Novel technology of supercritical drying for nano-porous materials;

Use of anhydrous ethanol as solvent to prepare nano A1_2O_3 by a supercritical drying method;

Using incipient impregnation,sol-gel method and conventional drying,and sol-gel and supercritical drying techniques,three kinds of 20% Ni/Al2O3 catalysts have been prepared,the catalyst samples were characterized by means of BET,XRD,H2-TPR and H2-TPD.

And at the same time,the developments of such techniques as supercritical fluid drying,azeotropic distillation,vacuum freeze drying ,microwave drying,used for the drying of nanometer particles are reviewed.

Nanosized TiO 2-ZnO (7～10 nm) composite catalyst was prepared from TiCl 4 an d Zn(NO 3) 2·6H 2O by sol-gel and supercritical fluid drying (SCFD) methods .

The nano - sized MgO - Al2O3 binary aerogel was synthesized by sol - gel supercritical fluid drying technology using Al(NO3)3 and Mg(NO3)2 as the starting materials.

On the basis of knowledge of these influencing factors,the shrinkage cracking problems can be solved by control of microstructure of silica aerogels and ethanol super critical drying.

Silica aerogels were prepared from TEOS through the sol gel process and super critical drying technique.

Nano-porous material SiO2 aerogels were prepared from TEOS through sol-gel process and super critical drying technique.

Alumina aerogels of light nano mesoporous solid material are prepared from Al,n-butanol and ethyl acetoacetate by the sol-gel rute and the N_2 supercritical drying technique.

Silica aerogels were prepared through a two-step catalyzed sol-gel route and ethanol supercritical drying technique.

The preparation and characterization of superfine alumina particles were studied by sol-gel and supercritical drying method, transmission electron microscope(TEM) and BET techniques.

It was studied that the effect of supercritical drying (SCD) on the structure and activity of Mn-substituted hexaaluminate catalyst (LaMnAl 11O 19) for methane combustion.