Evaluation of porous nickel hydroxide electrode for the oxidation of aliphatic and aromatic primary alcohols

Abstract

The positive plate of Ni-Cd battery was evaluated as Ni(OH)₂/NiOOH electrode for the oxidation of six aromatic and five aliphatic alcohols. In addition to galvanostatic preparative electrolysis, cyclic voltammetric experiments were also carried out. The anode material after electrolysis was evaluated using SEM and XRD. Except in the case of chlorine substituted aromatic alcohols the nickel hydroxide electrode showed excellent stability even after the reuse for nearly 10-15 times. In 0.1 M KOH containing 67% tertiary butanol + 33% water as electrolyte, aromatic alcohols gave predominantly aldehyde in good yield. In alkaline solutions without the co-solvent tertiary butanol aromatic alcohols were oxidized to their corresponding carboxylic acids. Short chain aliphatic alcohol (C5) gave reasonable yield of carboxylic acid. Long chain alcohols showed limited solubility in alkaline medium with and without co-solvent tertiary butanol and the yields of carboxylic acids were also poor.