Uranium Extraction from Solid Waste as Nitrate Complex with D2EHPA, TOPO and their Synergistic Mixture

Ghaemi, A.; Rahmati, A.

Uranium Extraction from Solid Waste as Nitrate Complex with D2EHPA, TOPO and their Synergistic Mixture

Document Type : Full article

Authors

A. Ghaemi ¹

A. Rahmati ²

¹ School of Chemical Engineering, Iran University of Science and Technology, Tehran, Iran

² Nuclear Fuel Cycle Research School, Nuclear Science and Technology Research Institute, Amirabad, Tehran, Iran

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.

Keywords

Uranium Recovery

Solvent Extraction

TOPO

D2EHPA

Synergistic