Surface Area and Spring Lengths between Two Cubic Volumes Structure of the Activated Carbon Pellets


A series of activated carbon pellets (ACPs) prepared from pre-carbonized palm leaves treated with KOH having a concentration of (0.0 - 0.07) by moles (M) for carbonization at different temperatures from 500°C to 1000°C in a nitrogen environment, using a milt step heating profile. The experimental sets were carried out to characterize the crystallite units, specific surface area and spring length between two cubic volume granular structures. The crystallite units such as interlayer spacing (d002), layer height (Lc ) and layer diameter (La ) were analyzed using the wide-angle X-ray Diffraction (XRD). The ultrasonic technique was used to measure the longitudinal velocity (V). The XRD analysis found that the structure of all the ACPs produced is turbostratic, showing that the activated carbon prepared below 1000o C has a disordered structure containing defective layer planes, which is expected to occur in small crystallite units. The d002 values were increased with KOH concentration and decreased with increasing carbonization temperature and becomes very dependent on 1/La at a higher carbonization temperature. The Lc and La values were found to increase linearly with increasing carbonized temperature. The specific surface areas (SSA) were estimated by the layer height (Lc) and bulk density (ρ). The specific surface areas (SSA1) were further estimated by a mathematical model given by Emmerich FG and CA Luengo by substituting the bulk density (ρ). The results show fair agreement between SSA and SSA1 for the ACPs, treated with 0.02 M, 0.06 M and 0.07 M KOH. The spring length of two cubic volume granular structures was decreased with increasing KOH concentration. Our results proved the capability of the mathematical model to estimate specific surface area in terms of longitudinal velocity and crystallite units. The results also show that it is possible to prepare activated carbon with high surface area.