Analysis of Oil-Shale Products Using a Multitechnique Approach

摘要

Inorganic analysis of solid, liquid, particulate, and gaseous samples from the Paraho Semiworks Retort was completed using a multi-technique approach. Most of the techniques used instrumental methods, so that interferences from chemically complex matrices could be minimized. In many cases, analytical techniques were altered or improved in order to make them applicable to oil shale samples. The techniques employed for most of the analyses were a combination of instrumental neutron activation, energy dispersive x-ray fluorescence, flame atomic absorption spectroscopy and dc plasma emission spectroscopy. Additional analyses were performed by graphite furnace atomic absorption, cold vapor atomic absorption, and radiochemical activation. The data were statistically analyzed to determine the precision of each method and to see how closely the various techniques compared. Better than 10% comparisons between two or more of the techniques were obtained for analyses of Al, Ba, Ca, Cu, Fe, K, Mg, Mn, Na, Rb, Si, U, V, and Zn. Better than 20% comparisons were obtained for Cd, Cr, Mo and Ti. Systematic differences of about 15 to 20% between x-ray fluorescence and neutron activation determinations of arsenic were noted, with the neutron activation being generally higher. The environmentally interesting elements B, Hg, and Se could be reliably determined by only one method, so intercomparisons could not be made. Fluorine could not be reliably determined by any technique (selective ion electrode, colorimetry) that we tried. The data were also used to construct mass balances for 31 trace and major elements in the various effluents, including the offgas for the Paraho retort operating in the direct mode.