氨—碳铵法浸出含锌烟灰

研究氨—碳铵体系中pH、总氨浓度、液固比(L/S)、反应温度、反应时间等因素对三种含锌烟灰中锌和主要杂质元素浸出行为的影响。结果表明,较佳的工艺条件是:浸出剂总氨浓度9mol/L、pH=10.00、L/S=5、反应温度50℃、反应时间60min。此时锌浸出率大于80%。

Dissolving behavior of ammonium paratungstate in(NH_4)_2CO_3-NH_3?H_2O-H_2O system

The effects of temperature, ammonia concentration and ammonium carbonate concentration on the dissolving behavior of ammonium paratungstate were studied in（NH4）2CO3-NH3？H2O-H2O system. The results show that rising temperature, prolonging duration, increasing ammonia concentration and decreasing ammonium carbonate concentration favor dissolving of ammonium paratungstate at temperature below 90 ℃, while the WO3 concentration decreases after a certain time at temperature above 100 ℃. Furthermore, the undissolved tungsten exists in the form of either APT·4 H2O below 90 ℃ or pyrochlore-type tungsten trioxide above 100℃. In dissolving process, the ammonium paratungstate dissolves into paratungstate ions followed by partially converting to tungstate ion, resulting in the coexistence of the both ions. This study may provide a new idea to exploit a novel technique for manufacturing ammonium paratungstate and pyrochlore-type tungsten trioxide.

从黄铜熔炼渣中回收铜,锌

试验了碳铵—氨体系浸取黄铜熔炼渣的工艺条件。含Cu6.76%、Zn31.27%的黄铜熔炼渣经稀碱洗涤后,在2mol/1碳铵—2mol/1氨水体系中,液固比为5:1,50℃浸取1h,铜、锌的浸出率均达85%以上。在浸出液中加适量碱后,使铜、锌初步分离。在灼烧Cu(OH)_2工艺所得后形成的CuO中,含Zn5—7%。

磷酸锌防锈颜料低成本工艺的探索

采用氨 -碳铵溶液净化低度氧化锌生产磷酸锌的新工艺 ,克服了直接法固 -液反应的弊病 ,较明显地降低了原料成本。