| 摘要 |
<p>Method for de-inking printed waste paper comprises first soaking it with surfactants and opt. with alkali, then treating with terpene hydrocarbons or alcohols, aliphatic or aromatic hydrocarbons and alcohols or their mixt., with addition of carriers or collectors contg. Ca soaps. The resulting suspension is then classified conventionally. The new feature is that carriers with a large surface area are used and these have applied to their surface a soap which is subsequently converted to a Ca soap. Esp. the surface is first treated with oleic acid then this is saponified with an alkali. The carrier is pref. mechanical wood pulp, sawdust, porous plastics and bark waste. Since only the surface acts as collector lower amts. of chemicals are required c.f. use of Ca soap particles plus pineol. The particles of flaculate formed are larger and more easily sepd.; generally the carrier particles float to the surface.</p> |
