Analogues of the active and inactive sodium carbonate

The reactivity of the anhydrous carbonates of alkaline metals with sulphur dioxide has been studied experimentally in dependence both on the nature of the cation and on the way of preparation of the anhydrous carbonate. The carbonates were prepared either by thermal decomposition of hydrogen carbonates or by thermal dehydration of carbonate hydrates. The carbonates of lithium, sodium, potassium, rubidium and caesium have been investigated. Kinetic measurements were carried out in a flow reactor in the integral regime at 423 K under atmospheric pressure, with a gas containing 0.2 vol.% of sulphur dioxide and 2.0 vol.% of water vapour in the nitrogen as a carrier gas. The reactivities have been compared on the basis of time dependence of the conversion of carbonate to sulphite.

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Thermal Decomposition of Nitrated Tri-n-Butyl Phosphate in a Flow Reactor

ISRN Chemical Engineering ◽

10.5402/2012/193862 ◽

2012 ◽

Vol 2012 ◽

pp. 1-9 ◽

Cited By ~ 6

Author(s):

Lalit K. Patil ◽

Vilas G. Gaikar ◽

Shekhar Kumar ◽

U. Kamachi Mudali ◽

R. Natarajan

Keyword(s):

Thermal Decomposition ◽

Atmospheric Pressure ◽

Flow Reactor ◽

Degradation Products ◽

Reaction Pathway ◽

Operating Conditions ◽

Purex Process ◽

Power Law Model ◽

Reaction Products ◽

Instrumental Methods

Tri-n-butyl phosphate (TBP) is a universal nuclear extractant, commercially used in the PUREX process for the last 60 years. However, it is prone to nitration and thermal degradation, and as a consequence a red-oil event may be initiated under several operating conditions resulting in severe pressurization of vessel/cell if venting is inadequate. In this work, an attempt was made to understand the reaction pathway of thermal decomposition of nitrated TBP in a flow reactor at atmospheric pressure. Many reaction products were identified and quantified by instrumental methods like HPLC-RI and GC-TCD. The experimental data was analysed with a power law model and the apparent rate constants were estimated. The activation energy for thermal decomposition of nitrated TBP, assuming an Arrhenius type of temperature dependency, was estimated to be 47.39 ± 0.25 kJ·mol−1. The effect of both varying temperature and concentration of nitric acid on conversion of TBP into degradation products and products distribution was experimentally studied. Based on the experimental observations, a reaction mechanism framework for thermal decomposition of nitrated TBP is proposed.

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Kinetics of the catalytic hydrodesulphurization reaction system; hydrogenolysis of thiophene

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19802728 ◽

1980 ◽

Vol 45 (10) ◽

pp. 2728-2741 ◽

Cited By ~ 7

Author(s):

Pavel Fott ◽

Petr Schneider

Keyword(s):

Atmospheric Pressure ◽

Active Sites ◽

Flow Reactor ◽

Kinetic Equations ◽

Reaction System ◽

Reaction Products ◽

Molybdenum Catalyst ◽

Cobalt Molybdenum Catalyst ◽

Kinetics Of ◽

Reaction Schemes

Kinetics have been studied of the reaction system taking place during the reaction of thiophene on the cobalt-molybdenum catalyst in a gradientless circulation flow reactor at 360 °C and atmospheric pressure. Butane has been found present in a small amount in the reaction products even at very low conversion. In view of this, consecutive and parallel-consecutive (triangular) reaction schemes have been proposed. In the former scheme the appearance of butane is accounted for by rate of desorption of butene being comparable with the rate of its hydrogenation. According to the latter scheme part of the butane originates from thiophene via a different route than through hydrogenation of butene. Analysis of the kinetic data has revealed that the reaction of thiophene should be considered to take place on other active sites than that of butene. Kinetic equations derived on this assumption for the consecutive and the triangular reaction schemes correlate experimental data with acceptable accuracy.

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Thermocatalytic Hydrodeoxygenation and Depolymerization of Waste Lignin to Oxygenates and Biofuels in a Continuous Flow Reactor at Atmospheric Pressure

ACS Sustainable Chemistry & Engineering ◽

10.1021/acssuschemeng.0c02102 ◽

2020 ◽

Vol 8 (35) ◽

pp. 13195-13205 ◽

Cited By ~ 2

Author(s):

Swathi Mukundan ◽

Daria Boffito ◽

Abhijit Shrotri ◽

Luqman Atanda ◽

Jorge Beltramini ◽

...

Keyword(s):

Atmospheric Pressure ◽

Continuous Flow ◽

Flow Reactor ◽

Continuous Flow Reactor

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Preparations, sulphinate coordination, and thermal decomposition of some bismuth triarenesulphinates

Australian Journal of Chemistry ◽

10.1071/ch9722107 ◽

1972 ◽

Vol 25 (10) ◽

pp. 2107 ◽

Cited By ~ 17

Author(s):

GB Deacon ◽

GD Fallon

Keyword(s):

Thermal Decomposition ◽

Acetic Acid ◽

Sulphur Dioxide ◽

Glacial Acetic Acid ◽

The Other

Bismuth triarenesulphinates, Bi(02SR)3 [R = Ph, p-MeC6H4, p-ClC6H4, 2,4,6-(Me2CH)3C6H2, and p-MeCONHC6H4], have been prepared by reaction of bismuth triacetate with the appropriate arenesulphinio acids in glacial acetic acid, and the first two compounds have also been obtained by reaction of triphenyl-bismuth with the appropriate mercuric arenesulphinates. The sulphur-oxygen stretching frequencies of the bismuth sulphinates are indicative of O-sulphinate coordination, and the compounds are considered to be polymeric with bridging O-sulphinate groups and six-coordinate bismuth. Thermal decomposition of Bi(O2SR)3 (R = Ph, p-MeC6H4, or p-CIC6H4) under vacuum gave the corresponding triarylbismuth compounds and sulphur dioxide, the preparation of tri-p-chlorophenylbismuth being accompanied by formation of di-p-chlorophenyl sulphone and S-p-chlorophenyl p-chlorobenzenethiosulphonate. Pyrolysis of the other triarenesulphinates did not yield organobismuth compounds.

