Efficient removal of pentachlorophenol from wastewater by novel hydrophobically modified thermo-sensitive hydrogels

Poly ( N -isopropyl acrylamide- co -butyl acrylate) (PNIPAM-BA) hydrogels were synthesized by copolymerization of N -isopropyl acrylamide (NIPAM) with butyl acrylate (BA), which have been proposed as adsorbents for the efficient removal of hydrophobic organic pollutants , e.g . pentachlorophenol (PCP). Adsorption experiments showed high removal efficiencies of PCP. The isotherm experimental data of PCP fitted Langmuir model, and the adsorption capacity of PNIPAM-11% BA hydrogel was greater than that of the original PNIPAM hydrogel. It is possibly due to the enhanced interaction between the hydrophobically modified hydrogels and PCP. Moreover, the PNIPAM-BA hydrogels could be easily recycled by the desorption process at 323   K in solution.