Simultaneous determination of rare earth elements in ore and anti-corrosion coating samples using a portable capillary electrophoresis instrument with contactless conductivity detection

• Simple and inexpensive method for determination of rare earth elements with portable CE-C4D.
• A new arrangement for the portable CE-C4D instrument is reported.
• The method was applied for determination of rare earth elements in ore and anti-corrosion coating samples.
• Good agreement between results from CE-C4D and the confirmation method (ICP-MS) was achieved.

The employment of an in-house-made capillary electrophoresis (CE) instrument with capacitively coupled contactless conductivity detection (C4D) as a simple and inexpensive solution for simultaneous determination of many rare earth elements (REEs) in ore samples from Vietnam, as well as in anti-corrosion coating samples is reported. 14 REEs (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu) were determined using an electrolyte composed of 20 mM arginine and 10 mM α-hydroxyisobutyric acid adjusted to pH 4.2 with acetic acid. The best detection limit achieved was 0.24 mg/L using the developed CE-C4D method. Good agreement between results from CE-C4D and the confirmation method (ICP-MS) was achieved, with a coefficient of determination (r2) for the two pairs of data of 0.998.