Layered Crystalline Barium Phosphate Organofunctionalized for Cation Removal

The available hydroxide groups inside the lamellar cavity of barium phosphate (BaP) were reacted with the silyating agents (RO) 3 Si(CH 2 ) 3 L x (L 1 = NH 2, L 2 = NH(CH 2 ) 2 NH 2, and L 3 = NH(CH 2 ) 2 NH(CH 2 ) 2 NH 2 ), to yield organofunctionalized nanomaterials BaPSiL 1, BaPSiL 2, and BaPSiL 3 . The amount of organofunctional groups covalently attached to the inorganic layer was 1.24, 1.46, and 1.23 mmol g - 1, respectively. The basic nitrogen center atoms attached to the pendant organic chains adsorb FeCl 3, CuCl 2, and ZnCl 2 from ethanol solutions to give well-established isotherms at 298 ± 1 K. The results obtained in flow experiments showed a retention and recovery of ca. 100% of the metal ion with packed BaPSiL x columns from solution containing a mixture of these cations. The energetic effect caused by iron, copper, and zinc ion interactions was determined through calorimetric titration at the solid−liquid interface and gave a net thermal effect that enabled the calculation of the exothermic enthalpic values and the equilibrium constants. The complete thermodynamic data showed that the system has favorable enthalpic, Gibbs free energy, and entropic values. The cation removal properties were used with packed columns to successfully determine these cations in ethanol used as fuel sources.