Sorption of remazol brilliant blue R onto polyurethane-type foam prepared from peanut shell

The powders of peanut shell is first liquefied with the mixture of polyethylene glycol-400 and monoethylene glycol (MEG) using sulfuric acid at 160 degrees C for 2 h. Polyurethane (PU)-type rigid foam is prepared from the reaction between peanut shell liquefied with the MEG and diphenylmethane diisocyanate. Then the PU foam is used as a sorbent for the removal of the remazol brilliant blue R from aqueous solution. The sorption of the dye increases with increasing initial concentration, temperature, and ionic strength, while decreasing with increasing pH. From the isotherm and kinetic studies, it is seen that the sorption process is in the best agreement with the Langmuir isotherm and the pseudo second-order kinetic model. Desorption and FTIR studies show that a chemisorption process occurs between dye and foam, probably indicating electrostatic interactions. The thermodynamic parameters (i.e., standard free energy, standard enthalpy, and standard entropy) are determined, and the results obtained are discussed in detail. (c) 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci, 2013