Synthesis of bentonite/Nano-Mn3O4 composite material and degradation of formaldehyde

Abstract

In order to obtain more efficient catalytic materials for degrading the air pollutant - formaldehyde, Nano-Mn₃O₄ and bentonite / Nano-Mn₃O₄ composite catalysts (BMC) for formaldehyde degradation were prepared by sol gel method, using manganese sulfate, bentonite, citric acid and ammonia as reactants. Field emission-scanning electron microscope, Transmission electron microscope, X-ray Diffraction, Nitrogen adsorption experiments and laser particle size analyzing instrument have been employed to characterize the Mn₃O₄ and BMC nanoparticles, respectively. The mechanism and effect of formaldehyde degradation of these substances are also discussed. The results show that BMC catalytic material has a better ability to degrade formaldehyde in air than Mn₃O₄ at the room temperature, which is resulted by the strong adsorption capacity of bentonite providing a reaction site and molecular collision site for oxidative decomposition of formaldehyde. And the synthesized catalytic materials have the advantages of low cost, easy regeneration and recycling.