Iranian Journal of Chemical Engineering (IJChE)

Abstract In this work, recovery of uranium from industrial waste was investigated experimentally using solvent extraction technique. Di 2-ethyl hexyl phosphoric acid (D2EHPA), tri-n-octyl phosphine oxide (TOPO) and their synergetic mixture was used as extractant in the experiments. Nitric acid solution was selected the best medium for extraction of uranium from the industrial waste. The extraction process has been investigated as a function of extractant concentration, diluents type, nitride acid pH, contact time, initial uranium concentration and temperature. The experiments were performed in batch mode. Kerosene was selected as the best diluent for the extractants. In the experiments it was found that, high temperature is beneficial for TOPO or D2EHPA extraction but low temperature is profitable for their synergistic effect. The results indicate that the extraction rate for uranium was controlled by diffusion. The best stripping agent for TOPO 0.05M or D2EHPA 0.15M and their mixture were Na2CO 3 2M, by 96.2%, 54.3% and 57% uranium recovery respectively. McCabe curve showed that single theoretical stage is sufficient for uranium extraction more than 95 percent.

Abstract Filter cakes obtained in the conventional acid leaching of zinc concentrate are considered a major secondary source for zinc. Solvent extraction may be utilized for the selective separation of zinc from other elements in hydrometallurgical processing of such resources. In the present work, extraction of zinc from the solution obtained from sulfuric acid leaching of cold purification filter cake of Angouran concentrate were performed by using D2EHPA as the extractant. The effects of extractant concentration diluted in Kerosene, solution pH and phase ratio (O:A) were investigated and their optimized values were obtained to be 40 vol.%, 2.5-3 and 4:1, respectively. Under these conditions, 98.8% of Zn could be extracted.