Method of preparing a controlled pore volume alumina with citric acid
CA 1069486 A · Owner: Nalco Chemical Company · Inventors: Choca, Monica E.; Broersma, Frank R.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method for preparing an alumina having controlled pore volume distribution is disclosed. The method requires the presence of 0.1 to 15% by weight of a water soluble aliphatic polycarboxylic acid having from 4 - 22 carbon atoms and of 0.5% to 4.0% of sodium silicate both based on the dry weight of Al2O3, during alumina precipitation. The resultant calcined alumina has a pore volume distribution such that: A. Nitrogen desorption measurements indicate that less than 10% of the total pores as determined by said method fall between 100 - 1200.ANG. in diameter;, B. Nitrogen absorption measurements indicate that between 10 - 50% of the total pore volume as determined fall between 100 - 1200.ANG. …
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Granted January 8, 1980. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended January 8, 1997.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.