Improvements in char yield and pore properties of wood-derived carbon by iodine treatment

An iodine treatment was applied to wood to seek improvements in char yields and pore-related properties, i.e., surface area, micro-pore volume and its pore-size distribution, of the resultant wood-derived carbons without any other special pre- and post-treatments. Char yields were improved, surface area and micro-pore volumes were increased. The initiation temperature of pyrolysis of the treated woods was decreased, and gases such as CH3I and HI were produced during the pyrolysis. The change in the above-mentioned yields and pore-related properties with the iodine treatment was analyzed using wood-component polymers such as cellulose and lignin. By spectroscopic analyses, iodine in the polymers exists in its ionic state, which may increase the stability of the polymers. Iodine-treated lignin plays a role of the modification of the pyrolysis process in the improvements in the yields and pore-related properties in the resultant wood-derived carbons.