Competitive adsorption of phenolic compounds from aqueous solution using sludge‐based activated carbon

Abstract

Preparation of activated carbon from sewage sludge is a promising approach to produce cheap and efficient adsorbent for pollutants removal as well as to dispose of sewage sludge. The first objective of this study was to investigate the physical and chemical properties (BET surface area, ash and elemental content, surface functional groups by Boehm titration and weight loss by thermogravimetric analysis) of the sludge-based activated carbon (SBAC) so as to give a basic understanding of its structure and to compare to those of two commercial activated carbons, PICA S23 and F22. The second and main objective was to evaluate the performance of SBAC for single and competitive adsorption of four substituted phenols (p-nitrophenol, p-chlorophenol, p-hydroxy benzoic acid and phenol) from their aqueous solutions. The results indicated that, despite moderate micropore and mesopore surface areas, SBAC had remarkable adsorption capacity for phenols, though less than PICA carbons. Uptake of the phenolic compound was found to be dependent on both the porosity and surface chemistry of the carbons. Furthermore, the electronegativity and the hydrophobicity of the adsorbate have significant influence on the adsorption capacity. The Langmuir and Freundlich models were used for the mathematical description of the adsorption equilibrium for single-solute isotherms. Moreover, the Langmuir-Freundlich model gave satisfactory results for describing multicomponent system isotherms. The capacity of the studied activated carbons to adsorb phenols from a multi-solute system was in the following order: p-nitrophenol > p-chlorophenol > PHBA > phenol.

Activated carbon treatment of water extracts of Artemisia princeps pampanini to retain bioactive phenolic compounds and remove volatiles

“…Thus, adsorption of phenolic compounds on AC might be affected by the characteristic properties of phenolic polarity and stereospecific structure (29,30). AC is mainly hydrophobic and has a strong affinity for phenolic compounds with lower water solubility values (31). It was previously reported that hydrophobic compounds were adsorbed on AC to a greater extent than less hydrophobic compounds (32).…”

A comparison investigation on photocatalytic activity performance and adsorption efficiency for the removal of cationic dye: Quantum dots vs. magnetic nanoparticles

“…Schematic representation of possible mechanism of QDs based photodegradation of organic dyes. adsorbate molecules from the bulk liquid phase into the adsorbent surface is presumed to involve the following stages [60,61]:…”

Insights onto the Adsorption of MFe2O4 Nanoparticles Loaded onto Activated Carbon

“…Further decrease in pH, the quantity of undissociated phenol increases, this implies to the decrease in the interaction between phenol and the adsorbent. At a value of pH > 8, the PCP act as anions and this accompanies by a decrease in the adsorption between the negative charged phenoxy ion and the negative charge present on the surface of the adsorbent [24,25].…”