Oxidative destruction of hydrocarbons on a new zeolite-like crystal of Ca12Al10Si4O35 including O2- and O22- radicals

To develop a nonmetal catalyst to decompose hydrocarbons, a new zeolite-like Ca12Al10-Si4O35 was prepared by calcining hydrogarnet, Ca3Al2(SiO4)(0.8)(OH)(8.8), a hydrothermal reaction product from a mixture of CaO, Al2O3 sol, and amorphous SiO2. The X-ray diffraction analysis showed the framework of (Al,Si)O-4 tetrahedra formed in the Ca12Al10Si4O35 crystal. ESR measurement and Raman spectroscopy revealed that both superoxide anions (O-2(-)) and peroxide species (O-2(2-)) existed in the cavity of the framework. Due to the O-2(-) and O-2(2-) species present, Ca12Al10Si4O35 exhibited high activity for the oxidation of hydrocarbons to carbon oxides (CO2 and CO) and H2O at > 400 degreesC.