二氧化碳常温浸提法回收铬渣中铬的研究

Study on the recovery of Cr(Ⅵ) from chrome residue by extracting with carbon dioxide at normal temperature

根据铬渣的元素和物相组成以及铬(Ⅵ)在各物相中的分布和溶解性质,提出用二氧化碳浸提法回收铬渣中铬(Ⅵ)。在实验室对采用二氧化碳浸提铬渣回收铬(Ⅵ)进行了研究,结果表明:常温常压下,浸提3 h,可从铬渣中回收65.03%的铬(Ⅵ),浸提液返回生产过程水浸熟料工序中作浸洗液用,不但能提高铬资源利用率,还可大幅度减少污染源量,并为下一步铬渣解毒处理和综合利用创造有利条件。

According to the elemental composition, phase composition, the distribution and solubility of Cr（ Ⅵ ） in chrome residue, a novel extracting process for recovery of Cr（Ⅵ） from chrome residue with carbon dioxide at normal temperature was given and investigated in the experiment. The results showed that the recovery rate of Cr（ Ⅵ） in chrome residue was above 65.03% when the extracting process was carried out in 3.0 h at normal temperature and pressure. Then,Cr （ Ⅵ） - containing leaching solution would be used as the extraction solvent in leaching calcines procedure of chromic salts production. Not only was it favorable to raising the utilization rate of chromic resources ,but decreasing substantially chrome residue pollution. And also it could create favorable condition for the detoxification and comprehensive utilization of chrome residue in future.