Monitoring of the Chemical Species in a Liquid-Phase Claus Reaction

2009 ◽  
Vol 23 (9) ◽  
pp. 4404-4412 ◽  
Author(s):  
Charlotte Rouquette ◽  
Mathieu Digne ◽  
Laurent Renaudot ◽  
Julien Grandjean ◽  
Jean-Pierre Ballaguet
Keyword(s):  
Liquid Phase ◽  
Chemical Species ◽  
Claus Reaction

through tubing and fittings made of PTFE. Analysis was undertaken by the Warren Spring Laboratory of the Department of Trade and Industry, according to the method described by Bailey and Bedbo rough The results are shown in Table IV. and plotted in Fig. 3. and 4. Table IV. Variation of odour strength of extracted samples with volune of eluted air Volume of air Strength of odour samples passing through (dilutions) sludge before sampling (1/1) Raw sludge Digested sludge 0 154 000 9 900 11.1 53 000 350 22.2 30 600 270 55.6 15 500 190 111 8 200 160 It is clear from these results that there is considerable die-off of odour strength with time, and that, as would be expected, the anaerobic digestion of sludge can reduce the odour potential by at least one order of magnitude. To illustrate the importance of this die-off effect, the results have been re-plotted in Fig. 5. in a cunulative form; that is to say as cumulative percentage of the eventual colour release against volume of air. In the case of the raw sewage sludge, 38% of the ultimate odour was carried in the first odour sample, and 90% of the odour had been extracted by the passage of about 200 1. In the case of the anaerobically digested sludge, the same effect is much more marked; 72% of the ultimate odour was carried by the first sample, and thereafter the strength of the odour fell off very rapidly. There are two possible explanations for this. First, it can be postulated that as it is known that many of the important odorous chemical species are highly volatile, they may be only physically trapped in the sludge, and need little encouragement to transfer to the atmosphere. An alternative explanation concerns the existence of two equilibria. As the vapour/liquid equilibrium is disturbed by the passage of air, the concentration of dissolved compounds in the liquid phase falls, disturbing the ’solid’/liquid equilibrium The kinetics of transfer across this latter phase boundary are much slower than for the liquid/vapour transfer, so that the extraction of odour becomes limited by the rate of diffusion into the liquid phase. Two observations may be cited as evidence for this latter view. First, when sludge is applied to land, there is a rapid tail-off of odour nuisance after spreading. Hie incidence of rain after a dry period is known to result in an increased evolution of odour. Second, in earlier experiments samples of sludge were centrifuged, and the supernatant liquor discarded and replaced by tap water, before being used in the standard odour potential test. Some re-extraction of odour from the samples was rapidly found. In practice, both postulated mechanisms are probably at work, especially if the concept of ’solid/liquid equilibrium’ be extended to

1986 ◽  
pp. 152-152
Keyword(s):  
Liquid Phase ◽  
Tap Water ◽  
Chemical Species ◽  
Liquid Equilibrium ◽  
Digested Sludge ◽  
Order Of Magnitude ◽  
Anaerobically Digested Sludge ◽  
Solid Liquid ◽  
Kinetics Of ◽  
Potential Test

Efficient Regeneration of SO2-Absorbed Functional Ionic Liquids with H2S via the Liquid-Phase Claus Reaction

2019 ◽  
Vol 7 (12) ◽  
pp. 10931-10936 ◽  
Author(s):  
Qi Zhang ◽  
Yucui Hou ◽  
Shuhang Ren ◽  
Kai Zhang ◽  
Weize Wu
Keyword(s):  
Ionic Liquids ◽  
Liquid Phase ◽  
Claus Reaction ◽  
Efficient Regeneration

scholarly journals Contribution of gaseous and particulate species to droplet solute composition at the Puy de Dôme, France

2003 ◽  
Vol 3 (5) ◽  
pp. 1509-1522 ◽  
Author(s):  
K. Sellegri ◽  
P. Laj ◽  
A. Marinoni ◽  
R. Dupuy ◽  
M. Legrand ◽  
...  
Keyword(s):  
Liquid Phase ◽  
Gas Phase ◽  
Removal Rate ◽  
Chemical Species ◽  
Solute Concentration ◽  
Complex Nature ◽  
Gaseous Species ◽  
Phase Partitioning ◽  
Gas Phases ◽  
Set Up

