| A serials of organic-inorganic hybrid have been successfully assembled by the intercalation of the chiral organic supermolecular compounds into layered double hydroxides (LDHs). The intercalation of (+)-Dibenzoyl-D-tartaric acid (DBTA, guest) and D-(+)-di(p-toluoyl) tartaric acid (DTTA, guest) into three kinds of LDHs had been investigated by the ion exchange method. The adsorption of phenylalanine (Phe) from aqueous solution on CuZnAl-CO3-calcined layered double hydroxides (CLDH) was also investigated.(1) The intercalation of (+)-Dibenzoyl-D-tartaric acid (DBTA) into Mg-Al layered double hydroxide (LDH-CO3, LDH-NO3) by ion exchange method has been investigated. The samples thus obtained were characterized by X-ray powder diffraction (XRD), Infrared (FT-IR), Thermogravimetric analyses (TG-DSC), Element chemical analyses (EA) and Inductively coupled plasma spectrometry (ICP). After the intercalation of DBTA, the gallery heights are range between 1.98 and 2.08nm. The decomposing temperature of DBTA-LDHs increase. The formulas of DBTA-LDH areMg0.67Al0.33(OH)2[D-(+)C18H10O8]0.105(CO3)0.06·1.043H2O,Mg0.717Al0.283(OH)2[D-(+)C18H10O8]0.114(NO3)0.02·0.75H2O.(2) A large anionic (+)-2,3-di(p-toluyl)-tartaric acid (DTTA) has been intercalated into three kinds of layered double hydroxides (LDHs: MgAl-CO3-LDH, ZnAl-CO3-LDH, ZnAl-NO3-LDH) host by the ion-exchange method with a solution of DTTA, in ethanol. The samples have been characterized by XRD, FTIR, EA, ICP and DSC-TG. After the intercalation of DTTA, the gallery height range between 1.32 and 1.60nm. Infrared spectra and DSC-TG curves reveal the presence of a complex system of supramolecular host-guest interaction and the thermal stability of materials increase. The decomposing temperature of DBTA-LDHs increased to463-586℃. According to the TG, EA and ICP, the formulas of DTTA-LDHs are Zn0.678Al0.337(OH)2[D-(+)-C20H16O8]0.160(CO3)0.04·1.039H2O,Zn0.682Al0.338(OH)2[D-(+)-C20H16O8]0.122(CO3)0.03·0.617H2O,Zn0.668Al0.323(OH)2[D-(+)-C20H16O8]0.112(NO3)0.02·0.700H2O;(3) CuZnAl-CO3-LDH with a Cu/Zn atomic ratio of 5:1 and a (Cu+ Zn)/Al ratio of nearly 2) was prepared and its calcined product (CLDH) was obtained by heating CuZnAl-LDH at 500℃. Bath sorption studies were conducted to investigate removal of phenylalanine (Phe) from aqueous solution by CLDH. The results show that CLDH can be used as an effective absorbent for the removal of Phe from aqueous solution and its sorption capacity was higher than that of Mg-Al-CO3-CLDH. The absorption processes are followed the Lagergren's first order kinetic model. The absorption data are fitted well with the Langmuir isotherm equation. The thermodynamic parametersΔG0,ΔH0 andΔS0 were calculated to predict the nature of adsorption. The negative and positive values ofΔG0 andΔH0 indicate that the adsorption process is spontaneous and endothermic in nature, respectively. |
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