The Catalytic Oxidation of Hydrocyanic Acid (II). Oxidation into Some Solid Reaction Products and the Reacting Mechanism of Oxidation.

AbstractA series of reduced-charge montmorillonites (RCM), prepared from the same parent Li-montmorillonite (Jelšový Potok, Slovakia) by heating at various temperatures (105–210°C) for 24 h, was treated with 6 m HCl at 95°C for periods up to 30 h. Reaction solutions obtained were analysed for Al, Fe, Mg and Li and the solid reaction products were investigated by FTIR spectroscopy. Both analyses provided evidence that the extent of dissolution decreased with increased amounts of Li fixed within the montmorillonite structure, i.e. with increased heating temperature. Differences in the acid dissolution process were reflected in the structural changes which occurred within the RCM samples, due presumably to different positions of fixed Li. The ethylene glycol monoethyl ether (EGME) surface areas, and XRD and HRTEM analyses of the RCM series revealed an increased amount of non-swelling layers in the samples prepared at higher temperatures, which caused a substantially slower decomposition of M7 and M8 in HCl. The calculated XRD patterns of M6 and M7 confirmed the presence of 20% and 45% pyrophyllite-like layers, respectively, in these samples. Mixed-layer pyrophyllite-like-smectite and pyrophyllite-like crystals, containing only non-swelling layers, were found in sample M8. The results confirmed that the amount of swelling layers in RCM significantly affects their dissolution rate in HCl.

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Study on Preparation of Ti Powder by Self-Propagating High-Temperature Synthesis (SHS) with Magnesiothermit Reductive Process

Materials Science Forum ◽

10.4028/www.scientific.net/msf.575-578.1086 ◽

2008 ◽

Vol 575-578 ◽

pp. 1086-1092

Author(s):

Peng Lin Zhang ◽

Tian Dong Xia ◽

Guo Dong Zhang ◽

Li Jing Yan

Keyword(s):

Reaction Rate ◽

Combustion Temperature ◽

Combustion Process ◽

Green Compact ◽

Reaction Products ◽

Technological Parameters ◽

Solid Reaction ◽

Temperature Synthesis ◽

High Temperature Synthesis ◽

Ti Powder

The combustion process of Mg-TiO2 system was preliminarily investigated from three aspects of thermodynamics, reaction kinetics and the technological parameters. The result indicates that the adiabatic temperature of Mg-TiO2 system is between 2060K and 2140K because the major existent modalities of TiO2 is the rutile and anatase, this meets the empirical criterion that the SHS reaction will be self-sustaining; The solid-solid reaction occurs at about 767K; Ti powders can be produced only when the ratio between Mg and TiO2 arrives at 2.9:1; The higher the vacuum, the more complete the reaction; The combustion temperature arrives at its peak when the pressure of green compact arrives at 250MPa; the velocity of the combustion wave increases with the augmentation of the pressure of green compact. So the proper control of the technological parameters can change the reaction temperature, reaction rate and the components of reaction products.

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Application of the Statistical Oxidation Model (SOM) to Secondary Organic Aerosol formation from photooxidation of C<sub>12</sub> alkanes

Atmospheric Chemistry and Physics ◽

10.5194/acp-13-1591-2013 ◽

2013 ◽

Vol 13 (3) ◽

pp. 1591-1606 ◽

Cited By ~ 33

Author(s):

C. D. Cappa ◽

X. Zhang ◽

C. L. Loza ◽

J. S. Craven ◽

L. D. Yee ◽

...

Keyword(s):

Formation Process ◽

Secondary Organic Aerosol ◽

Organic Aerosol ◽

Atomic Ratio ◽

Model Parameters ◽

Reaction Products ◽

Aerosol Formation ◽

Volatile Organic ◽

Oxidation Model ◽

Mechanism Of Oxidation

Abstract. Laboratory chamber experiments are the main source of data on the mechanism of oxidation and the secondary organic aerosol (SOA) forming potential of volatile organic compounds. Traditional methods of representing the SOA formation potential of an organic do not fully capture the dynamic, multi-generational nature of the SOA formation process. We apply the Statistical Oxidation Model (SOM) of Cappa and Wilson (2012) to model the formation of SOA from the formation of the four C12 alkanes, dodecane, 2-methyl undecane, cyclododecane and hexylcyclohexane, under both high- and low-NOx conditions, based upon data from the Caltech chambers. In the SOM, the evolution of reaction products is defined by the number of carbon (NC) and oxygen (NO) atoms, and the model parameters are (1) the number of oxygen atoms added per reaction, (2) the decrease in volatility upon addition of an oxygen atom and (3) the probability that a given reaction leads to fragmentation of the molecules. Optimal fitting of the model to chamber data is carried out using the measured SOA mass concentration and the aerosol O:C atomic ratio. The use of the kinetic, multi-generational SOM is shown to provide insights into the SOA formation process and to offer promise for application to the extensive library of existing SOA chamber experiments that is available.

