Methods of treating coal to remove sulfur and ash
US4328002A · kind A · utility
Inventor
Key dates
| Filing date | Jun 15, 1981 |
| Grant date | May 4, 1982 |
| Priority date | — |
| Expiry date | Jun 15, 2001 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC10L9/02
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
Methods of treating coal to remove sulfur and ash are provided which involve the steps of preconditioning coal particles in the presence of an aqueous solution of an oxidizing agent, washing said pretreated coal with water, contacting said coal with an aqueous solution of an oxidizing agent until an exothermic reaction between the coal and oxidizing agent peaks and the pH drops to the range of 2 to 3, removing the coal from the oxidizing agent, contacting the coal with a passivating agent until the temperature of the coal drops and the pH rises into the range 3 to 5, neutralizing the coal up to a pH of about 9, washing said coal with water and drying said coal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.