Analysis of graphite using current laboratory methods which involve the use of some form of filtration, may suffer from low recoveries. Graphite recovery, when employing the technique of filtration, is a function of the particle size distribution.
Accurate graphite analysis, as well as speciation of carbon forms can be directly performed using a single weighed sample without the use of acids and filtration. A 0.5 g sample is subjected to a multistage furnace treatment to analyze/remove species of carbon with the exception of graphitic carbon. Either a resistance or induction furnace can be used for analysis. During combustion, carbon-bearing elements are reduced; releasing the carbon, which immediately binds with the oxygen to form CO and CO , the majority being . Carbon is measured as carbon dioxide in the IR cell as gases flow through the IR cells. Carbon dioxide absorbs IR energy at a precise wavelength
within the IR spectrum.
All analysis is performed using Eltra instruments.
Eltra CW-800 CO2/Water Determinator – direct analysis only for , no other forms of carbon, using a resistance furnace.
Eltra CS-2000 – direct analysis for Total C, species dependent on sample pretreatment, using either an induction or resistance furnace.
Eltra Helios – direct analysis for Total C, species dependent on sample pretreatment, using a resistance furnace.
Method has been demonstrated to produce both accurate and precise analysis.