• hexadecyl trimethylammonium ion;
  • bentonite modified electrode;
  • phenol;
  • reaction order;
  • Tafel slope

In this article partial and complete substitution of cations in the interlayer region of clay with different amounts of hexadecyl trimethylammonium bromide (HDTMABr) was performed. The aim was to investigate the influence of HDTMA/bentonite ratio on phenol electrooxidation. Multisweep cyclic voltammetry was applied to analyze the behavior of clay modified glassy carbon electrode. The influence of phenol concentration was investigated. HDTMA/clay ratio plays key role in phenol oxidation on these electrodes. There is definite amount of surfactant that should be present in bentonite sample in order to achieve good current response and prolonged life of the electrode. The reaction order in respect to phenol was determined to be around 2. © 2012 American Institute of Chemical Engineers Environ Prog, 32: 1124–1128, 2013