Adsorption characteristics of activated carbon for siloxanes

• Activated carbons (ACs) showed high siloxane (D4) adsorption capacity.
• BET surface area of the AC was positive related to D4 adsorption capacity.
• Micropore volume was positive related to D4 adsorption capacity.
• Pores with diameter of 1.7–3.0 nm are the most favorable pores for D4 adsorption.

The adsorption capacity of several kinds of activated carbons (ACs) for octamethylcyclotetrasiloxane (D4) in simulated landfill gas (LFG) was investigated and the main textural characteristics for AC adsorptive removal of siloxanes were studied. It was found that most of the ACs employed in this work showed good D4 adsorption capacity, and the D4 adsorption capacities of them ranged from 21.94 mg/g to 224.63 mg/g. Positive correlation was observed between D4 adsorption capacity and the BET surface area and the micropore volume of these ACs. Through analyzing nitrogen adsorption isotherms of these ACs, a conclusion was made that the super micropores and small mespores (pores of diameter ∼ 1.7–3.0 nm) in the ACs are the most favorable pores for siloxane adsorption.