Spectrochemical Determination of Boron in Carbon and Graphite

Abstract

Moving plate studies showed that the available material which best matched the volatility behavior of boron in carbon and graphite in the direct current arc was finely powdered iridium. When the discharge was burned in a 76 to 24 (by volume) argon-oxygen mixture, the line pair B 2497/Ir 2543 gave intensity ratios having a relative standard deviation of 1.870 or less between 0.5 and 4 p.p.m. boron. By use of a powder spark method, the sensitivity was extended to 0.25 p.p.m. boron. In this technique, a "sifter" electrode (a porous cup electrode with a perforated floor) was filled with powdered sample and used as the upper electrode in a high voltage spark discharge. The opening at the top of the electrode was closed with a small cork. During the discharge, the sample material sifted into the discharge area and was excited. When this discharge was conducted in argon, the line pair B 2497ICu 2492 gave a relative standard deviation of 1.870 or less between 0.25 and 7 p.p.m. boron.

AMS measurements of trace levels of boron in graphite

“…All this time the discovery of boron impurities in graphite represented an important goal, therefore many methods analyzing the boron content were developed and applied. [1][2][3][4][5][6] The current interest in determining trace levels of boron in graphite is determined by the need for graphite classication coming from the decommissioned nuclear power plants and from non-proliferation of nuclear high grade graphite. The best detection limit reached to date is in the range of tens of ng g À1 .…”

Determination of trace levels of boron in graphite powder by inductively coupled plasma-optical emission spectrometry (ICP-OES)

“…Non-destructive techniques such as energy dispersive X-ray uorescence (EDXRF) 5 and spectrochemical methods 6,7 have been employed for the determination of trace impurities in graphite powder. Boron could not be measured in EDXRF due to its low atomic number.…”

Development of Oxidative Pyrolysis Method for the Rapid Determination of Boron in Graphite Powders by Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES)

“…Due to this, the direct solid analysis-based techniques, such as laser ablation ICP-MS, electrothermal (ETV)-ICP-MS, instrumental neutron activation analysis (INAA), wavelength dispersive X-ray fluorescence spectrometry (WDXRF), and total reflection XRF, have been reported for the determination of trace impurities in graphite excluding boron (1,2,(13)(14)(15)(16). Emission spectrographic-based methods have been developed for the determination of boron in graphite (17)(18)(19). Xin-Li et al developed a slurry nebulization ICP-MS method for the direct determination of ultra-trace levels of boron in nuclear-grade graphite.…”