Abstract. Chemical reactions of dissolved gases in the liquid phase play a key role in atmospheric processes both in the formation of secondary atmospheric compounds and their wet removal rate but also in the regulation of the oxidizing capacity of the troposphere. The behavior of gaseous species and their chemical transformation in clouds are difficult to observe experimentally given the complex nature of clouds. During a winter field campaign at the summit of the Puy de Dôme (central France, 1465 m a.s.l), we have deployed an experimental set-up to provide a quantification of phase partitioning of both organic (CH3COOH, HCOOH, H2C2O4) and inorganic (NH3, HNO3, SO2, HCl) species in clouds. We found that nitric and hydrochloric acids can be considered close to Henry's law equilibrium, within analytical uncertainty and instrumental errors. On another hand, for NH3 and carboxylic acids, dissolution of material from the gas phase is kinetically limited and never reaches the equilibrium predicted by thermodynamics, resulting in significant sub-saturation of the liquid phase. On the contrary, SIV is supersaturated in the liquid phase, in addition to the presence of significant aerosol-derived SVI transferred through nucleation scavenging. Upon droplet evaporation, a significant part of most species, including SIV, tends to efficiently return back into the gas phase. Overall, gas contribution to the droplet solute concentration ranges from at least 48.5 to 98% depending on the chemical species. This is particularly important considering that aerosol scavenging efficiencies are often calculated assuming a negligible gas-phase contribution to the solute concentration. Our study emphasizes the need to account for the in-cloud interaction between particles and gases to provide an adequate modeling of multiphase chemistry systems and its impact on the atmospheric aerosol and gas phases.

A three-dimensional numerical simulation of sulfate transport and redistribution

2003 ◽  
Vol 81 (9) ◽  
pp. 1067-1094 ◽  
Author(s):  
V Spiridonov ◽  
M Curic
Keyword(s):  
Liquid Phase ◽  
Wet Deposition ◽  
Cloud Model ◽  
Chemical Species ◽  
Liquid Phase Oxidation ◽  
Atmospheric Pollutants ◽  
Total Sulfur ◽  
Cloud Chemistry ◽  
Phase Oxidation ◽  
The Impact

We have utilized a relatively sophisticated dynamic cloud model combined with standard bulk-parameterized microphysics and simple sulfur chemistry to explore the impact of deep convection on modification and transport of a suite of pollutants. Two base run simulation parameters are used to initialize the cloud-chemistry model. The simulation of the 6 July 1995 case, with continental polluted field initialization, has revealed that a convective storm generates strong vertical transport of gases and particulate compounds from the planetary boundary layer (PBL) to the upper troposphere (UT), perturbation of aerosol physical and chemical properties, modification of pollutant concentration, and change of the spatial distributions of chemical species. The early formation of precipitation and enhanced scavenging contributed to a registration of approximately 2.5 times the concentration of sulfate in the precipitation near the surface than in the air found at this level. The Spring case numerical experiment on 3 April 2000 with a chemical background taken from Macedonia, provided insight into the potential influence of the long-range transport of atmospheric pollutants and ascertained quantitative–qualitative information about processes by which acidic species are incorporated into precipitation. The model-computed parameters are in good agreement with observation. The average equivalent cloud water pH and rainwater pH when the higher acid precipitation occurs are about 5.0 and 4.5, respectively. The results from a number of sensitivity tests of cloud chemistry of the physical processes for the continental nonpolluted and continental polluted environments, indicate that nucleation and impact scavenging of aerosols account for between 20%–24% of the total sulfur mass removed by wet deposition. Liquid-phase oxidation contributes about 20%–28% of the sulfur content in precipitation. It means that neglecting liquid-phase oxidation when considering the chemistry in these clouds may lead to underestimates of about 20%–28% in sulfate wet deposition. Neglect of the ice phase when considering the chemistry in continental nonpolluted and continental polluted clouds may lead to overestimates of about 112%–130% of the total sulfur mass removed by wet deposition. The assumption of Henry's law equilibrium for those types of clouds gives an overestimation of about 100%–120%, respectively. PACS Nos.: 51.10.+y, 92.60.Sz

Samsonov’s Model for Electronic Mechanism of Sintering and its Relevance

2009 ◽  
Vol 624 ◽  
pp. 57-69
Author(s):  
Gopal S. Upadhyaya
Keyword(s):  
Liquid Phase ◽  
Chemical Species ◽  
Electronic Configuration ◽  
Liquid Phase Sintering ◽  
Alloy Design ◽  
Present Review ◽  
Configuration Model ◽  
Electronic Nature ◽  
Electronic Mechanism ◽  
Stable Electronic Configuration

In the present review a generalized view of sintering mechanism on the basis of the electronic nature of the chemical species involved has been highlighted. The stable electronic configuration model proposed by G.V.Samsonov is one of the models. In spite of the fact that the model is qualitative, its far reaching impact in explaining liquid phase sintering and activated sintering of real systems can not be minimized. In a way the model holds a premium in its predictive nature , which is so crucial not only in sintering processing, but also in alloy design based on metallic or ceramic systems or composites constituted out of these.

