Standard GB/T3521-95 (4)

Fixed carbon determination method──indirect carbon determination method

5.1 Method summary

The indirect carbon determination method is also called the combustion method, that is, after the volatile and ash content of the sample are measured, they are subtracted from the total amount, and the difference is the fixed carbon content. This method is applicable to graphitized products with a carbon content of more than 50%.

5.2 Result calculation

5.2.1 The percentage of fixed carbon of high, medium and low carbon graphite is calculated according to formula (4):

x4=100%-x2-x3……………………(4)

In the formula: x4──Percentage of fixed carbon, %;

x2──Percent volatile content, %;

x3──The percentage of ash content, %.

5.2.2 The percentage of fixed carbon content of high-purity graphite is calculated according to formula (5):

x5=100%－x3……………………(5)

In the formula: x5──Percentage of fixed carbon, %;

x3──The percentage of ash content, %.