China Nonferrous Metallurgy

Taking the northern by-product scandium sandstone uranium ore as the research object, this study addresses the problem of low uranium leaching rates caused by pore blockage in high-acid leaching systems. An innovative method is proposed using the organic chelating agent nitrilotriacetic acid (NTA) under low acid concentration to enhance the co-leaching of uranium and scandium, aiming to improve the co-leaching of uranium and scandium. Research on the NTA-enhanced co-leaching of uranium and scandium was conducted using northern by-product scandium sandstone uranium ore as the subject. The effects of single factors on leaching were examined, including sulfuric acid concentration, nitrilotriacetic acid concentration, fluorinated surfactant concentration, and leaching time. Based on this, a four-factor two-level orthogonal design experiment was carried out. Through linear regression analysis and standardized effect Pareto chart analysis, the factors significantly affecting the uranium and scandium leaching were identified, and a linear regression equation model correlating leaching with each factor was constructed. The results indicate that, taking P<0. 000 1 as the criterion, sulfuric acid concentration has a significantly greater effect on uranium leaching than leaching time and NTA concentration; the important factors affecting scandium leaching are sulfuric acid concentration and leaching time. Based on the identified significant factors (P<0. 000 1) and significant quadratic factors (0. 01