Preparation of capsules containing 1-nonanol for rapidly removing high concentration phenol from aqueous solution

This study investigated the potential of capsules containing 1-nonanol for the adsorption of phenol at high initial concentrations. The polysulfone capsules containing 1-nonanol (PSF@1-nonanol capsules) were successfully prepared with a phase inversion method, and the results showed that 1-nonanol was encapsulated with polysulfone as an encapsulation capacity of 67.99% was achieved. Systematic studies on phenol adsorption equilibrium, kinetics and isotherms by PSF@1-nonanol capsules were carried out. The results showed that the rate of adsorption of phenol is initially quite rapid and equilibrium is reached in about 90 min. Phenol adsorption uptake was found to increase with increase in initial concentration and adsorption time, whereas adsorption of phenol was more favourable at acidic pH and low temperature. The adsorption kinetics of phenol followed pseudo-second-order model, and the best fits of adsorption isotherms were achieved with the Freundlich equation. These results demonstrate that the use of PSF@1-nonanol capsules enhanced the mass transfer rate and the uptakes to phenol at high initial concentrations. Furthermore, after seven times of repeated extraction and stripping, the microcapsules kept almost the same adsorption ability, which indicated that the PSF@1-nonanol capsules have very good stability in the adsorption process. Therefore, PSF@1-nonanol capsules can be taken as an ideal adsorbent for rapid removal of high concentration phenol from aqueous solution.