Bimetallic Mn-Ce oxides modified α-Fe2O3 nanorods for low temperature catalytic thermal desorption of naphthalene in soil

Abstract

Developing highly active catalytic thermal desorption system is of great significance to soil remediation in a sustainable manner. Herein, Mn-Ce oxides modified α-Fe2O3 nanorods were fabricated for catalytic thermal desorption of naphthalene. When N2 was injected at 500 mL/min and heated at 180 °C for 5 min, the removal rate of naphthalene in soil by Ce-Mn/α-Fe2O3 reached a maximum of 99.96 %, and the corresponding removal rate achieved 32.1 %. Such excellent catalytic performances can be attributed to the mutual conversion of oxidation valence states of MnOx, CeO2, and Fe2O3, which enhance the oxygen mobility of the catalyst surface, resulting in abundant oxygen vacancies and acidic sites. Combined with the tests of GC–MS and FT-IR, the degradation intermediates were identified and a probable reaction pathway was proposed. This study provides an economical and efficient strategy for the enhancement of catalytic thermal desorption, showing crucial practical significance for PHAs remediation in soil.