Preparation and characterization of the carbon–Microsilica composite sorbent

In this paper, Microsilica, one kind of industry solid waste, was utilized firstly to prepare carbon–Microsilica composite sorbent with core–shell structures from a partial carbonization, mixture, and sulfonation process. The prepared composite sorbent was characterized with XPS, FT-IR, SEM, XRD and gas sorption experiments. The characterization results indicated BET surface area (SBET) and total pore volume (Vtotal) of the prepared composite sorbent enhance 255% and 136% than Microsilica, respectively, and an abundant of oxygen functional groups, such as carboxyl and sulfonic groups, were introduced into the surface of the prepared composite sorbent. The adsorption capacity of the prepared composite sorbent for methylene blue (MB) and Cr(VI) also was investigated and compared with Microsilica and activated carbon, the results shown that the adsorption capacity of the prepared composite sorbent for methylene blue and Cr(VI) enhance 406.6% and 657.5% than Microsilica, and reach about 70.0% and 72.3% of activated carbon adsorption capacity, respectively. This paper proposed a new approach of comprehensive utilization of Microsilica with a uncomplicated process, and the prepared carbon–Microsilica composite sorbent with excellent adsorbent performance could be used as a potential substitute of activated carbon for heavy metal ion or organic dye adsorption in waste water.