Adopting homogeneous precipitation method,nano-NH4AlO(OH)HCO3 precursor was prepared using NH4Al(SO4)2 and NH4HCO3 as the starting materials. Effects of mixing mode on preparing precursors were identified by XRD,TEM.
Synthesis of High Active Submicron Magnesium Oxide Ultrafines in Mother Bittern after Extracting K_2SO_4 (Ⅰ) - Preperationof Precursor Compound [xMg(OH)_2·yMgCO_3·nH_2O] by Homogeneous Precipitation Method
In this paper, the influences of several different Ti precursors on the product were studied. It was concluded that only when the precursor is TiCl4 and the sintering temperature is 360℃ and the duration is 8 hours, the pure Ba2Ti9O20 phase with high crystallinity can be obtained.
The overall process involves three steps: preparation of insoluble carboxyl-containing grafted starch copolymer (ISC), formation of precursor (ISC-Co), decomposition of ISC-Co, and phase transition of Co3O4 nanoparticles.
The precursor was proved to be [Zn5(OH)6(CO3)2] by TG-DTG-DTA and IR analysis.
This precursor was calcined at 300°C for 1, 2 and 3 hours respectively, and then the nanocrystalline ZnO of different grain size were obtained.
Steam produced during the decomposition process accelerated the sintering of MgO, and MgO with surface area as high as 412 m2 · g-1 was obtained through calcining its precursor in flowing dry nitrogen at 520°C for 4 h.
ZrWMoO8 powders with different morphologies were obtained using ammonium tungstate, molybdate tungstate and zirconium tungstate as the starting materials by dehydrating the precursor ZrWMoO7(OH)2(H2O)2.