R. Mezei et al., CHEMICAL PROCESSES INVOLVED IN THE SOL-GEL PREPARATION OF AN ALUMINUMOXOHYDROXIDE GEL FROM ALUMINUM NITRATE IN ORGANIC MEDIUM, Journal of materials chemistry (Print), 8(9), 1998, pp. 2095-2101
Hydrolysis of aluminium nitrate in propan-1-ol leads to an aluminium o
xohydroxide optically clear spinnable material as well as a slightly e
lastic, monolithic gel. The propanol has several roles in the hydrolys
is. It dissolves the Al nitrate, induces the decomposition of the nitr
ate ions through nitric acid and promotes the hydrolysis and condensat
ion of Al-III. Furthermore it reacts with nitric acid and/or its decom
position products resulting in formation of various oxidised derivativ
es of propan-1-ol. The products of the gel preparation, i.e. the organ
ic compounds formed during heating of the aluminium nitrate-propan-1-o
l mixture were investigated by gas chromatography as well as tandem MS
techniques and UV-VIS spectroscopy. The coordination sphere of Al-III
and the role of the organic compounds in building up the gel network
has been studied by Al-27 MAS NMR and IR spectroscopy.