Capture of dioxin derivatives on activated carbons: breakthrough curve modelling and isotherm parameters. (2016) - Tulaphol, Sarttrawut
Four dioxin derivatives (benzene, chlorobenzene, dichlorobenzene and o-chlorophenol) were individually adsorbed onto each of four types of activated carbon (AC) derived from different raw materials. The observed adsorption bed capacities were in the range of 0.916-0.99, with the AC derived from coconut shell (ACC) having the highest bed capacity of 0.99. The micropore size significantly affected the adsorption. The adsorption behaviour evaluation of ACC by thermal gravimetric analysis revealed that the highest activation energy for desorption belonged to o-chlorophenol (107 kJ/mol), followed by dichlorobenzene (102 kJ/mol), chlorobenzene (55 kJ/mol) and benzene (42 kJ/mol). Thus, chemisorption predominated over the interaction between ACC and dioxin derivatives. The ACC was then selected as the absorbent to model the breakthrough curves of the adsorption of the dioxin derivatives using the Aspen gas adsorption simulation program. Langmuir isotherm parameters were determined, and the simulation was found to provide a high adsorption performance compared to the experimental results in all cases.