铬渣中铬的氧化法浸出工艺条件的研究

Study on leaching process of chromium from chromium residue by oxidation method

采用碱性条件下氧化处理铬渣的方法研究了氧化剂种类及各工艺条件对铬渣中铬浸出量的影响。结果表明,NaOH加入量为0.12 g,氧化剂NaClO3的加入量达0.2 g或Na2C2O6加入量为0.2 g时,在80℃水浴条件下反应120 min后,Cr(Ⅵ)与总铬的浸出量最高。延长反应时间和提高水热反应温度,有利于提高铬渣中铬的浸出量,但温度过高会导致铬渣中Cr(Ⅵ)及总铬的浸出量下降。

The inffluence of the type of oxidants and technical conditions on the amount of chromium leaching from chromium residue was studied by oxidation method under alkaline condition. The optimal operation parameters are shown as follows ：0. 12 g of sodium hydroxide ,0.2 g of NaC103 or NaC103 as the oxidant,80℃ of water bath temperature and 120 minutes of reation time. The highest amount of Cr（ Ⅵ ） and total chromium leaching from the chromium residue can be obtained. The long reaction time and high hydrothermal temperature are beneficial to the leaching of Cr（ Ⅵ ） and total chromium from the chromium residue. However, too high temperature results in the decrease of the amount of lixiviation Cr（ Ⅵ ） and total chromium.