Croatica Chemica Acta, Vol. 69 No. 1, 1996.
Original scientific paper
Catalytic Effect of 2,4- or 2,6-Diaminotoluene on the Electrochemical Reduction of Zinc(II) Ions
Grażyna Dalmata
; Faculty of Chemistry, M. Curie-Sklodowska University, PL M. Curie-Sklodowskiej 3. 20031 Lublin, Poland
Abstract
Adsorption of 2,4 and 2,6-diaminotoluene on the mercury/1 mol dm-3 NaC104 interface was examined. The differential capacity, potential of zero charge of mercury and the interfacial tension at PZC were measured. Surface concentrations were calculated on the basis of these measurements.
Rate constants of Zn(II) ion electroreduction in 1 mol dm-3 NaC104 in the presence of 2,4- and 2,6-diaminotoluene were determined by a cyclic voltammetry method. The catalytic activity of 2,4-diamino- toluene was found to be much higher than that of 2,6-diaminotoluene due to different orientation of these isomers on the electrode surface. From the temperature dependence of rate constants, the enthalpies of activation of zinc electroreduction AH* = 16.3 kJ mol-1 in the presence of 2,6-diaminotoluene and AH* - 0 in the presence of 2,4-diaminotoluene were determined.
Keywords
Hrčak ID:
135947
URI
Publication date:
4.3.1996.
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