Reactions during formation of PAM from 3BS-cured pastes

Reactions during formation of PAM from 3BS-cured pastes 

05 rel. dens, and the time of soaking is 10 min. Small regions of the pasted plates are sulfated during the soaking step. The chemical composition is determined through conventional analytical methods the potentials are measured vs. a Hg Hg2S04 reference electrode. 

Depending on the phase and chemical compositions of the paste and of the active mass, the formation process may be divided into two stages, as follows. 

For the above reactions to proceed, it is necessary that flows of H , SO , and H2O enter or exit the plate. These flows, together with the electronic charge shown in reaction Bi, maintain the electroneutrality of the solution in the reaction layer. The direction of each flow depends on the formation current as well as on the degree of sulfation of the cured paste and on the concentration of H2SO4 in the formation electrolyte [19,21]. 

The X-ray data for the phase composition of the Pb02 + PbS04 zone indicate that both the electrochemical reaction Bi and the reaction of sulfation Ei proceed in the same reaction layer. During the first stage of formation, there are two reaction layers in the plate. In the first layer, the electrochemical reaction Bi and the chemical 

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