A novel gas-liquid contacting route for the synthesis of layered double hydroxides by decomposition of ammonium carbonate

作者：Lei XD; Yang L; Zhang FZ; Duan X^*

来源：Chemical Engineering Science, 2006, 61(8): 2730-2735.

DOI：10.1016/j.ces.2005.11.053

• layered double hydroxide
• hydrotalcite
• ammonium carbonate
• pH gradient
• gas-liquid contacting

Layered double hydroxides (LDHs) carbonate with the M2+/Al3+ (M = Mg or Zn) molar ratio of 2/1 has been synthesized by a gas-liquid contacting route with the decomposition of ammonium carbonate. The key feature of this method is a pH gradient germinated by the diffusion of NH3 and CO2 vapors in the metal salts solutions from solid (NH4)(2)CO3 in a closed environment. The physicochemical properties of these two particles were characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, simultaneous thermogravi metric and differential thermal analysis (TG-DTA), scanning electron micrograph (SEM) or transmission electron micrograph (TEM), laser particle size analysis and low-temperature N-2 adsorption-desorption analysis. The results manifested that these two particles obtained by the method present well-crystalline, uniform crystallite size and relatively high surface area. The particle sizes of MgAl-LDH and ZnAl-LDH are around 0.55 and 0.069 mu m, respectively. Both the BET surface areas of them are about 100 m(2)/g.

• 出版日期2006-4
• 单位北京化工大学