| 摘要 |
<p>A composition consisting of carbon powder, water and a dispersing agent. The particle size of the carbon powder is less than 100 mu m, preferably less than 40 mu m. The composition is obtained by preparing a mixture of about 1-20% by weight, preferably about 10% by weight, of carbonaceous powder, water and 0.02-4% by weight of dispersing agent. The dispersing agent is selected preferably from polyelectrolytes, such as alkali metal and ammonium salts of polycarboxylic acids, and polyphosphates. These substances possess the property of charging the powder particles of carbon and the impurity particles in a different degree. This different charging is utilized to separate impurity particles from carbon particles, whereupon the purified composition is suitably dehydrated to attain an increased carbon powder concentration of, for instance, 50-80% by weight.</p> |
