Synthesis of highly crystalline Al-Li layered double hydroxide by homogeneous precipitation method

Citation
E. Narita et al., Synthesis of highly crystalline Al-Li layered double hydroxide by homogeneous precipitation method, NIP KAG KAI, (5), 2001, pp. 273-279
Citations number
19
Language
CHINESE
art.tipo
Article
Categorie Soggetti
Chemistry
Journal title
NIPPON KAGAKU KAISHI
ISSN journal
0369-4577 → ACNP
Issue
5
Year of publication
2001
Pages
273 - 279
Database
ISI
SICI code
0369-4577(200105):5<273:SOHCAL>2.0.ZU;2-Y
Abstract
The formation of Al-Li layered double hydroxide(LDH) by a homogeneous preci pitation method using urea as a precipitant has been investigated as a func tion of solution composition, aging temperature and time. When the mixed aq ueous solution of Al(NO3)(3) and LiNO3 containing urea was heated, the solu tion pH was gradually increased with the thermal hydrolysis of urea and a w hite precipitate began to form at pH 5.7-6.1 in the temperature range of 80 -90 degreesC. The crystallinity of the solid products was found to be influ enced by the reaction conditions. A quite highly crystallined Al-Li LDH, with a basal spacing of 7.83 Angstro m, was obtained from the mixed solution of Al/Li molar ratio of less than 0 .10 (0.166 mol dm(-3) Li+) and urea concentration of more than 1.0 mol dm(- 3) at above 85 degreesC for 3-5 h. The typical LDH product has a chemical c omposition of Al2.17Li1.00 (OH)(6.83)(CO3)(0.34). gammaH(2)O and is an aggr egate of hexagonal plate-like shape particle with later al dimensions of ab out 2 mum From the analytical results of the solid products obtained during the aging, it was found that amorphous aluminium hydroxide was precipitate d first and then LDH was gradually crystallized by the reaction of the alum inium hydroxide precipitate with Lit ion in the solution.