2. Materials and methods

carbolic acid. It's a white crystalline toxic solid with a sweet tarry odor commonly referred to as a "hospital smell"; with a pKa of 9.98 and solubility of 8% (wt.) in the water at 25°C. In fact, the US Environmental Protection Agency (EPA) and the European Union (EU) directive number 80/778/EC consider phenol as a priority pollutant [1]. The concentration of phenol in wastes varies in a wide range from several ppm to 2–3% and phenols degradability are limited. Several techniques are

Adsorption processes have been intensively used in wastewater treatment for phenol and other organic compounds. Phenols in olive mill wastewaters (OMWW)

Therefore, the necessity of the alternative adsorbents which are equally effective and easier to regenerate and recently, a new kind of hypercrosslinked polymeric adsorbent was found to be very effective for removing aromatic compounds from aqueous solutions [5, 7, 13, 14]. Macroreticular resins are the most promising in the separation processes due to its easier regeneration and it is well used in industrial practices. The wide variations in functionality, surface area, and porosity available for macroreticular resins present the possibility of its selective separation of the effective components. Furthermore, the regeneration of the resins can easily be accomplished with a solvent and hence, the adsorption of phenol can be realized by macroreticular resins. Numerous studies on the removal of metals and organic pollutants by these adsorbents in discontinuous systems have been reported [10, 11, 15]. However, the application in continuous systems i.e. in a fixed-bed column is often preferred, since it is simple to operate, given to high yields and can be scaledup in the laboratory process. In order to design and operate fixed-bed adsorption process successfully, both equilibrium and dynamic adsorptions in specified systems must be known. The indicators are the breakthrough curves under specified operating conditions must be predictable. The shape of this curve is determined by the shape of the isotherm equilibrium and it is influenced by the individual trans-

In this chapter, the experimental results on adsorption tests performed by resins were presented. The polyphenols are extracted from a nanofiltration concentrate stream produced during the purification of olive vegetation wastewater from a 3 phase process. This wastewater contains many polyphenols, mostly hydroxytyrosol,

The high organic content of olive wastewater exhibits to its impossible direct recovering of polyphenols content. The high suspended solids in the raw stream will quickly block the adsorption column, making the recovery process difficult. Moreover, many other interfering and undesired pollutants would interfere with the recovery process. For this reason, the recovery of polyphenols will be accomplished on a pretreated stream that is the concentrate of nanofiltration which is produced after the treatment of the raw wastewater by flocculation, photocatalysis and ultrafiltration. The concentrate of nanofiltration is rich enough of polyphenols to permit a suitable recovery from a technical and economical

have very complex compositions and the treatment feasibility has to be separately made through experimental approaches [2–6]. Conventional fixed bed processes involve a saturation, adsorption or loading step, followed by desorption, elution or regeneration steps [7]. The use of granular activated carbon (GAC) for removing toxic organic chemicals including phenol from wastewater is one of the best commercially proven methods. Although activated carbons exhibit an excellent adsorption capacity for the removal of phenol from wastewater, this method exhibited the difficulty to its regeneration and quite expensive to

available currently for the treatment of phenolic effluents.

port processes in the column of adsorbent [10, 11, 15].

which may have a market.

point of view.

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dispose of [7–12].

Sorption in 2020s