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Synthesis of a Novel Structure Carbon Nanocoils and their Application in Photo Diode Devices

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1064.89 ◽

2014 ◽

Vol 1064 ◽

pp. 89-94

Author(s):

Mohammed Ibrahim Mohamed

Keyword(s):

Thermal Decomposition ◽

Atmospheric Pressure ◽

Cylindrical Shape ◽

The Novel ◽

Stainless Steel Mesh ◽

Forward Current ◽

Novel Structure ◽

Catalytic Thermal Decomposition ◽

Tunneling Recombination ◽

Preliminary Study

In this paper, the novel structure of carbon nanocoils were synthesized successfully by catalytic thermal decomposition of acetylene in CVD reactor under inert atmospheric pressure. Fe as a catalyst coated alumina beads used as substrate , both were placed inside a cylindrical shape stainless steel mesh SSC and located at the mid of CVD reactor. Preliminary study of application of prepared carbon nanocoil in synthesis of photodiode showed that the photodiode has a good rectification and the forward current obeys to tunneling-recombination model.

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Flow Structure and Heat Transfer in Stagnation Flow CVD Reactor

2010 14th International Heat Transfer Conference, Volume 2 ◽

10.1115/ihtc14-22237 ◽

2010 ◽

Cited By ~ 1

Author(s):

Nasir Memon ◽

Yogesh Jaluria

Keyword(s):

Heat Transfer ◽

Flow Structure ◽

Atmospheric Pressure ◽

Gas Flow ◽

Flow Reactor ◽

Chemical Vapor ◽

Design Parameters ◽

Stagnation Flow ◽

Inlet Length ◽

The Impact

An experimental study is undertaken to investigate the flow structure and heat transfer in a stagnation flow Chemical Vapor Deposition (CVD) reactor at atmospheric pressure. It is critical to develop models that predict flow patterns in such a reactor to achieve uniform deposition across the substrate. Free convection can negatively affect the gas flow as cold inlet gas impinges on the heated substrate, leading to vortices and disturbances in the normal flow path. This experimental research will be used to understand the buoyancy-induced and momentum-driven flow structure encountered in an impinging jet CVD reactor. Investigations are conducted for various operating and design parameters. A modified stagnation flow reactor is built where the height between the inlet and substrate is reduced when compared to a prototypical stagnation flow reactor. By operating such a reactor at certain Reynolds and Grashof numbers it is feasible to sustain smooth and vortex free flow at atmospheric pressure. The modified stagnation flow reactor is compared to other stagnation flow geometries with either a varied inlet length or varied heights between the inlet and substrate. Comparisons are made to understand the impact of such geometric changes on the flow structure and the thermal boundary layer. In addition, heat transfer correlations are obtained for the substrate temperature. Overall, the results obtained provide guidelines for curbing the effects of buoyancy and for improving the flow field to obtain greater film uniformity when operating a stagnation flow CVD reactor at atmospheric pressure.

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Atmospheric-Pressure Pulsed Discharge Plasma in a Slug Flow Reactor System for the Synthesis of Gold Nanoparticles

ACS Omega ◽

10.1021/acsomega.0c02217 ◽

2020 ◽

Vol 5 (28) ◽

pp. 17679-17685

Author(s):

Motoki Yamada ◽

Wahyudiono ◽

Siti Machmudah ◽

Hideki Kanda ◽

Yaping Zhao ◽

...

Keyword(s):

Gold Nanoparticles ◽

Atmospheric Pressure ◽

Slug Flow ◽

Discharge Plasma ◽

Flow Reactor ◽

Reactor System ◽

Pulsed Discharge ◽

Pulsed Discharge Plasma

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Synthesis and study of diaboleïte

Mineralogical Magazine and Journal of the Mineralogical Society ◽

10.1180/minmag.1968.283.036.03 ◽

1968 ◽

Vol 36 (283) ◽

pp. 933-939 ◽

Cited By ~ 4

Author(s):

R. E. Winchell ◽

H. E. Wenden

Keyword(s):

Water Vapour ◽

Atmospheric Pressure ◽

Stable Phase ◽

Line Position ◽

Natural Mineral ◽

X Ray ◽

Partial Pressures ◽

Cell Dimensions ◽

Natural And Synthetic

SummaryDiaboleïte has been synthesized between 25 and 100° C at atmospheric pressure and approximate water vapour partial pressures of 14·7 lb/in2. Under similar conditions at 170° C cumengéite appears to be the stable phase produced from a diaboleïte composition. Synthetic diaboleïte is much simpler morphologically than the natural mineral but the hemimorphic symmetry is more clearly demonstrated morphologically in the artificial specimens. A comparison of X-ray powder data for natural and synthetic diaboleïte shows almost exact detailed correspondence in line position and intensity between 0 and 180° 2θ. The cell dimensions obtained from X-ray powder data are a 5·869 ± 0·002 Å and c 5·495 ± 0·003 Å.

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