Exclusion chromatography with multiple detectors for following compositional changes of petroleum residuals during desulfurization

This review covers the time period of about December 1975 to November 1977. Since we depend on abstracting services in some cases, there is some time overlap with the period covered by the last review (73). The literature surveyed for this review included major analytical, chromatography, and polymer journals, as well as various abstracting services. We've included literature on size separation from soft gels ("gel filtration"), semi-rigid gels ("GPC"), and porous, inorganic column packings ("rigid gels"). And we've reviewed size separations involving small molecules as well as work restricted to macromolecules. We continue to use the common abbreviation, GPC, for gel permeation chromatography applications involving all the above areas. The more definitive "steric exclusion chromatography" is, however, still preferred nomenclature. GENERAL REVIEWSA number of books published during this period included one or more sections on theory and use of steric exclusion chromatography (28,55,152,174,176). Several review articles also included general GPC information. Abbott (1) and Miller (129) discussed elementary operating principles and usefullness for polymer analyses. Krauss and Krauss reviewed theory and practice of both thin layer and column GPC (105). Current status of aqueous GPC was reviewed by Cooper and

Section: Literature Servicesmentioning

confidence: 99%

Gel permeation chromatography (steric exclusion chromatography)

Gaylor¹,

James²

1978

“…The nonideal elution behavior, particularly noticeable for the pericondensed polynuclear aromatics, has been observed in tetrahydrofuran (8), toluene 0003-2700/80/0352-1877801.00/0 (9), benzene (9, 10), and methylene chloride (4, 5). This behavior, sometimes attributed to adsorption (10), generally results in a nonlinear calibration curve at low molecular weights for petroleum residuals (12,13) and polymeric pitches (14). Bergmann et al (9) have reported that the anomalous elution behavior of pitch molecules disappears when 1,2,4trichlorobenzene is used as the gel permeation chromatographic (GPC) solvent.…”

mentioning

confidence: 99%

Determination of molecular weight distributions of polymerized petroleum pitch by gel permeation chromatography with quinoline eluent

Greinke¹,

O'Connor²

1980

A significant advantage peculiar to this industry is that practically all of the radiologically "hot" sample components are separated from the solution that is actually injected into the ion chromatograph. This means that the instrument does not become contaminated with radionuclides to the extent that it would with direct sample injection. This significantly reduces personnel exposure to radiation and in practice saves the trouble and expense of trying to clean up or replace (and correctly dispose of) the "hot" columns.

Analytical and Process Instrumentation

Loveland¹,

White²

1979

or of alkyl phenyl phosphite, respectively. Methods applicable to phosphorus and nitrogen [Kolb et al. (94K) and ] and two methods applicable to phosphorus and sulfur [Patterson (136K) and Patterson and Howe (137K)] are described in the sulfur and nitrogen portions of this review.The determination of arsenic in catalytic reformer feedstocks by flameless atomic adsorption published by La Villa and Queraud (103K) involves adding 5 mL of 1% iodine in toluene, extracting twice with 10 mL of 1% nitric acid, evaporating the extract to dryness, adding 2 mL of 1% nitric acid, running the sample in the spectrometer, and comparing the results with those for a blank and for standard solutions of arsenic and magnesium. Michelot (114K) determined silicon in coking naphthas contaminated with siloxane antifoam agents by using a direct reading emission spectrometer equipped with a graphite rotating-disk electrode; the naphtha is diluted with mineral oil sufficient to reduce the combustion rate but not to affect the sensitivity.