Studies on the pyrolysis of chromated copper arsenate-treated wood: Analytical methodology and optimization

Low temperature pyrolysis offers a feasible option for wood waste management and the recovery of a variety of useful chemicals. The effect of Chromated Copper Arsenate (CCA) wood preservatives on the yield and composition of various pyrolysis products was investigated in the present research. A novel quantitative 31P NMR methodology has been developed to quantify levoglucosan and levoglucosenone from the pyrolysate of CCA-treated and untreated wood. The CCA treatment on wood had a significant effect on the amount of main carbohydrate derived degradation products of tar. In particular, a higher yield of levoglucosan can be obtained compared to that from untreated wood. Phosphoric acid has proven to be an efficient catalyst to favor levoglucosenone formation. The pyrolysis of CCA-treated wood in the presence of phosphoric acid gave rise to high yields of levoglucosenone, which demonstrated the potential for a new pathway in the rational use of CCA-treated wood waste. Pretreated wood with metal compounds has demonstrated that K2Cr2O 7 and CuSO4 salts promote the formation of levoglucosan. The CrO3 treatment was found to favor the formation of levoglucosenone. A kinetic study of the pyrolysis of CCA-treated wood by thermogravimetric analysis has shown that CCA components have a significant influence on the thermal decomposition behavior of CCA-treated wood, which accelerate the weight loss of wood and the oxidation of the char.