Sorption of Cu(II) onto silica gel immobilized calix[4]arene derivative with tripodal structure

This study contains the synthesis of silica gel-immobilized calix[4]arene derivative (TR-CL[4]P) as a new sorbent and its sorption studies towards Cu (II) ion in aqueous solution. The aldehyde pointed calix[4]arene derivative 5 was synthesized and then it was immobilized onto 3-aminopropilsilica gel (APS). In batch sorption experiments, the experimental results showed that TR-CL[4]P is effective sorbent towards Cu (II) ion. Therefore, the effect of solution pH, sorption time, temperature and initial metal ion concentration onto Cu (II) sorption was investigated. Maximum Cu(II) removal was obtained at 30 A degrees C, 30 min and pH 6.0 for TR-CL[4]P and the batch sorption capacity was found as 17.8 mg/g. The characteristics of the sorption process for Cu (II) ion were evaluated by using the Langmuir, Freundlich and Dubinin-Radushkevich (D-R) adsorption isotherms. Also, thermodynamic parameters, i.e., Delta G, Delta S, and Delta H were calculated for the system.