Distillation: processes – separatory – Adding material to distilland except water or steam per se – Organic compound
Patent
1995-06-28
1997-07-15
Kim, Christopher
Distillation: processes, separatory
Adding material to distilland except water or steam per se
Organic compound
423338, 502233, B01D 334, C01B 3312
Patent
active
056479620
ABSTRACT:
The invention relates to modified SiO.sub.2 gels (xerogels), the preparation thereof and the use thereof as thermal insulators. The xerogels are prepared by acidifying an aqueous waterglass solution, polycondensing the silicic acid produced thereby, by adding a base, to an SiO.sub.2 gel, removing the water from the resulting gel by extractive distillation with an organic solvent which forms with water an azeotrope which separates on cooling into two phases, reacting the gel with a silylating agent, and then drying at pressures and temperatures which are below the critical pressure and/or the critical temperature of the organic solvent used for removing the water.
REFERENCES:
patent: 3801705 (1974-04-01), Krekeler et al.
patent: 3846537 (1974-11-01), Marotta
patent: 4042770 (1977-08-01), Bachl et al.
patent: 4190457 (1980-02-01), McDaniel
patent: 4382070 (1983-05-01), Novak et al.
patent: 4649037 (1987-03-01), Marsh et al.
patent: 4975405 (1990-12-01), Okamura et al.
patent: 5122291 (1992-06-01), Wolff et al.
patent: 5275796 (1994-01-01), Tillotson et al.
Chemisches Zentralblatt, No. 20, 1965, Berlin, pp. 87-90 by F. Polak et al.
Chemical Abstracts, vol. 81, No. 14, Oct. 7, 1974, Columbus, Ohio, Abstract No. 82740a by J. Viska et al.
Jansen Rolf-Michael
Zimmermann Andreas
Hoechst Aktiengesellschaft
Kim Christopher
LandOfFree
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