ASTM D 7876:2013

1.1 This practice covers the procedure for use of microwave radiation for sample decomposition prior to elemental determination by atomic spectroscopy. 1.1.1 Although this practice is based on the use of inductively coupled plasma atomic emission spectrometry (ICP-AES) and atomic absorption spectrometry (AAS) as the primary measurement techniques, other atomic spectrometric techniques may be used if lower detection limits are required and the analytical performance criteria are achieved. 1.2 This practice is applicable to both petroleum products and lubricants such as greases, additives, lubricating oils, gasolines, and diesels. 1.3 Although not a part of Committee D02's jurisdiction, this practice is also applicable to other fossil fuel products such as coal, fly ash, coal ash, coke, and oil shale. 1.3.1 Some examples of actual use of microwave heating for elemental analysis of fossil fuel products and other materials are given in Table 1 . TABLE 1 Referenced Examples of Microwave Heating for Dissolution of Fossil Fuel and other Samples Material Element(s) Determined Measurement Technique Reference A Biological Materials Multiple AAS and NAA Abu Samra et al ( 1 ) Biological Materials Multiple AAS and NAA Barrett et al ( 2 ) West et al ( 3 ) Geological Materials Multiple Matthes et al ( 4 ) Oil Shales Multiple ICP-AES Nadkarni ( 5 ) Coal and Fly Ash Multiple ICP-AES Nadkarni ( 5 ) Plant and Grain Standards Multiple ICP-MS Feng et al ( 6 ) Greases Multiple ICP-AES Fox ( 7 ) ; Nadkarni ( 8 ) Petroleum Products Multiple ICP-AES Hwang et al ( 9 ) Crude Oil Multiple ICP-MS Xie et al ( 10 ) Residual Fuel Oil Multiple ICP-MS Wondimu et al ( 11 ) Oils Lanthanides and Platinum Group Metals ICP-MS Woodland et al ( 12 ) AAS; ICP-AES Kingston and Jassie ( 13 ) AAS; ICP-AES Kingston and Haswell ( 14 ) Soils and Sediments Lanthanides ICP-MS Ivanova et al ( 15 ) A The boldface numbers in parentheses refer to the list of references at the end of this standard. 1.3.2 Some additional examples of ASTM methods for microwave assisted analysis in the non-fossil fuels area are included in Appendix X1 . 1.4 During the sample dissolution, the samples may be decomposed with a variety of acid mixture(s). It is beyond the scope of this practice to specify appropriate acid mixtures for all possible combinations of elements present in all types of samples. But if the dissolution results in any visible insoluble material, this practice may not be applicable for the type of sample being analyzed, assuming the insoluble material contains some of the analytes of interest. 1.5 It is possible that this microwave-assisted decomposition procedure may lead to a loss of "volatile" elements such as arsenic, boron, chromium, mercury, antimony, selenium, and/or tin from the samples. Chemical species of the elements is also a concern in such dissolutions since some species may not be digested and have a different sample introduction efficiency. 1.6 A reference material or suitable NIST Standard Reference Material should be used to confirm the recovery of analytes. If these are not available, the sample should be spiked with a known concentration of analyte prior to microwave digestion. 1.7 Additional information on sample preparation procedures for elemental analysis of petroleum products and lubricants can be found in Practice D7455 . 1.8 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.9 This standard does not purport to address all of the safety concerns, 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 warning statements are given in Sections 6 and 7 .

75.080, 75.100