Characterization of high-alumina coal fly ash based silicate material and its adsorption performance on volatile organic compound elimination

A highly stable silicate material from high-alumina coal fly ash was prepared and characterized using X-ray diffraction, scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, thermal analysis, X-ray photoelectron spectroscopy, and elemental analysis. The spectral results show that the silicate material was mainly composed of six elements, C, Ca, O, Si, Mg, and Al, in the form of Ca2+, Mg2+, Al3+, SiO32−, and CO32− ions. Some adsorbed water and/or water of crystallization was also observed. The silicate material showed exceptionally high capability to adsorb volatile organic compounds (VOCs). The results of dynamic adsorption behavior show that the silicate material presents similar properties with commercial activated carbon and stronger absorption properties than commercial diatomite for the adsorption of VOCs. The FTIR spectral results show weak hydrogen bonding interactions of the silicate material with three VOCs.