Leaching Uranium Ore Using Auxiliary Materials:Hydrosiloxane Surfactants

As the nuclear becoming the most widely used energy source in military and power generation of China,exploring uranium which as a key element for nuclear has a great significance for providing an adequate nuclear resource.However,lots of Chemical hazards were created by dangerous chemicals which has a complicated structure and indecomposable coat were dispersed in soil and plant in uranium exploration and uranium smelt,the uranium waste and radioactive waste will flow in underground water and heap up in surface,which endanger life and health of surrounding residents and the environment is radiated.So,it has great significance for reducing environmental hazards,ensure that resident safety,be efficient and energy-saving by uranium exploration.The results show the range of micelle concentration which from 0.5mg/L to 2 mg/L in surface tension test by adding different concentration surfactants in leaching liquor and the surface tension of lixivium which without surfactants reached 74.440 mN/m.With the H–380 and H–350added in the leaching solution,the surface tension decreased by 52.9%and56.3%,reaching to 35.040 and 32.536 mN/m at 10mg/L,respectively at25℃.The results of agitation leaching experiments show the leaching rate of uranium increased by 10%and 19%,reaching to 83%and 93%by adding 1mg/L H-380 and H-350,respectively and the micelle concentration is 1 mg/L was confirmed.Meanwhile,besides above part,the best technological parameters were selected as flowed:contact time is4h,the molar ratio of Na₂CO₃:NaHCO₃ was 1:1,solid liquid ratio is 1:6and the agitation speed was 400 rpm.The shrinking core model was chosen for explaining the agitation leaching course and the kinetics of leaching shows the leaching of uranium in raw ore is mainly controlled by mix kinetic,thereinto,the boundary diffusion is the primary mode of diffusion.However,with the surfactants added in leaching solution,the uranium reaction rate is accelerated obviously and diffusion control play a major role in the leaching process of uranium.This can be explained by that the surfactant could reduce the thickness of boundary film,enhancing the efficiency of the contact in solid-liquid phase,change the kinetic mechanism by produce coupling between the diffusion and chemical reaction,increase and accelerate uranium extraction in leaching process.This study providing scientific technological parameter for uranium extraction and solved the low leaching rate in hydrometallurgy in China.