Kinetics and Thermodynamic Analysis of Recent and Ancient Buried Phoebe zhennan Wood

Abstract

Kinetics and thermogravimetric analysis of recent Phoebe zhennan wood (RZ) and ancient buried P. zhennan wood (ABZ) were investigated under a nitrogen atmosphere at different heating rates of 5, 10, 15, and 20 K/min. The activation energy values were estimated based on the Flynn–Wall–Ozawa model-free method, and then, the Coats–Redfern model-fitting method was used to predict the reaction mechanism. The best model of RZ for regions 1 and 2 was based on the diffusional and reaction order (second-order) mechanism, respectively, while a diffusional (Jander equation) mechanism is the best model for ABZ. The change in enthalpy and activation energy of the RZ was lower than that of the ABZ at different conversion rates. When the conversion rate was less than 0.4, the RZ may require lower thermal decomposition reaction energy, but the overall energy of thermal decomposition reactions and the degree of disorder was not much different.

Efficient and Easily Recyclable Catalyst for the Alkylation Reaction of Phenol and tert-Butyl Alcohol

“…The linearized Eyring equation based on transition state theory was employed to calculate the enthalpy of activation Δ H * and the entropy of activation Δ S *, and the equation was expressed as − where κ is the transmission factor (we assumed that the value is 1), h is the Planck’s constant, which is equal to 6.626 × 10 –34 J/s –1 , and k b is the Boltzmann’s constant, which is equal to 1.381 × 10 –23 J/K.…”