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Application of membrane techniques (pervaporation and membrane-based solvent extraction) and adsorption tothe removal of phenol from solutions modelling wastewater from phenol production by cumene oxidation processwas investigated. The transport and separation properties of composite membranes PEBA, PERVAP 1060 and PERVAP 1070 in pervaporation of water–phenol mixtures were determined. It was found that the best removal efficiency ofphenol was obtained using the PEBA membrane. MTBE, cumene and the mixture of hydrocarbons were applied inthe membrane-based phenol extraction. Extra-Flow contactor with Celgard X-30 polypropylene hollow-fiber porousmembranes was used in the experiments. MTBE was found the most efficient extractant. Adsorption of phenol on the different Amberlite resins was also investigated. Among the Amberlite resins of various grades used, the Amberlite XAD-4 had the best properties in the phenol removal from the aqueous solutions. It was shown that regeneration ofthe adsorbent bed could be effectively performed with sodium hydroxide solution.

Poly(ether block amide) membrane (PEBA) had the best separation properties in the pervaporative removal of phenol from water. Partial permeate fluxes of phenol through both PDMS membranes were practically the same. It means that the presence of zeolite filling of PERVAP– 1070 membrane did not influence the phenol transport. On the other hand flux of water was much smaller through the PDMS membrane with the zeolite filling (PERVAP–1070) compared to the pure PDMS membrane (PERVAP–1060). The results obtained in the solvent-based membrane extraction showed that extraction of phenol using MTBE gave the best results for this technique. However, one should remember that after extraction step it would be necessary either to return the mixture phenol–extraction solvent to the cumene oxidation process or to separate it and recycle the extraction solvent. For that reason, in the suggested hybrid system only membrane pervaporation followed by adsorption step was taken into account (Fig. 12). The best sorption properties were found in the case of the Amberlite XAD-4. Using this adsorbent, made of cross-linked styrene/divinylbenzene copolymer, the removal of phenol from model solution containing phenol (3–20 g/dm3) and sodium sulphate (30 g/dm3) was carried out by the column method. Non-combustible liquors: distilled water, sodium sulphate solution (30 g/dm3), eluate and sodium hydroxide solution (200 g/dm3) were used to regenerate the sorbent bed. It was found that the regeneration of the sorbent bed using NaOH solution enabled the most effective removal of phenol from the low concentrated solutions. Pervaporation and adsorption results obtained with water-phenol mixtures suggested that the hybrid system, schematically presented in Fig. 12, could be used to the efficient decontamination of the effluents from the cumene oxidation process.