Uranium Recovery Focuses

Uranium is an actinide element and has the highest atomic mass of any naturally occurring element. In its refined state, it is a heavy, silvery-white metal that is malleable, ductile, slightly paramagnetic, and very dense, second only to tungsten. Many of today’s uranium applications are summed up in the unique properties of its core. Uranium-235 is the only natural element available that has fissile isotopes, a feature that makes it widely used in nuclear power plants and nuclear weapons [1]. However, because small amounts of it are found in nature, it needs to be increased under a process called uranium enrichment and its concentration for use in nuclear power plants.

The use of uranium compounds by humans has a long history, so that the use of uranium oxide to create yellow color in ceramic glazes dates back to 79 BC. Yellow glass containing one percent uranium oxide, by R.T. Gunter from the University of Oxford was found in an ancient Roman villa on the promontory of Posilipo in the Gulf of Naples, Italy. From the late Middle Ages, uranium ores were gradually mined from the Hasborg silver mines at Yakhimovo in Bohemia (modern-day Czech Republic) and used for dyeing in glass products. In the early nineteenth century, these were the only known uranium mines in the world. The isotope U-235 is important because under certain conditions it can readily be split, yielding a lot of energy. It is therefore said to be ‘fissile’ and we use the expression ‘nuclear fission’. Meanwhile, like all radioactive isotopes, they decay [2]. U-238 decays very slowly, its half-life being about the same as the age of the Earth (4500 million years). This means that it is barely radioactive, less so than many other isotopes in rocks and sand (Figure 1). Existing and well-known processes in uranium enrichment included electromagnetism, gas diffusion, chemical, photochemical, and centrifuge. Each country has chosen its own method according to its position in terms of technology and related industry and access to the necessary facilities, so economic estimation and comparison of different methods seems a little difficult (Figure 2).

Figure 1: Show number uranium electrons, protons and neutrons.

Figure 2: Chemical identity of uranium metal.

There are different methods of uranium recovery as such as: Uranium recovery from industrial effluent by ion exchange. The recovery of uranium from nuclear industrial effluent has been studied using laboratory column and polymeric ion exchange resin. The industrial ..the recovery of uranium from wet. In 2005, seventeen countries produced concentrated uranium oxides: Canada (29.7% of world production), Australia (22.8%), Kazakhstan (10.5%), Russia (8.0%), Namibia (7.5%), Niger (7.4%), Uzbekistan (5.5%), USA (2.5%), Argentina (2.1%), Ukraine (1.9%) and China (1.7%) Kazakhstan continues to increase its production and has probably become the largest uranium producer in the world in 2009 with a projected production of 12,826 tons compared to Canada with 11,100 tons and Australia with 9430 tons. In the late 1960s, UN geologists also discovered significant reserves of uranium and other rare minerals in Somalia. The finding was the largest of its kind, with industry experts estimating more than 25% of the world’s known uranium reserves at 800,000 tonnes. The main condition for uranium enrichment is that the uranium substance is gaseous and, because the only useful substance that can be gaseous by reaction with uranium is fluorine, so in combination with various uranium isotopes it appears as uranium hexafluoride. Due to the uniqueness of the fluorine isotope, in combination with different isotopes of uranium, it adds the same weight to them and thus can be used in the centrifuge; Therefore, the main reason for using the UF6 compound for the uranium enrichment process is the uniqueness of the fluorine isotope.

In this article, would like to thank Dr. M. Nasiri the esteemed Dean of the semnan university, for his financial and computer assistance.

1. Tom Soellner (2010) Uranium: war, energy, and the rock that shaped the world.
2. Ian Hore Lacy (2016) Uranium for nuclear power: Resources, mining and transformation to fuel. Woodhead Publishing Series in Energy 47(18): 488.