Synthesis of porous cordierite and application for MnO x /TiO2 catalyst support

Abstract

In this study the porous cordierite supports were synthesized from kaolin, magnesium oxide, silicon dioxide, and starch as pore-forming agent. A firing temperature, a optimum added amount of the starch, an acid treating time, and impregnation times for the cordierite support were all discussed. The results showed that when the firing temperature was 1300°C and the amount of the pore-forming agent was 8%, the bending strength and thermal expansion coefficient of the cordierite sample were 19.48 MPa and 1.94 × 10−6 °C−1, respectively, which fitted for MnOx/TiO2 SCR catalyst’s support. The FTIR indicated that it was necessary for the cordierite to be treated by 2mol L−1 nitric acid, this process could introduce a larger number of oxygen-containing functional groups and create a more hydrophilic surface structure. The SEM images illustrated that the acid treatment resulted in developing the amount of pores, which contributed to the gas-solid phase reaction. When the cordierite supports were impregnated 5 times in the MnOx/TiO2 solution, a loading amount of MnOx/TiO2 was 20.05%. With this MnOx/TiO2/cordierite samples, the maximum NO conversion could reach 85.4% at 200°C, which met the requirement of cement industry for selective catalytic reduction (SCR) with NH3.