Voltammetric Studies in Phosphorous Oxychloride Solutions Containing Lithium Tetrachloroborate.

摘要

The electrochemical reduction of phosphorous oxychloride in 0.1, 0.5, and 1 molar LiBCl4-POCl3 solutions was studied at pyrolytic graphite and glassy carbon microelectrodes using the techniques of cyclic and rotating ring-disc voltammetry. It is shown that the reduction of phosphorous oxychloride in these solutions occurs through an intermediate POCl2 free radical species which can be collected at the ring electrode in the ring-disc experiments and reoxidized to POCl2(+) species at more positive potentials. The small collection efficiency (0.002) in these experiments, however, indicated that the intermediate POCl2 free radical species has a short lifetime and disproportionates rapidly to give the final reduction products. It was also shown that the cathodic and anodic potential limits in LiBCl4-POCl3 solutions were, respectively, caused by the deposition of lithium metal at the cathode and liberation of chlorine gas at the anode.