Adsorption Equilibrium and Thermodynamics Behavior of Sodium Pentachlorophenol to Biomass-Derived Biochars at Two Pyrolytic Temperatures
Wheat straws were pyrolyzed at two temperatures (200 and 400°C). For two biochar, the Scanning electron microscope (SEM) and the BET surface area were analyzed. The thermodynamics of sodium pentachlorophenate adsorption on biochar were examined. Adsorption isotherm of sodium pentachlorophenate on biochar was determined and correlated with two well-known isotherm equations (Langmuir and Freundlich adsorption isotherm equation). The equilibrium data for sodium pentachlorophenate adsorption were fitted well with the Freundlich adsorption model. The thermodynamic parameters of Gibbs free energy (△Gθ), enthalpy (△Hθ), and entropy (△Sθ) were also calculated, and the positive value of △Hθ suggests the endothermic nature of the adsorption, whereas the negative values of △Gθ tend (s) to prove the spontaneous nature of the adsorption process.
Ji Zhao, Aijie Wang, Xinyong Li and Xiaoyi Wang
C. X. Zhang et al., "Adsorption Equilibrium and Thermodynamics Behavior of Sodium Pentachlorophenol to Biomass-Derived Biochars at Two Pyrolytic Temperatures", Advanced Materials Research, Vols. 955-959, pp. 2243-2247, 2014