A soil susceptible to heat‐induced water repellency was heated at several temperatures and oxygen concentrations. The materials emanating from the heated soil were captured and their mass determined. The greatest quantity of products was captured at temperatures above 300C. Increasing amounts of material were produced with increasing oxygen concentrations up to 20%. From 0.3% to 1.75% of the total soil was captured as products.Fractionation of these captured products by adsorption chromatography resulted in the isolation of several different components. Three of these components were capable of causing extreme water repellency in sand if the treated sand were heated. Some evidence suggested that the heating of these substances on the sand surfaces altered their structure. These three effective components represented from 25–50% of the total materials collected from the soil.Elemental and spectroscopic analyses of the effective components indicated them to be basically aliphatic hydrocarbons.The undecomposed and partially decomposed plant materials present in the soil were determined to be the primary source of the products coming from the heated soils.
Fugitive emissions from a slagging fixed-bed coal-gasification pilot plant were analyzed by flameless atomic absorption spectrophotometry, gas chromatography, and mass spectrometry for trace metal and trace organic species. Analysis of the size distributions of airborne particulate matter inside the plant showed an abundance of large metal-containing particles; outdoor distributions in the vicinity of the plant resembled the indoor distributions, suggesting the importance of the gasifier in influencing ambient air quality. This conclusion was further supported by identification of similar organic compounds inside and outside the plant. Trace element enrichment factors based on the earth's crustal composition were greater than those based on the composition of the lignite used in the gasifier, showing the importance of characterizing the proper source material when inverstigating chemical fraction during aerosol formation. Enrichments in the present study were much greater than those found in previous sampling during aborted start-up and cleaning procedures, where normal operating temperatures had not yet been reached. Both studies showed evidence of enrichment factors which decreased with increasing particle size. Although much of the airborne mass was associated with large particles having low respirability, the high concentrations of some metals indoors suggests that further assessment of potential occupational exposures is warranted.
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