New synthetic route to Mg–Al–CO3 layered double hydroxide using magnesite

Abstract A novel synthesis of Mg–Al–CO 3 layered double hydroxide (LDH) through chemical precipitation and hydrothermal methods has been investigated in this paper. The advantages of this method are using magnesite as magnesium source and no CO 2 released in the process of preparation. Mg–Al–CO 3 LDH (ZY) prepared under the optimized condition (the molar ratio of magnesite and Al(NO 3 ) 3 ·9H 2 O was 2.5:1; the aging time and temperature were 16 h and 100 °C, respectively) was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), thermo-gravimetric and differential thermal analyser (TG–DTA) and scanning electron microscope (SEM). The crystal morphology of the prepared LDH displays platelet-like structure with a hexagonal shape, which is agreed with the LDH produced by industrial chemicals. Through elemental analysis and inductively coupled plasma-atomic emission spectrometry (ICP-AES), the chemical formula of ZY is determined as Mg 0.70 Al 0.30 (OH) 2 (CO 3 ) 0.15 ·0.6H 2 O.