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Possibility of continuous measurement of the pressure in the combustion front of pyrotechnic compositions producing solid reaction products

Combustion Explosion and Shock Waves ◽

10.1007/bf00785358 ◽

1991 ◽

Vol 27 (1) ◽

pp. 62-65

Author(s):

V. A. Golubev ◽

P. G. Berezhko ◽

V. F. Proskudin ◽

A. S. Malyshev

Keyword(s):

Combustion Front ◽

Continuous Measurement ◽

Reaction Products ◽

Solid Reaction ◽

Pyrotechnic Compositions

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Stability of kaolin sand from the Vyšný Petrovec deposit (south Slovakia) in an acid environment

Geologica Carpathica ◽

10.2478/v10096-012-0039-x ◽

2012 ◽

Vol 63 (6) ◽

pp. 503-512 ◽

Cited By ~ 6

Author(s):

Pentrák Martin ◽

Madejová Jana ◽

Andrejkovičová Slávka ◽

Uhlík Peter ◽

Komadel Peter

Keyword(s):

Dissolution Rate ◽

Xrd Analysis ◽

Reaction Products ◽

Solid Reaction ◽

Oh Groups ◽

High Dissolution Rate ◽

Acid Environment ◽

Mir Spectra ◽

Gradual Release

Abstract Comprehensive characterization of kaolin sand from the Vyšný Petrovec (VP) deposit in Slovakia by a variety of experimental methods was performed. The quantitative XRD analysis (RockJock software) revealed that the acid-untreated sample contained mainly kaolinite (~60 wt. %), a considerable amount of dioctahedral micas (~32 wt. %) and quartz (~ 7 wt. %). The Hinckley index (HI) and Aparicio-Galán-Ferrel index (AGFI) calculated from the 02l and 11l reflections showed medium-defect kaolinite to be present in the VP kaolin. The influence of the mineral composition of VP kaolin on its stability in 6 mol · dm-3 HCl at 95 °C was investigated. The solid reaction products were examined by chemical analysis; XRD and infrared spectroscopy in both middle (MIR) and near (NIR) regions. Considerably higher dissolution rate of Fe compared to Al indicated that Fe was bounded in a readily soluble phase rather than in kaolinite. While the MIR spectra confirmed the gradual release of the central atoms from the clay minerals layers and creation of amorphous silica upon acid treatment, the NIR spectra revealed the formation of Si-OH groups in the solid reaction product. Relatively high dissolution rate of VP kaolin resulted from the presence of small-grains of mediumdefect kaolinite and clay admixtures in VP kaolin sand.

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INVESTIGATION OF LIQUID-PHASE OXIDATION OF NAPHTHENE-PARAFFINIC HYDROCARBONS OF BALAKHANY OIL

JOURNAL OF ADVANCES IN CHEMISTRY ◽

10.24297/jac.v11i5.4472 ◽

2015 ◽

Vol 11 (5) ◽

pp. 3540-3546 ◽

Cited By ~ 2

Author(s):

V.M. Abbasov ◽

L.M. Afandiyeva ◽

L.I. Aliyeva ◽

L.H. Nuriyev ◽

Ch.Q. Salmanova ◽

...

Keyword(s):

Liquid Phase ◽

Ir Spectroscopy ◽

Catalytic Oxidation ◽

Optical Density ◽

Oxidation Reaction ◽

Oxidation Process ◽

Aerobic Oxidation ◽

Hydroxyl Groups ◽

Phase Oxidation ◽

Mechanism Of Oxidation

Liquid-phase aerobic oxidation of naphthene-paraffinic hydrocarbons at 217-330о С of diesel fraction of Balakhany oils in the presence of the mixtures of Mn, Cr salts of natural petroleum acids (MeNPA) has been investigated. The catalytic oxidation process is realized for 7 hours at temperature 135-1400C in a barbotage reactor. Samples were taken every hour and oxidized product was separated by composition in accordance with known methods. Mechanism of oxidation process of naphthene-paraffinic hydrocarbons has been studied by IR- spectroscopy. It has been found that, after 5 hours oxidation of naphthene-paraffinic hydrocarbons the yield of obtaining synthetic petroleum acids rich 16,5%, the yield of oxysynthetic petroleum acids-18%. The changes of the optical density of a carbonyl and a hydroxyl groups depending on the time were studied. It was found that the oxidation reaction should be conducted within 6 hours, as D1713(C=O) and D941(OH) after 6 hours decrease and it’s probably connected with beginning decomposition process of the acids and oxyacids.

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SOME ISSUES OF THE MECHANISM OF DEEP OXIDATION OF ETHANOL ON THE SURFACE OF THE CATALYST OF A THERMOCATALYTIC SENSOR

EurasianUnionScientists ◽

10.31618/esu.2413-9335.2021.1.87.1392 ◽

2021 ◽

pp. 27-32

Author(s):

Z. Murodova ◽

M. Hushvaktov ◽

Z. Abdurahmanova

Keyword(s):

Catalytic Oxidation ◽

Catalyst Surface ◽

Deep Oxidation ◽

Optimal Conditions ◽

Reaction Products ◽

Heterogeneous Catalytic ◽

Partial Pressures ◽

Kinetic Region ◽

Oxidation Of Ethanol

In this work, the effect of the partial pressures of the starting materials and reaction products on the patterns of deep oxidation of ethanol on the surface of the catalyst of the thermocatalytic sensor was studied experimentally. At the same time, the regularities of the oxidation of combustible substances on selected catalysts have been established and the optimal conditions have been identified that ensure the flow of the process under study in the kinetic region. It is shown that the reaction on the sensor catalyst surface proceeds along two kinetically independent (basic) routes. Taking into account the above, a more detailed scheme of the heterogeneous catalytic oxidation of ethanol in the presence of a sensor catalyst is proposed.

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