INFLUENCE OF ZnCl2 CONCENTRATION ON THE SELECTIVITY OF A Zn(NCS)4²--SELECTIVE ELECTRODES AND ITS APPLICATION FOR DETERMINATION SCN- IONS IN INDUSTRIAL SOLUTIONS
The influence of the background concentration of ZnCl2 on the selectivity of Zn(NCS)4(2-)−SE based on QAS to SCN- is studied. The introduction of ZnCl2 into a solution fixes zinc released from the membrane in the form of thiocyanate complex. A high selectivity of the Zn(NCS)4(2-)−...
| Autores: | , |
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| Tipo de recurso: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 2017 |
| País: | Chile |
| Institución: | Agencia Nacional de Investigación y Desarrollo |
| Repositorio: | SciELO Chile |
| OAI Identifier: | oai:scielo:S0717-97072017000200011 |
| Acceso en línea: | http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-97072017000200011 |
| Access Level: | acceso abierto |
| Palabra clave: | potentiometry thiocyanate ions tetrathiocyanozincate-selective electrode quaternary ammonium salts |
| Sumario: | The influence of the background concentration of ZnCl2 on the selectivity of Zn(NCS)4(2-)−SE based on QAS to SCN- is studied. The introduction of ZnCl2 into a solution fixes zinc released from the membrane in the form of thiocyanate complex. A high selectivity of the Zn(NCS)4(2-)−SE to SCN- ions is due to the formation of better extractable complexes between zinc and SCN- compared to acidocomplexes of competitive anions. An introduction of 5.0 M ZnCl2 into a solution increases selectivity to SCN- ions by 5 orders of magnitude in the presence of interfering CKO4- ions and more than 4.5 orders of magnitude in the presence of interfering NO3- ions. |
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