Preparation of mesopore-rich carbons using attapulgite as templates and furfuryl alcohol as carbon source through a vapor deposition polymerization method

Mesoporous carbons with specific surface areas in the range of 409-937 m² g^-1, mesopore volumes in the range of 0.55-2.26 cm³ g^-1 and mesopore volume fraction higher than 86% are prepared by using crude attapulgite, calcined attapulgite and HCl-treated attapulgite as inorganic templates and furfuryl alcohol as the carbon source through a vapor deposition polymerization (VDP) method at 130 °C. The influences of VDP time, the calcination temperature and HCl concentration on the pore structure of the resultant carbons are investigated. The results indicate that the optimized VDP time, the calcination temperature and the HCl concentration are 6 h, 800 °C and 5 M, respectively, and the corresponding carbons have the maximum surface areas and mesopore volumes. Adsorption of tannic acid on the mesoporous carbons in tannic acid aqueous solution with an initial concentration of 200 mg l^-1 at 20 °C reveals that the equilibrium adsorption capacities (q_e) are in the range of 111-464 mg g^-1. The mesoporous carbon prepared from attapulgite calcined at 800 °C (C-T₈₀₀-6) exhibits the highest specific surface area (937 m² g^-1), the largest mesopore volume (2.26 cm³ g^-1) and the highest q_e (464 mg g^-1) among all the resultant carbons.