A pressure-affected headspace-gas chromatography method for determining calcium carbonate content in paper sample

- A pressure effect based headspace analysis technique.
- Based on measuring the oxygen signal change effected by the CO2 from converted from carbonate.
- The present method is suitable for determining high carbonate containing samples.

The present work reports on the development of a pressure-affected based headspace (HS) analytical technique for the determination of calcium carbonate content in paper samples. By the acidification, the carbonate in the sample was converted to CO2 and released into the headspace of a closed vial and then measured by gas chromatography (GC). When the amount of carbonate in the sample is significant, the pressure created by the CO2 affects the accuracy of the method. However, the pressure also causes a change in the O2 signal in the HS-GC measurement, which is a change that can be used as an indirect measure of the carbonate in the sample. The results show that the present method has a good precision (the relative standard deviation < 2.32%), and good accuracy (the relative differences compared to a reference method was < 5.76%). Coupled with the fact that the method is simple, rapid, and accurate, it is suitable for a variety of applications that call for the analysis of high carbonate content in paper samples.