Catalytic Activity for Decomposition of Hydrogen Peroxide by Metal Complexes of Water-Soluble Thiacalix[4]arenetetrasulfonate on the Modified Anion-Exchangers

Abstract

The catalytic activity for the decomposition of hydrogen peroxide by anion-exchangers modified with metal complexes of thiacalix[4]arenetetrasulfonate (Meⁿ⁺-TCAS[4], Meⁿ⁺=Mn³⁺, Mn²⁺, Fe³⁺, Co³⁺, Co²⁺, Cu²⁺, Zn²⁺ and Ni²⁺) was investigated. As a reference, calix[4]arenetetrasulfonate, calix[6]arenehexasulfonate and calix[8]areneoctasulfonate were also examined. Mn³⁺- and Fe³⁺-TCAS[4] on the modified anion-exchangers showed high catalytic activity in alkaline buffer solutions among metal complexes tested. Mn³⁺- and Fe³⁺-TCAS[4] on the modified anion-exchangers exhibited high and constant levels of catalytic activity even after having been used 5 times, and showed catalytic activity in the presence of an excess of H₂O₂ over Mn³⁺- and Fe³⁺-TCAS[4] on the modified anion-exchangers. Only Mn³⁺-TCAS[4] on the modified anion-exchangers exhibited high catalytic activity at around a neutral pH.