Preparation of Sodium Humate/α-Aluminum Oxide Adsorbents for Flue Gas Desulfurization

Abstract

A new composite adsorbent of sodium humate (HNa)=alpha-aluminium oxide ({alpha}-Al{sub 2}O{sub 3}) for flue gas desulfurization (FGD) was prepared using the impregnation method. Both the adsorbent of {alpha}-Al{sub 2}O{sub 3} and HNa={alpha}-Al{sub 2}O{sub 3} were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), energy dispersive X-ray spectrometer (EDS), and scanning electron microscope (SEM). Desulfurization activity of the adsorbent impregnated with ammonia (NH{sub 4}OH) was investigated in a fixed-bed quartz reactor. Experimental results indicate that HNa, which coats the {alpha}-Al{sub 2}O{sub 3} fibers impregnated with HNa solution, improved the property of {alpha}-Al{sub 2}O{sub 3} support for FGD. On the other hand, the HNa-coating on the adsorbent of HNa/{alpha}-Al{sub 2}O{sub 3} impregnated with NH{sub 4}OH played an important role in enhancing the desulfurization property of the {alpha}-Al{sub 2}O{sub 3}. Due to the strong adsorption capability of HNa, more NH{sub 4}OH was adsorbed in the adsorbent of HNa/{alpha}-Al{sub 2}O{sub 3} the longer a high sulfur dioxide (SO{sub 2}) conversation rate was maintained. In addition, because the desulfurization product was a compound fertilizer consisting of ammonium sulfate ((NH{sub 4}){sub 2}SO{sub 4}), ammonium humate (HNH{sub 4}), and HNa, the recycling use of {alpha}-Al{sub 2}O{sub 3} was also easily achieved. Thus, this study canmore » provide a new cost-effective way to remove SO{sub 2} from flue gas.« less