Enlargement of the micropores of a caking bituminous coal by controlled oxidation

✍ Scribed by Salvador Leon; Myrna Klotzkin; Gary Gard; Paul H. Emmett

• Publisher: Elsevier Science
• Year: 1981
• Tongue: English
• Weight: 512 KB
• Volume: 60
• Category: Article
• ISSN: 0016-2361
• DOI: 10.1016/0016-2361(81)90217-9

✦ Synopsis

In a study of the enlargement of pores of coals it has been found that treatment of a bituminous coal (PSOC No. 371, from the Pennsylvania State University Coal Section) with a 5:95 O,:N, stream 4 h at 400°C increases the surface area as measured by nitrogen adsorption at 77K by a factor of at least 50 to a value 52 rn* 9-l. The increase in pore size was accompanied by a 9.7% weight loss. Simultaneously, the area as measured by carbon dioxide at 195K increased from 61 to 136 m2 g -' and that measured by carbon dioxide at room temperature increased from 125 to 237 m2 g -'. Attempts to enlarge the pores by oxidation with hydrogen peroxide or ozone were unsuccessful. A Pittsburgh coal subject to a small percentage of oxygen in nitrogen or steam at 300 to 400°C showed a surface area as measured by nitrogen adsorption of less than 1 m* g -' both before and after such pretreatment. This same coal with a 5:95 02:N2 stream for 4 h at 450°C showed a surface area of 110 m2 g-' measured by nitrogen adsorption at 77K.