A Mo/MoO_2 Electrode for Use of Corrosion Control in Absorption Refrigeration Systems

摘要

A new electrode, Mo/MoO_2 has been proposed for the purpose of better control of corrosion inhibition of constructive materials in adsorption refrigeration systems. The electrode is prepared by heating a molybdenum rod in air at 873 K followed by reduction in hydrogen at 723 K. The potential of the electrode was stable in LiBr solutions of wide range of temperature (298-428 K), concentrations of LiBr (2, 17.3 mol kg~(-1)), LiOH (10~(-3)-10~(-1) mol kg~(-1)), Li_2MoO_4 (10~(-4)-10~(-2) mol kg~(-1)) and LiNO_3 (0-10~(-2) mol kg~(-1)). The potential of the electrode responded to the concentration of LiOH while not to those of Li_2MoO_4 and LiNO_3. The electrode potential was changed sharply by introducing oxygen into the solution at 353 K in 2 mol kg~(-1) LiBr solution. But it became less clear at 428 K in 17.3 mol kg~(-1) LiBr solution. The electrode can be used as a sensor for the concentration of LiOH. Another application of the electrode would be a quasi internal reference electrode in a commercial machine for the monitoring of corrosion potential of steels.