Activated carbon/attapulgite composites for radon adsorption

•AT can easily diffuse into activated carbon to prepare AC/AT composites.•AC/AT composites contain more micropores than activated carbon.•AC/AT composites have high radon adsorption capacity.•AC/AT composites exhibit excellent cyclic adsorption stability. In order to improve the radon adsorption capacity of activated carbon (AC), one-dimensional nano attapulgite (AT) was filled into the macropores and mesopores of activated carbon, and sintered to prepare activated carbon/attapulgite (AC/AT) composites with more abundant micropores. The effect of AT on the structure and radon adsorption capacity of activated carbon was studied in detail. The results show that AT can easily diffuse into the macropores and mesopores of activated carbon to form a new hierarchical porous network, which significantly increases the specific surface area and proportion of micropores of activated carbon. The as-prepared AC/AT composites exhibit excellent radon adsorption and regeneration performance. With the filling content of AT ranging from 0 to 3%, the radon adsorption coefficient increases from 4.28 L/g to 5.35 L/g, and maintains 92.7% of its initial value after 5 adsorption-desorption cycles.