Chapter 5
5.7.2.3. Water content measurement K-F titration
A certain amount of sample was injected into the titration vessel with 25 ml
solvent. Water content was measured by Metrohm K-F 701 titrator. Detailed
procedure can be found in appendix C.
5.7.2.4. Titration calibration
In order to test the accuracy of K-F titration, emulsion samples of diluted
bitumen (after centrifugation, dilution ratio N/В is 0.7) with different known water
content were used for calibration. 30 ml emulsion samples were prepared by
mixing different amount of de-ionized water and diluted bitumen (water content
ranges from 10 mg∕ml to 500 mg∕ml) in a glass tube with a six-blade turbine.
Stirring speed of the turbine was 3600 rpm, and the mixing time was 10 min at
ambient temperature. K-F titration was performed to measure water content.
In order to test the lower limit of K-F titration, emulsion samples of diluted
bitumen (after centrifugation, dilution ratio N/В is 0.7) were diluted with toluene at
different ratio. K-F titration was performed to measure water content.
5.7.3. Results and discussions
5.7.3.1. Solvent selection for diluted bitumen
The default solvent for K-F titration is methanol, because methanol not only
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