Patent · US Expired

Modified carbon molecular sieves for gas separation

US5098880A · kind A · utility

24Cited by
4References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 30, 1990
Grant dateMar 24, 1992
Priority date
Expiry dateAug 30, 2010

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC01B2210/0082
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

A process is provided for making a modified carbon molecular sieve which is suitable for separating gases having different adsorption rates on the sieve. The process involves modifying a starting sieve support having a majority of micropores with an effective pore size of about 4.5 to 8 angstroms, with a two-step process in which the sieve is contacted with two different volatile carbon-containing organic compounds, preferably hydrocarbons, which have different molecular dimensions. The compound used in the first step is larger than that in the second step, so that the pore openings of the micropores of the support are narrowed successively in two distinct steps without filling the micropores themselves. The invention also discloses an improved carbon molecular sieve and the separation of gases, such as oxygen from nitrogen, by the use of this improved adsorbent.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.