Artículos de revistas
N-alkylmonoamine Into Crystalline Lamellar Titanium Phenylphosphonate. Intercalation Enthalpies, Gibbs Free Energies And Entropies
Registro en:
Journal Of Thermal Analysis And Calorimetry. , v. 71, n. 2, p. 459 - 465, 2003.
13886150
2-s2.0-0037289212
Autor
Ruiz V.S.O.
Airoldi C.
Institución
Resumen
Crystalline lamellar titanium phenylphosphonate was intercalated with H-alkylmonoamines, H3C(CH2)n-NH2 (n=0 to 3), which decomposed on heating in four distinct stages. The lamellar compound was calorimetrically titrated with ethanolic amine solution at 298.15±0.02 K and the enthalpy, Gibbs free energy and entropy were calculated. With the exception of butylamine, the enthalpic values increased with the number of carbon atoms in the amine chain, as -16.20±0.22; -18.70±0.19; -23.70±0.24 and -18.30±0.22 kJ mol-1, from n=0 to 3. The exothermic enthalpic values reflected a favorable energetic process of intercalation, when the solvated ethanol molecules on inorganic matrix are progressively substituted by solute. The negative Gibbs free energy results supported the spontaneity of the reactions and the positive favorable entropic values are in agreement with the increase of solvent molecules in the reaction medium, as the amine becomes bonded to the crystalline lamellar inorganic matrix. 71 2 459 465 Anillo, A.A., García, M.A.V., Llavona, R., Suárez, M., Rodríguez, J., (1999) Mater. Res. Bull., 34, p. 627 Clearfield, A., (1998) Progr. Inorg. Chem., 47, p. 371 Zhang, B., Poojary, D.M., Clearfield, A., (1996) Chem. Mater., 8, p. 1333 Cabeza, A., Aranda, M.A.G., Lara, M.M., Bruque, S., Sanz, J., (1996) Acta Cryst., B52, p. 982 Hix, G.B., Harris, K.D.M., (1998) J. Mater. Chem., 8, p. 579 García, M.A.V., Jaimez, E., Bortun, A., García, J.R., Rodrígues, J., (1995) J. Porous Mat., 2, p. 85 Nunes, L.M., Airoldi, C., (1999) Chem. Mater., 11, p. 2069 Nunes, L.M., Airoldi, C., (2000) J. Solid State Chem., 154, p. 557 Fonseca, M.G., Airoldi, C., (2001) J. Therm. Anal. Cal., 64, p. 273 Zhang, Y., Scott, K.J., Clearfield, A., (1995) J. Mater. Chem., 5, p. 315 Fredoueil, F., Massiot, D., Janvier, P., Gingl, F., Doeuff, M.B., Evain, Clearfield, A., Bujoli, B., (1999) Inorg. Chem., 38, p. 1831 Poojary, D.M., Clearfield, A., (1995) J. Am. Chem. Soc., 117, p. 11278 Morizzi, J., Hobday, M., Rix, C., (2000) J. Mater. Chem., 10, p. 1693 Zhang, Y., Scott, K.J., Clearfield, A., (1995) J. Mater. Chem., 5, p. 315 Arújo, A.S., Medeiros, D.S., (1997) An. Assoc. Bras. Quim., 46, p. 50 Lima, C.B.A., Airoldi, C., (2001) Int. J. Inorg. Mater., 3, p. 907 Santos, M.R.M.C., Airoldi, C., (1996) J. Colloid Interface Sci., 183, p. 416 Arakaki, L.N.H., Nunes, L.M., Simoni, J.A., Airoldi, C., (2000) J. Colloid Interface Sci., 228, p. 46