Patent · US Expired

High capacity coconut shell char for carbon molecular sieves

US5164355A · kind A · utility

20Cited by
8References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 23, 1991
Grant dateNov 17, 1992
Priority date
Expiry dateJan 23, 2011

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC01B32/306
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

A coconut shell char having a high oxygen volumetric capacity is provided by crushing and sizing coconut shells to form granules which are then heated in flowing inert gas at a temperature ramp rate of about 2.degree. to 12.degree. C. per minute to a peak temperature of 775.degree. to 900.degree. C. which is then held so that the total heating time is up to 8 hours and thereafter the granular char is cooled in an inert gas atmosphere. The granular char thus produced is oxygen selective in air separation without further modification to narrow the openings of its micropores and has an oxygen volumetric capacity in excess of 8.0 cc/cc. Further modification of this char is provided by contacting it with an oxidizing atmosphere of carbon dioxide or a mixture of inert gas and carbon dioxide, H.sub.2 O or O.sub.2 at temperatures ranging from 650.degree. to 900.degree. C. until the gasified char has been altered so that its volumetric oxygen capacity is greater than 9.0 cc/cc. The coconut shell char can be further modified directly as prepared or following a gasification procedure by treatment with volatile carbon-containing organic compound which is pyrolyzed to form carbon which reduces …

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