in this research work, it was planned to study influences of hydrothermal treatment temperature, holding time and press temperature on wood density, spring back, moisture absorption as well as dimensional stability of combined-hydro-thermo-mechanically modified poplar wood. wood blocks were treated hydrothermally at temperatures 120, 150 and 180°c for holding time of 0, 30 and 90 min. afterward...

Chromated copper arsenate (CCA)-treated wood was liquefied with polyethylene glycol/glycerin and sulfuric acid. After liquefaction, most CCA metals (98% As, 92% Cr, and 83% Cu) were removed from liquefied CCA-treated wood by precipitation with calcium hydroxide. The original CCA-treated wood and liquefied CCA-treated wood sludge were fractionated by a modified Community Bureau of Reference (BCR...

B uilding outdoor structures such as decks, docks, and playgrounds often signifies the pursuit of a more healthful lifestyle, but the wood used in much of this construction poses potential environmental and health problems when these structures are demolished. The chemicals that preserve the wood, primarily the inorganic waterborne preservative chro-mated copper arsenate (CCA), are designed to ...

The wood preservative chromated copper arsenate (CCA) contains hexavalent chromium [Cr(VI)] and the conversion of Cr(VI) to trivalent chromium [Cr(III)] drives fixation of the treatment chemicals to the wood fibers. Since the toxicity of Cr depends on its valence state, an assessment of the Cr species occurring in CCA-treated wood, as well as leachates and ashes from CCA-treated wood, is helpfu...

hemicellulose of southern yellow pine wood spices was extracted by pressurized hot water at three different temperatures: 140°c, 155°c and 170°c. compounding with pp (polypropylene) was performed by extrusion after preparing wood flour and sieving to determine its mesh size. the ratio of wood to polymer was 50:50 based on oven-dry weight of wood flour. all extraction treatments and control samp...

Wood-inhabiting bacteria are associated with wood decay and may have an indirect influence on the decay process. Bacteria are able to affect wood permeability, attack wood structure, or work synergistically with other bacteria and soft-rot fungi to predispose wood to fungal attack. Bacteria that can inhabit chemically treated wood are recognized. The natural ability of certain bacterial genera ...

New alternative wood preservatives contain higher levels of copper (Cu) which can promote aquatic toxicity in natural water systems. Earlier work focused on evaluating toxicity using laboratory generated leaching solutions. In this study, the impact on preservative leaching and aquatic toxicity from treated wood products was evaluated using natural surface waters including waters from two river...

Chromated copper arsenate (CCA)-treated wood is a preservative treated wood construction product that grew in use in the 1970s for both residential and industrial applications. Although some countries have banned the use of the product for some applications, others have not, and the product continues to enter the waste stream from construction, demolition and remodeling projects. CCA-treated wo...

Several alternative methods for the disposal of chromated copper arsenate (CCA) treated wood waste have been studied in the literature, and these methods are reviewed and compared in this paper. Extraction experiments have been carried out on CCA treated wood and evaluated as a method to recover the metal compounds into either fresh wood preservatives or other useful industrial materials. Recyc...