Removal of Phenol and 4-Chlorophenol from Aqueous Solutions by Olive Stone-Based Activated Carbon

Abstract

ABSTRACT:The evaluation of agricultural by-products as a means of removing pollutants from contaminated wastewater is attracting increasing interest for sustainable development applications. The present work deals with the removal of phenol and 4-chlorophenol from aqueous solutions by chemically activated olive stones. The olive stones were soaked in 50% phosphoric acid for 3 h at 443 K. After washing, the product was activated in an inert atmosphere for 2 h or 3 h at temperatures within the range 873−1023 K. The carbons thus prepared were characterized by Methylene Blue and iodine adsorption, N 2 adsorption at 77 K in conjunction with the BET equation, scanning electron microscopy (SEM) and Boehm titrations. The sorption capacity towards both pollutants was determined by fitting the Langmuir model to the adsorption isotherms. The optimum activation temperature and time were 1023 K and 3 h, respectively. A maximum adsorption capacity of 189 mg/g was obtained for phenol and 436 mg/g for 4-chlorophenol. In comparison, the Merck and Aldrich commercial-grade powdered activated carbons ranked lower with adsorption capacities of 145 mg/g and 179 mg/g for phenol and 244 mg/g and 316 mg/g for 4-chorophenol, respectively.

Valorization of olive stones into a granular activated carbon for the removal of Methylene blue in batch and fixed bed modes

“…This ratio is slightly greater for the Organosorb 10 GAC suggesting that although the porosity was associated with a large part of microporous structure, the presence of carbon-oxygen groups may also have an influence on the adsorbate uptake by providing sites for additional adsorption. This may explain the slightly higher adsorption capacity exhibited by the commercial GAC [7].…”

“…On the other hand, adsorption has proved to be promising for the removal of organic molecules. Activated carbon has widely been used because of its high adsorption capacity of organic species [7,8]. Oil residue, natural coal and wood are known as the main precursors of activated carbons [9].…”

Adsorption of phenolic compounds on low-cost adsorbents: A review

“…The uptake of phenol was not affected by the presence of NaCl salt. Removal of phenol and 4-chlorophenol from aqueous solutions by chemically activated olive stones was studied [100]. The adsorption capacity was determined by fitting the Langmuir model to the adsorption isotherms.…”

Treatment of phenol and p-cresol in aqueous solution by adsorption using a carbonylated hypercrosslinked polymeric adsorbent

“…In addition, XAD-4 adsorbs phenol principally through van der Waals force due to its hydrophobic surface, while HJ-1 resin is modified with formaldehyde carbonyl groups on its matrix and its surface polarity is increased, the increased surface polarity will match the polarity of the adsorbates, enhancing the adsorption [27]. With regard to the comparison of phenol uptake as well as the required time from the beginning to the equilibrium onto HJ-1 resin with those of the activated carbon such as the acid treated [28], olive stone-based [29], and eucalyptus wood-based [30], the HJ-1 resin shows an excellent kinetic performance for phenol adsorption and the phenol uptake is acceptable. Taken into account the fact that the exhausted HJ-1 beads are amenable to regenerate for repeated used, HJ-1 resin can be taken as an ideal adsorbent for phenol removal from the contaminated water.…”