E ects of Reagent Concentration and Particle Size on Di usion Rate of Mixed Ores with Rare Elements
نویسنده
چکیده
The leaching reaction kinetics of weathered crust elution-deposited rare earth with mixed ammonium salts was studied. The in uence of concentration of reagents and particle size of ore on leaching rate was investigated. The results showed that the di usion process and leaching rate could be improved by increasing reagents concentration and decreasing leaching owing rate and particle size. The leaching process could be explained with the shrinking core model, which could be controlled by the di usion rate of reacting reagents in porous solid layer. The leaching rate obeyed the equation as 1− 2/3η − (1− η) = 7.126× 10−4C0.3038R0.1942t.
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