Molded charcoal prepared from bark charcoal and wood pyrolysis tar

Bark chips of Acacia mangium, which are produced as wood waste by an Indonesian pulp factory, were carbonized to powdered charcoal at a temperature range between 300 similar to 400 degrees C. The by-product, tar, was mixed with the powdered charcoal, molded, and formed into charcoal having uniform shape, sufficient strength, and constant ignition followed by stabilization and/or carbonization. The effects of the process-stabilization without carbonization and carbonizing temperatures - were also investigated from an environmental viewpoint, i.e., the conservation of energy. Only stabilization for 4 h or carbonization below 400 degrees C without stabilization yielded sufficient hardness; however, the faint odor of wood tar persisted. Stabilization followed by carbonization below 400 degrees C or stabilization for 20 h without carbonization completely eliminated the odor with increasing hardness. The heating value of the molded charcoal that was carbonized at 600 degrees C with or without stabilization was the highest, and its ignition temperature was also high. Despite a low heating value, the molded charcoal carbonized at 300 degrees C without stabilization was considered to be suitable for ignition due to its lowest ignition temperature of 233 degrees C. The molded charcoal, which was carbonized at 900 degrees C after stabilization, was activated by steaming for 60 min at 900 degrees C. The yield was 36 wt% and its surface area was 615 m(2)/g, which is rather moderate as compared with that of the activated carbons obtained from wood waste.