Efficient phenol removal of wastewater from phenolic resin plants using crosslinked cyclodextrin particles

Removal of phenolic compounds from a raw industrial wastewater from phenolic resin processing, of which the components are phenol (8.9 wt%), m‐ and p‐cresols (0.33 wt%), and xylenols (0.044 wt%), was carried out by using crosslinked cyclodextrin particles as a sorbent. A series of sorbents was prepared by varying the combination of cyclodextrin (CyD), β‐CyD, γ‐CyD, Mix‐CyD (α‐CyD:β‐CyD:γ‐CyD:dextrin = 30:10:10:50 wt/wt), the crosslinker, hexamethylene diisocyanate (HDI) or toluene‐2,6‐diisocyanate, and their molar ratio in the reaction batch. The removal of the phenolic compounds from raw industrial wastewater was an instantaneous process and was completed within about 5 min. The best removal efficiency was obtained by the crosslinked β‐CyD with HDI in a 1:8 molar ratio or the crosslinked Mix‐CyD with HDI, also in a 1:8 molar ratio. The prepared sorbents were efficiently regenerated by elution of the adsorbed phenols from the crosslinked polymers with methanol. Copyright © 2006 Society of Chemical Industry