Birnessite MnO2 supported on CNTs in-situ for low-temperature oxidation of ethyl acetate

Abstract

AbstractThe removal of ethyl acetate has received much attention because excessive emissions of ethyl acetate are harmful to the environment and human health. Efficiently removing ethyl acetate under high space velocity requires low-cost catalysts operating at low temperatures. Herein, carbon nanotubes (CNTs) supported birnessite MnO2 catalysts were in-situ prepared by the redox reaction between KMnO4 and CNTs to maximize the interaction between MnO2 and support. The good thermal stability derived from the intact CNTs structure was important for the interaction between MnO2 and CNTs, contributing to the enhanced catalytic activity for ethyl acetate oxidation. 4MnO2-CNTs showed outstanding performance for the catalytic oxidation of ethyl acetate (100 ppm), achieving 100% removal efficiency and 99% CO2 selectivity at 160 °C under 100,000 mL·g−1·h−1 space velocity. In addition, 4MnO2-CNTs exhibited an excellent catalytic stability during the 50 h test period. Based on the comprehensive characterization study, we revealed that the activity of 4MnO2-CNTs could be effectively enhanced by the higher amount of active sites (Mn3+ and surface active adsorbed hydroxyl oxygen), as well as the strong interaction between MnO2 and support and the good thermal stability derived from the introduction of the intact CNTs structure.