Potentiometric Analysis of Samarium Ion in Aqueous Solution Employing Selective Electrode Based on Crown Ethers - Samarium Picrate Complexes in a PVC Membrane

Abstract

Samarium  ion selective  electrodes  we1·e  construct.ed  and  prepared

then  tested as  probefor  Samarium  ion detection  and determination  in different aqueous solutions.

The sensitive membrane is made of  PVC which contains Samarium

picrate complexed with either 18-crown-6 or 15-crown-5 ethers as active species.

Different  plasticizers:  phthalates  (DBPH),  phosphates  (DBP)  and

phosphonates  (DOPP) were incorporated into the membranes as solvent

mediators.

Every   membrane   was   evaluated   practically   following   standard

proced ures to find out its reliability and durability as a probe suitable for analytical application.

Linear working range, Ncrnestain slope, detection l imit, measurement stability, response time  and electrode  l ife tirnc were calculated  for each electrode.

The l inear concentration range for most ol'the electrodes were from

-      _,

10 to 10 molar Sm (III), the slope was 18 mv/decade to 20 mv/decade whi l e

the working pH range was from 3 to 8.

Cations interference and anion radicals Na+, Ca2+, La"+, Nd '+ have

no effect on the measurement selectivity except  in the presence M (Ill)

ions.