The name is absent

Chapter 5

platinum electrodes. Prior to equivalence point, the solution contains Γ but little l₂.
At the equivalence point, excess I₂ appears and an abrupt current increase marks
end point. K-F titration has nearly unlimited measuring range (1ppm to 100%)^[11].

5.7.2. Materials and methods

5.7.2.1. Materials

K-F reagent is obtained from Sigma-Aldrich (Product# 36115-1L, around 5
mg water/ ml reagent, should be stored <15 ⁰C). Methanol and toluene used as
titration solvents are from EMD Inc. Titration system is Metrohm KF-701 Titrino.

Samples of Athabasca bitumen were provided by Syncrude Canada Ltd.
Bitumen samples were diluted with naphtha with dilution ratio 0.7. Most of the
solids and water can be removed by centrifugation process, with a centrifugal
acceleration of 8000 g and a centrifugation time of 30 min.

5.7.2.2. Solubilitytest Ofdiluted bitumen in toluene-methanol mixture solvent

Toluene-Inethanol mixture was prepared by mixing toluene and methanol
with different volume ratios. 1.0 ml diluted bitumen (dilution ratio N/В = 0.7) was
added to 25ml toluene-methanol mixture with electromagnetic stirring. After five
minutes, no precipitation indicates that the solvent can dissolve diluted bitumen
and can be used for titration.

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