Adsorption Equilibria of L-(+)-Tartaric Acid onto Alumina

Abstract

The adsorption equilibria of L-(+)-tartaric acid onto alumina from wastewaters of wineries were studied, and it has been found that the equilibrium adsorption fits the Langmuir and Freundlich isotherms. Adsorption experiments were carried out at three different temperatures (298, 310, and 325) K. The adsorption Of L-(+)tartaric acid is dependent on the acid concentration and the amount of alumina. The maximum percentage removal of L-(+)-tartaric acid was 22 % by alumina at 298 K. The Langmuir and Freundlich constants have been found to be 0.023 g.g(-1) and 0.014 (g.g(-1))/(L.g(-1))(-1/n), respectively, at 298 K. The thermodynamic parameters Delta H(ads)(0) and Delta S(ads)(0) for the adsorption of tartaric acid on alumina have been calculated to be -5.62 kJ.mol(-1) and 50.65 J.mol(-1).K(-1), respectively.