Effective removal of methane using nano-sized zeolite 4A synthesized from kaolin

The purpose of this study was to synthesize nano-sized zeolite 4A from kaolin obtained from Guizhou New Materials Technology Co., Ltd. The properties of the nano-sized zeolite 4A were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR), 29 Si magic-angle spinning (MAS)-nuclear magnetic resonance (NMR) and 27 Al MAS-NMR, X-ray fluorescence (XRF), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET), and thermogravimetry (TG)-differential thermal analysis (DTA). According to SEM studies, it can be concluded that the nano-sized zeolite 4A has a typical cubic morphology. TEM images validate that the nano-sized zeolite 4A is of 100–150 nm in size. From the selected-area electron diffraction (SAED) patterns, it is confirmed that these nano-sized zeolite 4A particles have a pure body-center-cubic structure. The textural properties of the nano-sized zeolite 4A were studied by nitrogen adsorption technique, and it can be concluded that the BET surface area of the nano-sized zeolite 4A is 25.131 m 2 ·g −1 . In addition, it is found that the Langmuir model is best suited for the adsorption isotherms of methane on nano-sized zeolite 4A. Meanwhile, the methane adsorption analysis confirmed that the maximum adsorption amount of the nano-sized zeolite 4A to methane increases with the increase of adsorption temperature in the temperature range of 288–318 K.