Characterization of activated beech wood char – Methane storage application

Abstract

Commercial beech wood char characterized by low volatile matter (5.3%) and high carbon content (94.5 %) was initially used as a potential feedstock to obtain the activated carbon for methane sorption. Micro-and mesopores volumes were determined to be at the level of 0.21 cm 3 ∙g -1 , while the specific surface area of the material was determined to be at the level of 416 m 2 ∙g -1 . Carbonization carried out at the temperature range of 750-900 o C resulted in slight increase of the pore volume (up to the value of 0.23 cm 3 ∙g -1 ) and the specific surface area (up to the value of 480 m 2 ∙g -1 ). Upon the steam activation (up to the 50 % loss of the organic mass) the specific surface area increased substantially and was within the range of 887-943 m 2 ∙g -1 together with mico-and mesopores volumes that was within the range of 0.54-0.58 cm 3 ∙g -1 . The maximum methane adsorption was determined for the sample activated at a temperature of 800 o C – 17.7 g∙kg -1 with a process reversibility of 84.2%. Considering the beech wood char price, its availability and well-known methods of its surface structure improvement, the obtained active carbons are interesting for their testing on a larger scale.