Filter the electrolyte

Wherever the outlet is, a strainer/filter of at least 40 mesh screen should be placed over the outlet on the inside of the reservoir and epoxied in place. If a pre-pump filter is placed just before the pump in the system, this is not necessary. However, the screen is less expensive than buying a pre-filter, and it is easy to make. 

Tanks can be purchased from such suppliers as McMaster-Carr, Aquatic Ecosystems and US Plastics. These may already have outlets, or not. 

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The conditions (6.3.5a,b) merely state that at the outer edges of the filter the electrolyte concentrations are assumed fixed equal to the bulk concentrations in the vessels I and II. Conditions (6.3.5c,d) fix the electric potential and the pressure at the left I edge of the filter at zero reference level. Condition (6.3.5e) is just a combination of (6.1.1), (6.1.2) of 6.1, N is the average number of pores per unit cross-sectional area of the filter. 

Stock solution of nitrite, 5 mol/L Prepened by dissolution of the sodium salt in 500 mL of water. This solution is the main source of the reagent cobalt contribution. Cobalt contamination in this solution is removed by electrolysis (24 h) above a mercury pool electrode at a potential of -1.35 V. Alternatively, hydrous manganese dioxide (Mn02) can be added to a final concentration of 100 /tmol/L followed by filtration (0.2 pm filter). The electrolytic purification lowers the cobalt contribution to below 4 pmol/L. 

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