163. Effect of heat-treatment on compacted natural graphite

• Publisher: Elsevier Science
• Year: 1965
• Tongue: English
• Weight: 108 KB
• Volume: 3
• Category: Article
• ISSN: 0008-6223
• DOI: 10.1016/0008-6223(65)90229-0

✦ Synopsis

petroleum cokes, particularly with regard to ash content and electrical resistivity. However, these results suggested that anthracite would (technically) become an acceptable filler for carbon electrodes, in the aluminium industry, if its ash content were reduced to a level comparable with petroleum coke. To reduce the ash content, anthracite has been heated in one atm of chlorine at 2000°C. In 20 tin, the ash content of 100x150 mesh sample was reduced from 5.3% to 0.28%, with amounts of the individual elements reduced sufficiently so that specifications set for aluminium electrodes are met. Carbon bodies were now prepared from the 100x150 mesh demineralized anthracite and from 100x150 mesh petroleum coke, calcined at ca. 1400°C. Pitch level and molding pressures were adjusted so that the final baked bodies would have very similar bulk densities. Properties measured on the bodies were electrical resistivity, compressive strength, and reactivity to carbon dioxide. Additional results are discussed for bodies made from anthracite, calcined at ca. 14OO"C, and then heat treated between 1750 and 2250°C in a chlorine atmosphere.