Method for efficiently removing and recovering uranium in water by utilizing titanium-based titanium dioxide nanotube array electrode

Abstract

The invention discloses a method for efficiently removing and recovering uranium in water by utilizing a titanium-based titanium dioxide nanotube array electrode. The method adopts an anatase phase titanium dioxide nanotube array electrode and a stable good-conductivity material as a cathode and an anode respectively to construct an electrochemical reduction system, hexavalent uranium in a solution is subjected to electrochemical reduction to form tetravalent uranium by utilizing a stronger coordination effect of anatase phase titanium dioxide and uranyl ions in the absence of external additives, and the tetravalent uranium adheres to the electrode surfaces; and after electrochemical reduction enrichment is completed, a tetravalent uranium-rich anatase phase titanium dioxide nanotube arrayelectrode is taken out from the solution, so that high-efficiency reduction removal of the uranium in the wastewater, the groundwater and / or the seawater can be realized. The method provided by the invention has a wide application range, and can realize high-efficiency removal and recover of the uranium for the wastewater, the groundwater and the seawater containing a high concentration of dissolved oxygen, a high concentration of a carbonate and a low concentration of the uranium.

Description

technical field [0001] The invention belongs to the field of waste water treatment and precious metal resource recovery, and relates to a method for efficiently removing and recovering uranium in water by using a titanium-based titanium dioxide nanotube array electrode. Background technique [0002] Uranium is a core element in the development and utilization of nuclear energy, and it is toxic and radioactive as a heavy metal. In recent years, more and more countries such as China, the United States, and Canada have reported that the uranium content in surface or groundwater exceeds the drinking water standard (30 μg / L) set by the World Health Organization, which has caused huge damage to the ecological environment and human life. harm. At the same time, the demand for uranium is also increasing worldwide. For example, China is building 30 nuclear power plants with a total power generation capacity of 29,240 megawatts. The huge demand for uranium will become a limiting fact...

AI Technical Summary

Problems solved by technology

Although the electrochemical removal of uranium has the above advantages, it still faces the following problems: 1. The electrochemical method using the traditional electrode relies on the self-catalysis process on the electrode surface, that is, when the uranium reduction product on the electrode surface accumulates in a sufficient amount, the reaction can be completed. Efficient, when the concentration of uranium in the solution is low, a sufficient amount of tetravalent uranium coating cannot be formed, resulting in the inability of the reaction, which leads to the unsatisfactory effect of this method on the removal of uranium in water environments with low uranium concentration

2. Carbonate, as a common inorganic ion in nature, can form a very stable complex with uranyl ions, uranyl carbonate. When carbonate exists in water, hexavalent uranium and carbonate form a stable complex. The reduction and removal reaction requires a large overpotential, which greatly reduces the reaction efficiency

3. Quavalent uranium, the reduction product of hexavalent uranium, is easily oxidized by oxygen. When dissolved oxygen exists in water, there will be a very violent oxygen reduction side reaction in the reduction process of uranium, which seriously reduces the reduction and removal efficiency of uranium.