Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Gas adsorption chromatography

Paper chromatography Ion exchange chromatography Electrophoresis Gas chromatography Adsorption chromatography Gel permeation chromatography... [Pg.333]

CH4 + CO2 2C0 + 2H2 and CH4 + H2O CO + 3H2 reaction were carried out 1n a tubular flow reactor made of pyrex glass at 773 K and normal pressure. The reactant gases were CH4/C02/N2(carrier gas)=l/l/2 and CH4/H20/N2=l/l/2 both in molar ratio. The products were analyzed by gas chromatography. Adsorption measurement... [Pg.68]

In the future it should prove worthwhile to pay more attention to the development of fields of gas adsorption capillary chromatography such as adsorption capillary columns in multidimensional gas chromatography, adsorption capilleuy columns with nonporous (or slightly porous) inner surfaces, theory of separation, optimization, application of modified... [Pg.310]

Gas chromatography Adsorption of a compound on a carrier material (gas phase)... [Pg.371]

The crystalline mineral silicates have been well characterized and their diversity of stmcture thoroughly presented (2). The stmctures of siHcate glasses and solutions can be investigated through potentiometric and dye adsorption studies, chemical derivatization and gas chromatography, and laser Raman, infrared (ftir), and Si Fourier transform nuclear magnetic resonance ( Si ft-nmr) spectroscopy. References 3—6 contain reviews of the general chemical and physical properties of siHcate materials. [Pg.3]

Several properties of the filler are important to the compounder (279). Properties that are frequentiy reported by fumed sihca manufacturers include the acidity of the filler, nitrogen adsorption, oil absorption, and particle size distribution (280,281). The adsorption techniques provide a measure of the surface area of the filler, whereas oil absorption is an indication of the stmcture of the filler (282). Measurement of the sdanol concentration is critical, and some techniques that are commonly used in the industry to estimate this parameter are the methyl red absorption and methanol wettabihty (273,274,277) tests. Other techniques include various spectroscopies, such as diffuse reflectance infrared spectroscopy (drift), inverse gas chromatography (igc), photoacoustic ir, nmr, Raman, and surface forces apparatus (277,283—290). [Pg.49]

Gas chromatography, depending on the stationary phase, can be either gas—Hquid chromatography (glc) or gas—soHd chromatography (gsc). The former is the most commonly used. Separation in a gas—Hquid chromatograph arises from differential partitioning of the sample s components between the stationary Hquid phase adsorbed on a porous soHd, and the gas phase. Separation in a gas—soHd chromatograph is the result of preferential adsorption on the soHd or exclusion of materials by size. [Pg.106]

SERS has also been applied as a sensitive, molecule-specific detection method in chromatography, e.g. thin layer, liquid, and gas chromatography. SERS-active colloids were deposited on the thin layer plates or mixed continuously with the liquid mobile phases. After adsorption of the analytes, characteristic spectra of the fractions were obtained and enabled unambiguous identification of very small amounts of substance. [Pg.263]

Lab method with high performance liquid chromatography after collection in an impinger containing water Charcoal adsorption tube and gas chromatography... [Pg.360]

Lab method using porous polymer adsorption tube and thermal desorption with gas chromatography Lab method using porous polymer diffusive samplers with thermal desorption and gas chromatography Lab method using pumped acid-coated filters, desorption and liquid chromatography... [Pg.360]

Chlorinated hydrocarbon solvent vapours in air Lab method using pumped charcoal adsorption tubes, solvent desorption and gas chromatography 28... [Pg.361]

Lab method using pumped porous polymer adsorption tubes, thermal desorption and gas chromatography 40... [Pg.363]

The adsorption of gas onto a solid surface can also be used to estimate surface energy. Both inverse gas chromatography (IGC) and isotherm measurement using the BET method [19] have been used. Further discussion and detailed references are given by Lucic et al. [20] who compare the application of IGC, BET and contact angle methods for characterising the surface energies of stearate-coated calcium carbonate fillers. [Pg.323]

Charcoal Tubes Reference has been made earlier to adsorption, which is the property of some solid materials, such as activated charcoal, to physically retain solvent vapors on their surfaces. In environmental health testing, the adsorbed vapors are removed, generally with a solvent, in a laboratory. The solvent is then analyzed by physical methods (gas chromatography, etc.) to determine the individual compounds whose vapors, such as benzene, were present in the sampled air. Industrial atmospheric samples can be collected in small glass tubes (4 mm ID) packed with two sections of activated charcoal, separated and retained with fiberglass plugs. To obtain an air sample, the sealed ends of the tube are broken off, and air is drawn through the charcoal at the rate of 1 liter per minute by means... [Pg.276]

The great leap forward for chromatography was the seminal work of Martin and Synge (7) who in 1941 replaced countercurrent liquid-liquid extraction by partition chromatography for the analysis of amino acids from wool. Martin also realized that the mobile phase could be a gas rather than a liquid, and with James first developed (8) gas chromatography (GC) in 1951, following the gas-phase adsorption-chromatographic separations of Phillips (9). [Pg.3]

MDHS 1 Acrylonitrile in air Laboratory method using charcoal adsorption tubes and gas chromatography MDHS 2 Acrylonitrile in air Laboratory method using porous polymer adsorption tubes, and thermal desorption with gas chromatographic analysis... [Pg.239]

In gas chromatography samples are separated by distribution Ssetween a statloneu y phase and a mobile phase by adsorption,... [Pg.58]

In gas chromatography the value of the partition coefficient d ends only on the type of stationary phase and the column temperature. It is independent of column type and instrumental parameters. The proportionality factor in equation (l.ll) is called the phase ratio and is equal to the ratio of the volume of the gas (Vg) and liquid (V ) phases in the column. For gas-solid (adsorption) chromatography the phase ratio is given by the volume of the gas phase divided by the surface area of the stationary phase. [Pg.528]

T. Paryjczak, "Gas Chromatography in Adsorption and Catalysis", Wiley, Chichester, 1986. [Pg.635]

See other pages where Gas adsorption chromatography is mentioned: [Pg.112]    [Pg.421]    [Pg.1009]    [Pg.10]    [Pg.112]    [Pg.421]    [Pg.1009]    [Pg.10]    [Pg.97]    [Pg.142]    [Pg.740]    [Pg.35]    [Pg.13]    [Pg.346]    [Pg.476]    [Pg.1032]    [Pg.527]    [Pg.545]    [Pg.584]    [Pg.627]    [Pg.640]    [Pg.958]    [Pg.235]    [Pg.297]    [Pg.328]    [Pg.551]   
See also in sourсe #XX -- [ Pg.233 , Pg.234 ]

See also in sourсe #XX -- [ Pg.574 ]



SEARCH



Adsorption chromatography

Gas adsorption

© 2024 chempedia.info