Removal of p-nitrophenol by a water-compatible hypercrosslinked resin functionalized with formaldehyde carbonyl groups and XAD-4 in aqueous solution: A comparative study

J Colloid Interface Sci. 2009 Apr 1;332(1):60-4. doi: 10.1016/j.jcis.2008.12.039. Epub 2008 Dec 24.

Abstract

Chloromethylated styrene-divinylbenzene copolymers were post-crosslinked through Fredel-Crafts alkylation reaction and a water-compatible hypercrosslinked resin HJ-1 was developed successfully. It can be wetted directly by water and can be used without any wetting process. It was applied to remove p-nitrophenol in aqueous solution in comparison with the commercial Amberlite XAD-4 resin. Their adsorption behaviors for p-nitrophenol were conducted and it was found the adsorption dynamics obeyed the pseudo-second-order rate equation and the intra-particle diffusion was the rate-limiting step. The adsorption isotherms can be correlated to Freundlich isotherm and the adsorption capacity onto HJ-1 resin was much larger than XAD-4. The maximum adsorption capacity of p-nitrophenol for HJ-1 resin was measured to be 179.4 mg/g with the equilibrium concentration at 178.9 mg/l and the maximum removal percentage was predicted to be 98.3%. The adsorption thermodynamic parameters were calculated and the adsorption was mainly driven by enthalpy change. The micropore structure, the size matching between the pore diameter of HJ-1 resin and the molecular size of p-nitrophenol, and polarity matching between the formaldehyde carbonyl groups of HJ-1 resin and p-nitrophenol bring the larger adsorption capacity and higher adsorption affinity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adsorption
  • Bentonite / chemistry*
  • Entropy
  • Hydrogen-Ion Concentration
  • Methylene Blue / chemistry*
  • Water Pollutants, Chemical / chemistry*
  • Water Purification / methods*

Substances

  • Water Pollutants, Chemical
  • Bentonite
  • Methylene Blue