Adsorption chromatographic fractions

Adsorption Chromatographic Fractions. Examination of the data of Table V shows a tendency for distillates of lower-rank-coal liquids to contain more saturate material and less polyaromatic-... 

In the absence of adsorption, inclusion, or exclusion, a polymer is fractionated on a GPC column according to the hydrodynamic volume.40138 The hydrodynamic volume is a function of monomer identity, as well as polymer molecular weight, branching, and cross-linking. The polymer chains in any given chromatographic fraction have roughly the same hydrodynamic volume. 

Sulfur compounds in the gas oil fractions from two bitumens (Athabasca oil sand and Cold Lake deposit)> a heavy oil (Lloydminster) from Cretaceous reservoirs along the western Canada sedimentary basin, and a Cretaceous oil from a deep reservoir that may be mature (Medicine River) are investigated. The gas oil distillates were separated to concentrates of different hydrocarbon types on a liquid adsorption chromatographic column. The aromatic hydrocarbon types with their associated sulfur compounds were resolved by gas chromatographic simulated distillation and then by gas solid chromatography. Some sulfur compounds were further characterized by mass spectrometry. The predominant sulfur compounds in these fractions are alkyl-substituted benzo- and dibenzothiophenes with short side chains which have few dominant isomers. 

Because of adsorption effects, it is not recommended that surfactant mixtures be used. These mixtures tend to be chromatographically fractionated as the solution passes through the reservoir. The justification for the use of... 

A chromatographic fractionation procedure that uses a matrix consisting of a metal ion tightly bound to a matrix. Nickel is the most common metal ion used but there is use of copper and other transition metals. See Porath, J. and Ohn, B., Immobilized metal ion affinity adsorption and immobilized metal ion affinity chromatography of biomaterials. Serum protein affinities... 

Although the traditional method of separating the diastereomeric compounds generated in a resolution procedure is fractional crystallization, chromatographic procedures are now common and convenient. Diastereomeric compounds exhibit different adsorption... 

Chromatography of Nonsaponifiable Lipids. The nonsaponifiable residue plus 4.5 mg. of carrier cholesterol was applied to the top of a 7.5 X 1.7 cm. column containing 20 grams of Merck alumina (suitable for chromatographic adsorption) which had been previously deactivated by mixing with 7% aqueous acetic acid (10% glacial acetic acid in distilled water) (18). The column was packed in petroleum ether (redistilled, b.p. 60-70° C.) and 10 ml. fractions were collected. The eluting solvents are shown in Table II. 

Also, other dependent variables associated with CO2-foam mobility measurements, such as surfactant concentrations and C02 foam fractions have been investigated as well. The surfactants incorporated in this experiment were carefully chosen from the information obtained during the surfactant screening test which was developed in the laboratory. In addition to the mobility measurements, the dynamic adsorption experiment was performed with Baker dolomite. The amount of surfactant adsorbed per gram of rock and the chromatographic time delay factor were studied as a function of surfactant concentration at different flow rates. 

In the chromatographic liquid adsorptive separation process, the adsorption and desorption processes must occur simultaneously. After the desorption step, both the rejected product (product with lower selectivity, resulting in less adsorption by adsorbent) and the extracted product (product with higher selectivity, resulting in strong adsorption by adsorbent) contain desorbent In general, the desorbent is recovered by fractionation or evaporation and recycled back into the system. 

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