Treatment of industrial gases to remove sulfur dioxide by means of liquid-phase claus reaction

1979 ◽  
Vol 15 (3) ◽  
pp. 198-200 ◽  
Author(s):  
A. V. Gladkii ◽  
M. V. Stepanova ◽  
T. V. Onopko ◽  
N. K. Shchekina
Keyword(s):  
Liquid Phase ◽  
Sulfur Dioxide ◽  
Claus Reaction ◽  
Industrial Gases ◽  
Remove Sulfur Dioxide

Chemical Species Identification in an SEM by Changes in Emitted X-Ray Energies

1974 ◽  
Vol 32 ◽  
pp. 570-571
Author(s):  
R. H. Duff
Keyword(s):  
Species Identification ◽  
Valence Electron ◽  
Chemical Species ◽  
X Rays ◽  
Chemical Bonds ◽  
Small Shift ◽  
X Ray ◽  
Electron Transitions ◽  
Peak Energy ◽  
Chemical Combination

A material irradiated with electrons emits x-rays having energies characteristic of the elements present. Chemical combination between elements results in a small shift of the peak energies of these characteristic x-rays because chemical bonds between different elements have different energies. The energy differences of the characteristic x-rays resulting from valence electron transitions can be used to identify the chemical species present and to obtain information about the chemical bond itself. Although these peak-energy shifts have been well known for a number of years, their use for chemical-species identification in small volumes of material was not realized until the development of the electron microprobe.

Elucidation of block boundaries as the dissolution channels in hydrated cement

1978 ◽  
Vol 36 (1) ◽  
pp. 484-485
Author(s):  
N.V. Belov ◽  
U.I. Papiashwili ◽  
B.E. Yudovich
Keyword(s):  
Liquid Phase ◽  
Grain Boundaries ◽  
Benzoyl Peroxide ◽  
Phase Contrast ◽  
Active Role ◽  
Point Of View ◽  
Hardened Cement ◽  
Hydrated Cement ◽  
Hardened Cement Paste

It has been almost universally adopted that dissolution of solids proceeds with development of uniform, continuous frontiers of reaction.However this point of view is doubtful / 1 /. E.g. we have proved the active role of the block (grain) boundaries in the main phases of cement, these boundaries being the areas of hydrate phases' nucleation / 2 /. It has brought to the supposition that the dissolution frontier of cement particles in water is discrete. It seems also probable that the dissolution proceeds through the channels, which serve both for the liquid phase movement and for the drainage of the incongruant solution products. These channels can be appeared along the block boundaries.In order to demonsrate it, we have offered the method of phase-contrast impregnation of the hardened cement paste with the solution of methyl metacrylahe and benzoyl peroxide. The viscosity of this solution is equal to that of water.

Identification of hepatitis a virus in cell cultures by solid phase immune electron microscopy

1986 ◽  
Vol 44 ◽  
pp. 238-239
Author(s):  
C.D. Humphrey ◽  
T.L. Cromeans ◽  
E.H. Cook ◽  
D.W. Bradley
Keyword(s):  
Electron Microscopy ◽  
Liquid Phase ◽  
Cell Cultures ◽  
Rapid Detection ◽  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Solid Phase ◽  
Immune Electron Microscopy ◽  
Detection And Identification

There is a variety of methods available for the rapid detection and identification of viruses by electron microscopy as described in several reviews. The predominant techniques are classified as direct electron microscopy (DEM), immune electron microscopy (IEM), liquid phase immune electron microscopy (LPIEM) and solid phase immune electron microscopy (SPIEM). Each technique has inherent strengths and weaknesses. However, in recent years, the most progress for identifying viruses has been realized by the utilization of SPIEM.

Confocal Raman mapping

1992 ◽  
Vol 50 (2) ◽  
pp. 1514-1515
Author(s):  
J. Barbillat ◽  
M. Delhaye ◽  
P. Dhamelincourt
Keyword(s):  
Chemical Species ◽  
Diffraction Limit ◽  
Microscopic Level ◽  
Raman Mapping ◽  
Complete Spectrum ◽  
Laser Illumination ◽  
Ccd Detector ◽  
Raman Microprobe ◽  
Photodiode Array ◽  
Raman Image

Raman mapping, with a spatial resolution close to the diffraction limit, can help to reveal the distribution of chemical species at the surface of an heterogeneous sample.As early as 1975,three methods of sample laser illumination and detector configuration have been proposed to perform Raman mapping at the microscopic level (Fig. 1),:- Point illumination:The basic design of the instrument is a classical Raman microprobe equipped with a PM tube or either a linear photodiode array or a two-dimensional CCD detector. A laser beam is focused on a very small area ,close to the diffraction limit.In order to explore the whole surface of the sample,the specimen is moved sequentially beneath the microscope by means of a motorized XY stage. For each point analyzed, a complete spectrum is obtained from which spectral information of interest is extracted for Raman image reconstruction.- Line illuminationA narrow laser line is focused onto the sample either by a cylindrical lens or by a scanning device and is optically conjugated with the entrance slit of the stigmatic spectrograph.

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