Novel “Flow Injection” Channel Flow Cell for the Investigation of Processes at Solid−Liquid Interfaces. 1. Theory

A novel “flow injection” channel flow cell is described which enables transient phenomena at the solid−liquid interface to be investigated. In the cell the solution reactant is injected into the main channel of a flow cell upstream from, and through the opposite wall from, the solid substrate. A detector electrode is positioned downstream of the latter so that current−time transients can be used to infer the kinetics and mechanism of processes at the solid−liquid interface. The performance of the cell was theoretically modeled using FLOTRAN. It was shown that the “injection” of reactant causes only very minor disturbance to the main channel flow. This facilitates the assumption of Poiseuille flow in the channel so as to enable the numerical interpretation of the current−time transients.