun Hu Li ◽  
Li Juan Feng
Keyword(s):  
Hydrogen Peroxide ◽  
Solid Acid ◽  
Solid Acid Catalyst ◽  
Oxidative Desulfurization ◽  
Acid Catalyst ◽  
Oxidizing Agent ◽  
Model Compounds ◽  
Model Oil ◽  
System Water ◽  
Oxidative System

Oxidative desulfurization of model oil was conducted in emulsion oxidative system (water –in-oil [W/O]) using hydrogen peroxide as the oxidizing agent, N-methyl-2-pyrrolidone (NMP) and water as extractive solvent, span60 as surfactant. The system was evaluated for oxidative desulfurization of BT, DBT and 4.6-DMDBT using hydrogen peroxide as oxidant and exhibit excellent activities in oxidative desulfurization of model compounds.

An Investigation into the Conversion of Propylene Glycol to 2,4-dimethyl-1,3-dioxolane over an Acid Catalyst Using Gas Chromatography

2013 ◽  
Vol 850-851 ◽  
pp. 82-85
Author(s):  
Zuo You Zhang ◽  
Hui Chen ◽  
Xia Li ◽  
Zhao Hui Yang ◽  
Bao Chen Liang
Keyword(s):  
Aqueous Solution ◽  
Reaction Rate ◽  
Acid Catalyst ◽  
Reaction Rate Constant ◽  
Order Reaction ◽  
Molar Ratio ◽  
Temperature Reaction ◽  
Gas Chromatograph ◽  
Second Order Reaction ◽  
Operational Parameters

In the presence of an acid catalyst, PG react reversibly with acetaldehyde to form 2,4-dim-ethyl-1,3-dioxolane (24DMD). The effects of different operational parameters on PG conversion had been analyzed in paper, parameters included temperature, reaction time, amount of catalyst and aqueous acetaldehyde/PG molar ratio. Under optimal condition, 85% conversion of PG in aqueous solution was achieved within 180 min of reaction. The analysis of PG was conducted by gas chromatograph. Furthermore, reaction followed the second-order reaction kinetics, and the reaction rate constant was found to be 29.68min-1.

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