Core-shell granular activated carbon and its adsorption of trypan blue

Granular activated carbon (GAC) and powder activated carbon (PAC) have many disadvantages that limit their application as adsorbent. Thus, a novel core-shell granular activated carbon ([email protected]) was designed and can be used to adsorb trypan blue. [email protected] was prepared using PAC as the core and wood powder and silica sol as the shell. The preparation was achieved by a facile method. The morphology and pore structure of the developed [email protected] were observed by scanning electron microscopy, and its N2 adsorption-desorption isotherm was determined. [email protected] was obtained under the optimal conditions where the wood powder/core ratio was 0.40, silica sol/wood powder ratio was 2.0, and heat treatment was at 250 °C for 1.5 h. The results showed that the [email protected] had a specific surface area of 1127.8 m2/g and the abrasive resistance of 99.24%. The adsorption of trypan blue experiment showed that PAC and PAC in [email protected] ([email protected]) reached the highest adsorption capacity of 115.6 mg/g and 113.2 mg/g, respectively, which further showed that the adsorption capacity of [email protected] was fully utilized. The results also showed that the [email protected] was able to overcome the disadvantage of GAC where the superficial carbon could block the adsorption of trypan blue from the core carbon, thus improving the efficiency of adsorption. This work provides a foundation for the production and development of GAC, as well as other particle adsorbents or catalysts.