| 摘要 |
PURPOSE:To obtain pitch which is useful for use in the production of carbon materials, which produces carbonized materials in high yields and has a high softening point, by a method wherein a nitrating agent is mixed with tar and the mixt, is heated to form pitch. CONSTITUTION:A tar such as coal tar or ethylene-pyrolysis tar is mixed with a nitrating agent such as nitric acid or acetyl nitrate in an amount of 3-20% the nitrating agent. The mixt. is heated at a temp. of 150-400 deg.C to form pitch. The softening point of the produced pitch can be properly determined by adjusting a mixing ratio of the nitrating agent to the tar. When the mixing ratio of the nitrating agent to the tar is not more than 3%, th pitch having a softening agent of not more than 100 deg.C is produced. When the amount of the nitrating agent is not less than 20%, the pitch having a softening point of not less than 200 deg.C is produced. But, at the same time quinoline-insoluble matter is formed. Hence, the use of the nitrating agent in an amount of not less than 20% is not preferred. |
