Pressure gradient passivation of carbonaceous material normally susceptible to spontaneous combustion
US6146432A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 15, 1999 |
| Grant date | Nov 14, 2000 |
| Priority date | — |
| Expiry date | Jul 15, 2019 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC10L5/00
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
This invention is a process for the passivation or deactivation with resp to oxygen of a carbonaceous material by the exposure of the carbonaceous material to an oxygenated gas in which the oxygenated gas pressure is increased from a first pressure to a second pressure and then the pressure is changed to a third pressure. Preferably a cyclic process which comprises exposing the carbonaceous material to the gas at low pressure and increasing the pressure to a second higher pressure and then returning the pressure to a lower pressure is used. The cycle is repeated at least twice wherein the higher pressure may be increased after a selected number of cycles.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.