Modification of a PVC-membrane electrode by surfactant modified clinoptilolite zeolite towards potentiometric determination of sulfide

作者：Nezamzadeh Ejhieh Alireza^*; Afshari Elham

来源：Microporous and Mesoporous Materials, 2012, 153: 267-274.

DOI：10.1016/j.micromeso.2011.12.054

• Potentiometric sensor
• Sulfide selective electrode
• Clinoptilolite zeolite
• Surfactant modified zeolite
• Hexadecyltrimethyl ammonium bromide

A modified PVC membrane with surfactant modified natural clinoptilolite zeolite as an ionophore along with dibutyl phthalate as a solvent mediator in the ratio of 30:66:4 (w/w) (PVC-DBP-ionophore) exhibits good behavior with a Nernstian response of 29.4 +/- 0.8 mV per decade of activity for sulfide ions and a working concentration range of 1.0 x 10(-7)-1.0 x 10(-1) mol L-1 sulfide. The limit of detection was 6.3 x 10(-8) mol L-1 sulfide. The sensor has a fast response time of 7-10 s and can be used for at least 8 weeks without any divergence in potential. The electrode can be used in the pH range of 3-10. The selectivity coefficients for sulfide relative to a numbers of potential interfering anions were investigated and the obtained results showed that the monovalent anions much interfere than multivalent anions. The practical utility of the sensor has been demonstrated by using it successfully as an indicator electrode in the potentiometric titration of S2- with Zn2+, Cu2+ and also for the direct determination of S2- in waste water samples.

• 出版日期2012-5-1