Frans_M_Everaerts_Isotachophoresis_378342.pdf

SEPARATION USING CONDUCTIVITY AND UV DETECTORS 305
An injection was made of an industrial sample that contained the chloride ion and the
isotachopherograms shown in Fig.12.7 were obtained. No attention will be paid to the
mixture of anions (x).
In Fig.l2.7a, it is clear that the chloride ion is more mobile than the Fe(CN6)4- ion.
This can be seen in the UV trace and the linear trace of the conductivity detector. -. It
should be noted that the concentration of the original Fe(CN6)& thistidine is not changed
after the passage of the chloride ion, which can be seen in the linear trace of the conductivity
detector and the linear trace of the W absorption detector [Fe(CN,)4- has a W
absorption]. In Fig.12.7b, a mixed zone between Cl- and Fe(CN6>e can be seen. In
Fig. 12.7c, Fe(CN6)4- is moving in front of Cl-.
2+3+
I--
"f
-
-+t
c ! : I
t
t I- 1"
r I b C
Fig.12.6. Separation of nitrate andsulphate in the operationalsystemat pH 6 (Table 12.1) withwater
and deuterium oxide as the solvents. The difference in solvation of these two solvents is clearly visible.
1 = Chloride; 2 = nitrate; 3 = sulphate; 4 = acetate. The current was stabilized at 70 PA. A = Increasing
W absorption; R = increasing resistance; t = time.