Hydrotalcite as a Potential Sorbent for the Removal of 2,4-Dichlorophenol.

The removal of 2,4-dichlorophenol (DCP) using calcined and modified forms of hydrotalcite (HT) was studied. HT was calcined at 550 ° C for 3 h. The calcined form (HTC) was modified under argon atmosphere using sodium stearate in an amount equivalent to 100% of the theoretical anion exchange capacity of HT. The 3 forms of HT were subjected to X-ray diffraction analysis. It was determined that the peak with characteristic basal spacing d = 7.62 Å corresponding to interlayer carbonate anion disappeared in HTC and a peak with d = 32 Å confirming the adsorption of stearate anion appeared in organo-HT. Adsorption equilibria of DCP on HT and organo-HT were measured using batch equilibration. Adsorption behavior was modeled by the modified Freundlich equation. It was determined that HTC and organo-HT have maximum efficiencies corresponding to certain initial concentrations, i.e. 2.76 mmol/l for HTC and 3.68 mmol/l for organo-HT. At these concentrations, HTC and organo-HT can adsorb 61% and 17% of DCP, respectively. [ABSTRACT FROM AUTHOR]