ASTM D6376 Standard Test Method for Determination of Trace Metals in Petroleum Coke by Wavelength Dispersive X-ray Fluorescence Spectroscopy
1. Scope
1.1 This test method covers the X-ray fluorescence spectrometric determination of total sulfur and trace metals in samples of raw or calcined petroleum coke. Elements determined using this test method are listed in Table 1.
1.2 Detection limits, sensitivity, and optimal element ranges will vary with matrices, spectrometer type, analyzing crystal, and other instrument conditions and parameters.
1.3 All analytes are determined as the element and reported as such. These include all elements listed in Table 1. This test method may be applicable to additional elements or concentration ranges if sufficient standards are available to produce proper calibration equations.
1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.5 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.
2. Referenced Documents
2.1 ASTM Standards:
D346 Practice for Collection and Preparation of Coke Samples for Laboratory Analysis
D1552 Test Method for Sulfur in Petroleum Products by High Temperature Combustion and Infrared (IR) Detection or Thermal Conductivity Detection (TCD)
D4057 Practice for Manual Sampling of Petroleum and Petroleum Products
D5056 Test Method for Trace Metals in Petroleum Coke by Atomic Absorption
D5600 Test Method for Trace Metals in Petroleum Coke by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES)
D6969 Practice for Preparation of Calcined Petroleum Coke Samples for Analysis
D6970 Practice for Collection of Calcined Petroleum Coke Samples for Analysis
E11 Specification for Woven Wire Test Sieve Cloth and Test Sieves
3. Terminology
3.1 Definitions:
3.1.1 calcined petroleum coke, n - petroleum coke that has been thermally treated to drive off the volatile matter and to develop crystalline structure.
3.1.2 green petroleum coke, n - same as raw petroleum coke.
3.1.3 petroleum coke, n - a solid, carbonaceous residue produced by thermal decomposition of heavy petroleum fractions or cracked stocks, or both.
3.1.4 raw petroleum coke, n - petroleum coke that has not been calcined.
3.2 Definitions ofTerms Specific to This Standard:
3.2.1 alpha, n - correction factor used to compensate for interferences.
3.2.2 analytical sample, n - a representative fraction taken from a larger mass of petroleum coke and reduced by grinding to pass a 75 µm (U.S. No. 200 mesh) sieve.
3.2.3 pellet, n - a blend of dried sample and binder milled together and then formed into a pellet by pressure.
3.2.4 reference samples, n - samples of known concentrations to be used in the calibration of the X-ray fluorescence spectrometer.
