Hierarchical porosity, Carbon monolith, Soft-templating, Kinetics of adsorption, Di?usion

An easy synthesis of carbon monoliths with hierarchical porosities is presented here combining phenolic sol-geland soft-templating methods (use of amphiphilic surfactant Pluronic F127 as mesopores template). By varyingthe synthesis conditions, purely microporous or micro-mesoporous or micro-meso-macroporous carbon materialswere obtained. While micropores and mesopores arise during the carbonisation, macropores formation occursduring the gelling step through a controlled macroscopic phase separation process. The same pyrolytic tem-perature was used to ensure comparable surface chemistry (proved by FTIR and TGA-MS measurements for thetemplated samples), textural properties were investigated by a group of techniques: TEM, CO2and N2sorption,Hg porosimetry and SAXS. The bene?t of the di?erent porosities was evidenced on blocs of 1-2.5 mm diameterby studying adsorption kinetic of phenol and methylene blue aqueous solutions. Due to comparable surfacechemistry of the templated samples, only their di?erence of porosity was considered as a decisive factor for thekinetics of adsorption. The relative role of each porosity was evidenced and quanti?ed. It was found that me-sopores are crucial for a fast transport of adsorptive into the adsorption sites (micropores/smaller mesopores)while the additional presence of macropores further accelerates the rate of sorption for both adsorptives.