Frans_M_Everaerts_Isotachophoresis_378342.pdf

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SEPARATION OF ANIONIC SPECIES IN AQUEOUS SOLUTIONS
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Fig.12.3. Isotachopherogram of the separation of some anions carried out in the operational system
listed in Table 12.2 @H 7). 1 = Chloride; 2 = sulphate; 3 = oxalate; 4 = chlorate; 5 = formate;
6 = pyrazole-3,5-dicarboxylate; 7 = adipate; 8 = iodate; 9 = P-chloropropionate; 10 =nicotinate;
11 = ascorbate. The current was stabilized at 70 PA. If this isotachopherogram is compared with those
in Figs.12.1 and 12.2, it can be seen that the resolution is smaller, although separations are still possible.
12.2. SEPARATION OF ANIONIC SPECIES IN AQUEOUS SOLUTIONS USING A
CONDUCTIVITY DETECTOR (a.c. METHOD) AND A UV ABSORPTION DETECTOR
(256 nm)
12.2.1. Introduction
In this section, we consider isotachophoretic separations in four operational systems
with water and deuterium oxide. The pH values were chosen arbitrarily as 7.5 (Table 12.4),
6 (Table 12.1), 4.5 (Table 12.5) and 3 (Table 12.6). The results obtained in these systems
are listed in Table 12.7 for water and Table 12.8 for deuterium oxide.
The analyses discussed in section 12.2.2 were carried out mainly in these operational
systems, although the pH, for optimal separation, may be chosen to be higher or lower
than those given in the tables.
The analyses were carried out with the equipment described in section 7.4.4.