Comparison of hollow fiber membrane and solvent extraction techniques for extraction of cerium and preparation of ceria by stripping precipitation (original) (raw)

BACKGROUND The extraction of cerium by hollow fiber supported liquid membrane using tri-octyl methyl ammonium chloride (TOMAC) as mobile carrier was studied and the result was compared with solvent extraction data. The effect of different parameters such as pH, flow rates, extractant, metal ion and strip solution concentration on cerium extraction was investigated. RESULTS These parameters were optimized for maximum cerium flux and were found to be: pH 1.0, 0.1 M TOMAC, 290 mL/min feed solution flow rate, 150 mL/min strip solution flow rate and 0.9 M H 2 SO 4 as strip solution. The parameters were also optimized for solvent extraction study. The number of stages and A:O ratio for extraction and stripping were determined from McCabe-Thiele diagrams. The extracted species was determined to be 3 4 2 3 3) () (SO Ce NCH R. The selective separation of cerium in presence of various other metal ions such as iron, copper, zinc, cobalt, nickel and manganese using HFSLM was carried out and the separation factor values were found to be in the order of α Ce/Fe < α Ce/Cu < α Ce/Mn < α Ce/Zn < α Ce/Co < α Ce/Ni. Finally high pure (99.99%) CeO 2 was prepared by stripping precipitation with oxalic acid and thermal decomposition at 900 o C for 1h. This article has been accepted for publication and undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process, which may lead to differences between this version and the Version of Record. Please cite this article as