Removal of phenol from aqueous solution using commercial strong base anion exchange resin AmberliteTMPWA5

Phenol and phenolic compounds are widely used in modern economies, for, among others, for the production of dyes and pigments, medicines, plant protection products or materials like phenol-formaldehyde resins. Phenols are components of crude oil, therefore thus they are present in petroleum industry processes and commonly appear in aquatic ecosystems as a result of industrial wastewater leakage. Due to its toxicity, phenol is classified as a priority pollutant, therefore its removal from the water environment is very important. Ion exchange resins are increasingly widely used in water purification systems. Therefore, this work presents the first experimental study of phenol removal using an anion exchange resin, namely AmberliteTM PWA5. Phenol detection in a water solution was carried out by means of ultraviolet spectroscopy (absorbance at 287 nm). The influence of contact time on the sorption process of phenol on PWA5 resin was investigated at three different pH values of aqueous solution (4, 7 and 11). Next, sorption experiments using PWA5 resin were tested at pH 11. In that condition predominantly the ion exchange between the triethylammonium group of the resin and phenol compound which occurs in anionic form take place. Infrared spectroscopy measurements and thermochemical parameter estimation brought closer the essence of the phenol removal process using PWA5 resin. The fit of the Freundlich and Langmuir isotherm models to the experimental results was in good agreement (R2=0.948-0.967). The maximum sorption capacity of the phenol solution in demineralized water was 237.3 mg/g, for a solution with an ionic strength of 0.01 M was 227.3 mg/g (for phenol concentrations in the range of 2.5-5000 mg/L). Additional experiments confirmed the high efficiency of phenol desorption from PWA5 resin using various regenerants. This proves that PWA5 resin has good properties for removing phenol from aqueous solution.