This practice describes a high-pressure, high-temperature digestion technique using the high-pressure asher (HPA) for preparation of oils and oily waste specimens for determination of up to 28 different elements by inductively coupled plasma-atomic emission plasma spectroscopy (ICP-AES), cold-vapor atomic absorption spectroscopy (CVAAS), and graphite furnace atomic absorption spectroscopy (GFAAS), inductively coupled plasma-mass spectrometry (ICPMS), and radiochemical methods.

Formerly under the jurisdiction of Committee C26 on Nuclear Fuel Cycle, this test method was withdrawn in July 2009. This standard is being withdrawn without replacement because significant safety issues were identified in an early review which have not been completely resolved.

This practice is useful for preparation of difficult-to-digest, primarily oils and oily wastes, specimens for trace element determinations of up to 28 elements by atomic absorption or plasma emission techniques. Specimen preparation by high-pressure ashing is primarily applicable to specimens whose preparation by EPA SW-846 protocols is either not applicable or not defined. This sample preparation practice is applicable for the trace element characterization of mixed oily wastes for use by waste treatment facilities such as incinerators or waste stabilization facilities.

1.1 This test method describes a high-pressure, high-temperature digestion technique using the high-pressure asher (HPA) for preparation of oils and oily waste specimens for determination of up to 28 different elements by inductively coupled plasma-atomic emission plasma spectroscopy (ICP-AES), cold-vapor atomic absorption spectroscopy (CVAAS), and graphite furnace atomic absorption spectroscopy (GFAAS). Oily and high-percentage organic waste streams from nuclear and non-nuclear manufacturing processes can be successfully prepared for trace element determinations by ICP-AES, CVAAS, and GFAAS. This method is applicable to the determination of total trace elements in these mixed wastes. Specimens prepared by this method can be used to characterize organic mixed waste streams received by hazardous waste treatment incinerators and for total element characterization of the waste streams.

1.2 This test method is applicable only to organic waste streams that contain radioactivity levels that do not require special personnel or environmental protection from radioactivity or other acute hazards.

1.3 A list of elements determined in oily waste streams is found in Table 1.

1.4 This test method has been used successfully to completely digest a large variety of oils and oily mixed waste streams from nuclear processing facilities. While the method has been used to report data on up to 28 trace elements, its success should not be expected for all analytes in every specimen. The overall nature of these oily wastes tends to be heterogeneous that can affect the results. Homogeneity of the prepared sample is critical to the precision and quality of the results. Some elements, notably silver and antimony, may be recovered on a semiquantitative basis, while most results are highly quantitative.

1.5 This procedure is designed to be applicable to samples whose preparation methods are not defined, or not suitable, by other regulatory procedures or requirements, such as the U.S. Environmental Protection Agency (EPA) SW-846 and EPA-600 4-79-020 documents. This digestion method is designed to provide a high level of accuracy and precision, but does not replace or override any regulatory requirements for sample preparation.

1.6 This method uses hazardous materials, operations, and equipment at high pressure (90-110 bars, 89-108 atm, or 1305-1595 lb/in.2) and high temperatures, up to 320°C, and therefore poses significant hazards if not operated properly. This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific hazard statements are given in Sections 10 and 11.