The removal of chlorophenols from aqueous solutions using activated carbon adsorption integrated with H2O2 oxidation

Abstract

The removal of eight chlorophenols (2-CP, 3-CP, 4-CP, 2,3-DCP, 2,4-DCP, 2,5-DCP, 2,6-DCP and 2,4,6-TCP) using adsorption on activated carbon and adsorption in the presence of hydrogen peroxide was investigated. The influence of the pH, activated carbon dosage and hydrogen peroxide concentration were studied. The effects of the chlorine atom position and the chlorine content in the chlorophenol molecules on their degradation were also studied. The results revealed that the integration of the activated carbon and H 2 O 2 treatment was more effective for the removal of the chlorophenols than using the activated carbon alone. The adsorption kinetics and adsorption efficiency increased with the increasing substitution of chlorine on the aromatic ring. The degradation rate and degradation efficiency of the chlorophenols using the activated carbon integrated with H 2 O 2 decreased with the increasing chlorine atoms in the molecule. The combination of the activated carbon with hydrogen peroxide may significantly enhance the process and could offer an interesting alternative in wastewater treatment.

Adsorption Properties of Activated Tire Pyrolysis Chars for Phenol and Chlorophenols

“…This suggests that the adsorption of phenols on the ATPCs and CB-V follows the pseudo-second-order kinetic model and chemical adsorption might be the rate-limiting step involving valency forces through sharing or exchange of electrons between adsorbent surface and adsorbate molecules [20]. The similar phe- nomena in the adsorption of phenolic compounds have also been observed by other authors [21][22][23][24][25][26][27]. All of the adsorbates were adsorbed faster on CB-V carbon black than on ATPCs.…”

“…Rincon-Silva et al [23] as well as Strachowski and Bystrzejewski [24] found that 4CP was adsorbed faster than Ph onto lignocellulose-derived activated carbon and carbon nanotubes, respectively. Garba and Rahim [25] reported that DCP was adsorbed faster than 4CP on the activated carbon prepared from an agricultural waste, while Kuśmierek [27] observed the same regularity on the Ceca L2S-powdered activated carbon. Fig.…”

“…For all four adsorbents, the adsorption capacities followed the order of Ph < 4CP < DCP. Numerous papers [22,27,28,35,[37][38][39] reported that the adsorption of phenolic compounds increases with a respective increase in their molecular weight and size and a decrease in their water solubility. The results obtained in these studies are in agreement with the literature data.…”

Synthesis of ZnO photocatalyst modified with activated carbon for a perfect degradation of ciprofloxacin and its secondary pollutants

“…Moreover, AC is able to activate hydrogen peroxide, producing reactive free radicals as the oxidizing agents of organic pollutants: …”

Adsorption of 4-Chlorophenol from Aqueous Solution Onto Iraqi Bauxite and Surfactant–Modified Iraqi Bauxite: Equilibrium, Kinetic, and Thermodynamic Studies

“…They can find their way to the environment since they were detected at high concentrations in wastewater treatment plant (WWTP) and discharged effluents close to industrial activities 3 . Due to the toxicity and carcinogenic properties, the long term exposure to chlorophenols at high concentration levels was found to cause liver, kidney and neurological defects, and therefore, their removal from water sources becomes environmentally warranted 4,5 . There are different physical and chemical technologies currently used for removal phenol and its derivative compounds from their aqueous solution like oxidation 6 , adsorption 7 and ion exchange 8 .…”