Direct precipitation of uranium from loaded organic in a microreactor

A continuous process to obtain ammonium diurate directly from uranium-loaded organic phase in a microbore tube is presented. The proposed process combines two different steps: multistage stripping and precipitation in a microbore tube. The effects of different operating conditions (residence time, O/A ratio, and flow velocity) on percent uranium removal, production rate, and space-time-yield (STY) have been studied. Percent uranium removal as high as 99.5% is attained within a residence time of 3 min for O/A ratio of 4. Corresponding value of STY is 3000 kg/day-m(3) while ensuring a uranium concentration below 50 ppm in lean organic phase. Numerical simulations are carried out to understand the two-phase flow pattern inside the microbore tube. The results of the simulations are used to substantiate and explain the observed experimental trends.