| 摘要 |
<p>PURPOSE:To recover liquid-metal gallium in high purity, by adding and mixing a binder into a gallium-bearing material containing the fine grains of gallium compounds, by heating and burning the resulting mixture, and by applying vacuum thermal decomposition to the above. CONSTITUTION:A gallium-bearing material containing the fine grains of gallium compounds hitherto treated as waste, such as dross, is used as a raw material. An inorganic and/or organic binder is added and mixed into the above-mentioned raw material to be treated. At this time, alumina hydrosol, clay minerals, etc., are used as the inorganic binder and, as the organic binder, PVA, polyethylene glycol, etc., are used, and it is preferable the additive quantity to at least about 0.001pts.wt. per pts.wt. of the above-mentioned fine grains. The above mixture is preferably dried previously and is compacted, if necessary, into a sheet-like state, etc., and is then subjected to heating and burning at about 300-1,000 deg.C as pretreatment. The resulting burnt material in which the fine grains of gallium compound are bound together and made difficult to scatter is subjected to vacuum thermal decomposition at about 10<-5>-100mm at about 1,000-1,300 deg.C. The resulting liquid-metal gallium is recovered by separating the decomposition residue by filtration.</p> |
