Removal of 2,4-dichlorophenol from aqueous solution by static-air-activated carbon fibers

Static-air-activated carbon fibers (ACFs) with lotus-root-like axially porous structure were used to adsorb 2,4-dichlorophenol (2,4-DCP) from aqueous solution. The adsorption isotherm was evaluated in the pH range 3.0–11.0. Results indicated that both Langmuir and Redlich–Peterson adsorption isotherms were appropriate for describing the adsorption characteristics of 2,4-DCP at various pH values and that lower pH values were favorable for adsorption. The adsorption of 2,4-DCP was controlled by the synergetic effects of π–ππ–π interaction and electrostatic attraction, and the former was dominant. Breakthrough curve results showed that the 2,4-DCP removal efficiency increased with an increase in the empty-bed contact time (EBCT). An EBCT of 0.660 min was sufficient for the adsorption of 2,4-DCP onto ACF, indicating a high adsorption rate. Desorption experiment results revealed that the ACF saturated with 2,4-DCP could be regenerated effectively by a 0.001 M NaOH solution.

More than 95% of 2,4-DCP was desorbed after the static-air-activated ACFs saturated by 2,4-DCP was were treated with 0.001 M NaOH for three times. The adsorption capacity of the regenerated ACFs for 2,4-DCP was of almost the same level as that of the initial ACFs. Effective application of the static-air-activated ACFs for 2,4-DCP adsorption could be realized readily.Figure optionsDownload as PowerPoint slide