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The adsorptive capacities of activated carbon for major organic constituents (target compoun8s) of a wide variety of wastewater were measured in pure water and in actual ioastewater samples. Competitive adsorption due to the presence of other organic compoolentg of total organic carbon of the wastewater (background TOC) reduced carbon capacities for aU target compounds in the wastewaters from the respective pure water isotherms. The capacity reduction for a target compound was found to depend on the relative adsorptivity of the target compound versus competing compounds (poorly adsorbed TOC components produced a small reduction in capacity for a more strongly adsorbed target compound), and the fraction of the background TOC attributable to the target compound.Those findings were validded by carbon column adsorption breakthrough duta.

different silica materials were tested with approximately the same results. At this point, we prefer totally porous spherical packings. Superficially-porous materials can also be drawn into the microcapillaries, but the overall capacity of such columns is very

SummaryGas chromatrography (GC) with sulfur chemiluminescence detection (SCD) is an outstanding combination for selectively determining trace concentrations of sulfur compounds in hydrocarbon samples. GC peaks can be identified by retention times when reproducible, automated injection techniques are used. However, as described in this work, analysts should be on the look out for retention shifting due to solvent effects from sample components. Three examples of retention shifting are presented: (1) thiophene by benzene; (2) methylthiophenes by toluene; and (3) dibenzothiophene by gas oil. Depending on samples and analysis conditions, retention shifts from a few hundredths to 1.5 min have been observed. Such retention shifts are likely to cause errors in peak identifications. Therefore, when using SCD, simultaneous FID monitoring is recommended as an aid in evaluating chromatograms for possible retention shifting due to solvent effects.

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