Liquid Phase Synthesis And Characterization Of Layered Titanates And Layered Polysiloxane And Saccharin Column To Support The Study Of Layered Double Hydroxides

Layered materials have been of scientific and technological interest in many fields such as catalysis, medicine, sorption, separation and conduction etc since these materials exhibit some unique properties. The design, synthesis and study of novel intercalated layered materials are our main goal. In addition, the development of novel and simple synthesis method is also a significant topic that involves in intercalation chemistry.In this work, we review the recent progress in relevant directions. A series of intercalated layered materials were prepared, and their structures were characterized by means of XRD, FT-IR, UV-VIS etc. The main results are summarized as follows:(1) Preparation and characterization of tetrabutylammonium-intercalated layered titanate by liquid-phase techniqueTetrabutylammonium-intercalated layered titanates were successfully prepared by the reaction between tetrabutyl titanate and tetrabutylammonium hydroxide based on an acid-base reaction. The effects of the concentration of tetrabutyl titanate ([Ti]), molar ratio of tetrabutylammonium hydroxide to tetrabutyl titanate (R), reaction time (t), pH value and reaction temperature (7) on the structures of the products were investigated in detail. The results indicated that the product obtained under the conditions: [Ti] = 0.5 mol·L^-1, R = 0.5, pH = 7, T= 50℃, and t = 6 h exhibited a good crystallinity.(2) Preparation and characterization of layered polysiloxaneThe two-dimensional layered polysiloxane containing alkylammonium groups was synthesized by a sol-gel reaction of 3-aminopropyltriethoxysilane catalyzed by hydrochloric acid. The influence of the molar ratio of HCl to APS (R), pH value, reaction temperature and reaction time was investigated, and the optimum reaction condition was found. The interaction between the host layers and the intercalated gust anions belongs to electrostatic mode. Further, the layered polysiloxane was reacted with dodecyl sulfate, and the resultant product exhibited a mesoporous structure. The product calcined at 450℃in air exhibited a narrow BJH pore size distribution centered at 2.68 nm, and BET specific surface area of this product was 718 m²/g.(3) Preparation and characterization of pillared layered double hydroxidesThe Zn-Al and Mg-Al layered double hydroxides (denoted as Zn₂Al-NO₃-LDHs and Mg₂Al-NO₃-LDHs) were synthesized. It was found that the C₇H₄O₃SN^- (anions of saccharin) could be easily intercalated into the interlayers of Zn₂Al-NO₃-LDHs by ion-exchange way. XRD result indicated that the intercalated product had a good crystallinity. The possible structure mode was suggested based on the molecular structure of saccharin, and the intercalation mode between host layers and guest anions.