Investigation of the reactivity of powder surfaces by abrasive voltammetry

The ability of abrasive voltammetry to reflect the reactivity of iron powde r immobilized on paraffin-impregnated graphite electrodes was investigated. Normal pulse voltammetry was used as the preferred method. The peak shape and position on the potential/time axis reflected both the reactivity of ir on powder particles as well as their size fraction. "Relative peak height" defined as peak height to area ratio, i.e., current to charge ratio, correl ated well with the rate of the electrochemical dissolution process. It show ed not only a decreasing dissolution rate with an increase in particle size , but also the differencies in the dissolution rate of iron powder of vario us reactive surfaces as a consequence of various pretreatment methods. It w as found that chemical pretreatment of the powder always resulted in a fast er dissolution process in comparison with other non-chemical pretreatment m ethods.