Impact of Birch Wood Prehydrolysis Conditions upon the Yield and Properties of Activated CarbonfFrom Lignocellulose

Abstract

The xylan-rich outer layer of birch veneer blocks making plywood factory residue veneer shorts is an ideal raw material for production of furfural, acetic acid and activated carbon. The aim of our investigation was to find optimum prehydrolysis conditions, within the limits of technological parameters tested at present, and to secure high yield and quality of all intended products. It has been elucidated that a 2% catalyst (H2SO4) concentration at 167–177oC ensures high yield of furfural and the quality of lignocellulose is appropriate for processing into activated carbon. During prehydrolysis, the plasticity of lignocellulose is greatly improved, and it granulates perfectly. The activated carbon yield in comparable conditions is by 10–15% higher; the sorption activity of iodine is practically the same (907 and 953 mg I2/g, respectively) as in the case of the catalyst concentration 3% (o.d. wood basis) even not taking into account the 13% lower activated carbon yield at a 3% catalyst concentration. The superheated steam expenditure is lower, since partly it can be substituted by carbon dioxide