Effects of micropore size of activated carbon fibers prepared by steam activation on toluene adsorption
摘要
Activated carbon fibers (ACFs) are highly effective adsorbents for gas separation, water purification, and hazardous gas removal owing to their substantial specific surface area and adjustable pore structure. This study investigated how the pore size of ACFs influenced the adsorption of toluene, a volatile organic compound (VOC). To modulate the pore size, ACFs were synthesized at various steam flow rates during steam activation. All samples demonstrated adsorption efficiencies exceeding 99%, with a maximum capacity of 0.418 g/g, but micropores within the 0.65 to 0.85 nm range proved most effective. Among the samples, ACF0.8 showed the highest adsorption capacity and the longest breakthrough time. Correlation analysis revealed a positive trend between toluene uptake and total ultramicropore volume (R² = 0.84), whereas the 0.65–0.85 nm pore range exhibited a significantly closer association with adsorption capacity (R² = 0.98). These results indicate that controlling the steam flow is a viable strategy for optimizing micropore characteristics, offering practical design guidelines for the development of high-performance ACF-based VOC adsorbents.