Synthesis of diphenylamine by condensation of aniline catalyzed by microporous-mesoporous composite solid acid nanoreactor

Microporous zeolite has regular pores, good surface properties and strong thermal and hydrothermal stability, but the adsorption and diffusion of macromolecules are limited by small and narrow pores, and the active sites of pores are difficult to use effectively. Mesoporous materials have good pore structure, but poor thermal and hydrothermal stability and weak acidity. In order to overcome the structural defects of single channel catalyst, a series of beta zeolite and activated clay composite solid acid catalysts were prepared in this paper. X-ray diffraction and N-2 physical adsorption-desorption showed that the composite catalyst has a microporous-mesoporous composite structure. The synthesis of diphenylamine by aniline condensation proved that the composite catalyst can be used as nanoreactor to promote the reaction. Combined with pyridine adsorption infrared spectroscopy, thermogravimetry, scanning electron microscope and kinetic analysis, the catalytic mechanism of microporous-msoporous composite solid acid nanoreactor was explored.