Electrocatalytic determination of phenylhydrazine in the presence ofhydrazine at the modified nano zeolite carbon paste electrode

Hydrazine and its derivatives are widely used in agriculturalchemicals (pesticides), chemical blowing agents,pharmaceutical intermediates, photography chemicals, andboiler water treatment in hot-water heating systems for corrosion control[1].Carbon paste electrode (CPE) is a special kind of heterogeneous carbon electrode consisting ofmixture prepared from carbon powder (as graphite, glassy carbon and others carbonaceous materials. Modification of cabon paste electrode using organic and inorganic materials pay much attention for electrooxidation of wide range of biological compond [2,3]. The purpose of this work is to electrocatalytic determination of phenylhydrazine in the presence of hydrazine the modified nano zeolite carbon paste electrode. The electrochemical behavior proposed electrode was investigated cyclic voltammetry and Differential Pulse Voltammetry. A mixture of appropriate amount of nanosized NiZSM-5and graphite powder,ferrosen and paraffin were blended by hand mixing with a mortar and pestle for preparation of zeolite modified carbon paste [ZMCP]. The resulting paste was then inserted in a glass tube. The electrical connection was implemented by a copper wire lead fitted into the glass tube. The carbone paste electrode (CPE), used for comparison, was prepared in the same way but omitting the zeolite and ferosen addition step. The oxidation of hydrazine was studied at CPE and fe/ZSM-5/CPE by cyclic voltametric experiment in buffer solution then obtained results was compared with each other. The percentage of zeolite, pH, scan rate of potential were studiied. Under optimal conditions, the electrochemical behavior of phenylhydrazine (phy) in the presence of hydrazine (hy) was investigated using 14th Annual Electrochemistry Seminar of Iran Materials and Energy Research Center (MERC), 12- 13 Dec, 2018 41 differential pulse voltammetry method. The linear dynamic ranges of 2.0× 10-5 -19×10-4 M and2.0× 10-5 -14×10-4 M for phenylhydrazine and hydrazine were obtained respectively. The detection limits were obtained 2.11 × 10-6 and 2.5 × 10-6 M, for (PHY) and (HY). The surface coverage coefficient (٭) and diffusion coefficient (D) were calculated 1.56× 10-6 and 0.55 mol / cm-2. Also, the electrochemical behavior of phenylhydrazine and hydrazine with a specific concentration were also investigated using a cyclic voltammetric method at different scans and the electron transfer coefficient was 0.44 and 0.42, respectively. The chronoamperometry technique was studied and the catalytic rate constant for electrooxidation of hydrazin and phenyl hydrazine were calculated to be 6.99×104 cm3.mol-1.s-1 and 2.02× 106 cm3.mol-1.s-1 respectively.The obtained results were show that proposed modified electrode was a sutable electrode for determination of phenyl hydrazine in the present of hydrazine.