| 摘要 |
<p>PURPOSE:To make it possible to separate zinc of a high purity from zinc dross by adding a specified weight percent of zinc chloride powder to half-melted zinc dross. CONSTITUTION:When more than 0.2% of zinc chloride powder is added to zinc dross heated to a half-melted condition, zinc contained in the dross is separated and zinc of 99.7% pure and containing little iron and aluminum is obtained. When the zinc chloride is added to a half-melted zinc dross, it becomes a gas due to its high vapor pressure, and becomes poisonous because a part of gas is disintegrated into chlorine gas. Therefore, it is necessary to make a closed type treatment furnace and gases produced during the course of treatment have to be sucked and removed. Since zinc chloride has a hygroscopic property and handling of it is not so easy, less than 80wt% of sodium chloride is added to zinc chloride to improve its property and to decrease vapor pressure at the treating temperature.</p> |
