Mathematical Modeling on Thermal Degradation of Wood Chips Using Glycerol and Alkaline Glycerol

Wood chips from poplar, beech and spruce wood samples were delignified by using glycerol as a solvent and alkaline glycerol with and without Na₂CO₃ and NaOH catalysts at different temperatures of 440, 450, 460, 470, 480, 490, and 500 K. Major byproducts from delignification processes of lignocellulosic biomass include lignin degradation products. Lignin and its degradation products have fuel values. The main importance of glycerol is not to be environment pollution and be a sulfur-free treatment. Since the glycerol is significant from ecological, economic, and technical points of view, these properties are important for manufacture technology, but the treatment time of process is slightly long. There was a good linear relation between the yield of deligfication (YD, wt%) and degradation temperature (T, K). For the wood samples, the regression equations from NaOH (10%) catalytic run for 0.3 mm × 15 mm × 15 mm chip size was:

For poplar wood: YD = 0.525T − 173.42(a)

For beech wood: YD = 0.491T − 163.01(b)

For spruce wood: YD = 0.234T − 84.13(c)

For Equations (a)-(c), square of the correlation coefficient (r²) were 0.9981, 0.9988, and 0.9997, respectively.