Forming Active Carbon Monoliths from H3PO4-loaded Sawdust with Addition of Peanut Shell Char

Abstract

Peanut shell char (PSC) was converted into active carbon monoliths (ACMs) by adding a binder that was easy to make. The conversion process involved adding the PSC into H3PO4-loaded sawdust, extruding the mixture, and finally heating the resulting monoliths for different times. The properties of the resulting ACMs were investigated using scanning electron microscopy, energy dispersive X-ray spectroscopy, Fourier transform infrared analysis, nitrogen adsorption-desorption, X-ray diffraction, and thermogravimetric analysis. The H3PO4-loaded sawdust could be used as a binder for converting powdered PSC into well-shaped ACMs without visual cracks. The resulting ACMs maintained their monolithic shape, even in water. The ACMs showed a much higher specific surface area (SSA, 850 to 915 m2/g) than the PSC (105 m2/g). The largest SSA (915 m2/g) was achieved by activation for 50 min. Increasing the activation time decreased the SSA and apparent density, but only slightly impacted the carbon structure. This research might lead to value-added conversion of bio-chars.