Synthesis of Porous Carbon for Acetone Adsorption: Specific Surface Area, Porous Structure and Oxygen Functional Groups

Abstract

AbstractThe porous carbon material is widely used as acetone adsorbent. The low‐cost, facile and efficient synthesis method of porous carbon material is of great significance to the removal of acetone. Potassium citrate, a common organic salt, was self‐activated in the current study at the temperatures of 600–900 °C to form porous carbons (KAC−X) with rich microporous structures. The KAC−X showed excellent specific surface area (763–2100 m2 g−1) and oxygen content (5.95–16.29 wt%). The sample obtained at the temperature of 900 °C showed promising acetone adsorption capacities of 8.33 mmol g−1 (15 °C) and 7.27 mmol g−1 (25 °C), respectively. The acetone adsorption results were well fitted by the Langmuir‐Freundlich and Freundlich models. Moreover, the influence of physical structure and oxygen functional group on the acetone adsorption performance was explored. The results showed that: (1) one of the main methods for promoting the acetone adsorption capacity is to increase the specific surface area; (2) the other method is to increase the optimal pore volume, and the optimal pore size is 2–5 times of the acetone molecule diameter; (3) carboxyl and carbonyl groups can significantly increase the adsorption affinity between acetone molecule and KAC−X, and play an auxiliary role on the acetone adsorption. This study provides guidance for the facile synthesis of porous carbons from organic salt for the sake of acetone adsorption.