Equilibrium and kinetic data of adsorption and separation for zirconium and hafnium onto MIBK extraction resin

The equilibrium and kinetics of methyl isobutyl ketone(MIBK) extraction resin for adsorption and separation of zirconium and hafnium were studied under the different conditions of acidity,initial total concentrations of zirconium and hafnium and temperature.The equilibrium data of both zirconium and hafnium are found to follow the Freundlich adsorption isotherm,and the Freundlich isotherm constants(KF) are 3.53 and 0.64 mg/g,respectively.The equilibrium data of zirconium also fit the Langmuir adsorption isotherm,and the saturation adsorption capacity(Qmax) and the Langmuir isotherm constant(KL)are 75.93 mg/g and-0.012 7 L/g,respectively.The obtained kinetic data of both zirconium and hafnium are found to fit the HO pseudo-second-order kinetic model,and the rate constants of pseudo-second-order equation(k2) are-0.019 and 0.41 g/(mg·min),respectively.Column tests show that the MIBK extraction resin could be used as efficient adsorbent material for separating hafnium from zirconium.

Progress in Solid-Liquid Extraction Resin for Separation of Rare Earth Elements

The latest development in solid-liquid extraction resin for the separation of REE was reviewed. The chemistry of inorganic supports based on diatomite, silica gel or alumina as well as organic supports based on cellulose, chitosan natural macromolecular support and poly(styrene-divinylbenzene), polyacrylate, aldehyde polymer, polyurethane, polyacrylonitrile synthetic macromolecular supports was covered, low molecular weight extractants such as acidic, organophosphorus, amine, macrocyclic compounds as well as macromolecular extractants were outlined. The different approaches involving ion exchange, ion-pair and chelating separation mechanisms were discussed. Physical adsorption, enclosing and chemical bonding mechanisms about extractants immobilized on solid supports were presented. The relation between resin shape and the property of packed columns was highlighted. Modern synthetic techniques such as molecular assembly, ionic imprinting, chemical modification for the preparation of resins were described. Basic fundamentals, advantages and synthetic methods of novel solid-liquid extraction resins as well as possibilities to improve resins performance were introduced.

ADSORPTION OF GOLD ON TBP EXTRACTING RESIN FROM HCI SOLUTION

Adsorption of gold on TBP extracting resin from HCI solution was researched. All the effects of factors, such as solution acidity, TBP content,tempo)uture, etc. , on adsorption equilibrium were discussed and the equilibrium equation was formulated. The breakthough time of adsorption process withfixed bed uns studied through experiment.

STUDY ON THE ASSAY QUALITY OF FOOD GRADE GPR BY UV—VIS METHOD

In this paper, the kind of remanent small molecules in unsaturated polyester res(?) (UP resin) , the best extractant and the best suitalbe extractive time for measuring the content of these small molecules were studied using ultraviolet- visible spectrophotometry ( UV-VIS method). According to the principle of additivity lightness absorption for mixid solution, the contents of samll molecules in several kinds of cured UP resin were measured. It is pointed out that the UV-VIS method in the assay quality of food grade GRP products is more suitable to China.

Analysis of rare earth elements in high purity europium oxide

Five trace impurities as Ce, Pr, Sm, Gd, and Dy are separated from europium oxide with P507 extraction resin by extraction chromatography. When determined simultaneously by ICP-AES, the impurities show their recovery ratios between 88% and 105%. A lower than 10% relative standard deviation of these elements is obtained when their contents in europium oxide are 5μg/g. The satisfactory results indicate this simple method is sensitive and accurate. It has been employed in the analysis of these five rare earth elements in 99.99% europium oxide.

Separation of strontium from associated elements with selective specific resin and extraction chromatography

In this paper, separation of Sr from associated elements （Na, K, Ca, Mg, and Ba） was carried out using an extraction chromatographic column packed with Sr selective specific resin consisting of an octanol solution of 4,4＇（5＇）-bis（t-butylcyclohexo）-lS-crown-6 sorbed on an inert polymeric support. Using 8.0 mol/L HNO3 as the eluent, Ba and associated elements were eluted immediately from the column, whereas Sr was strongly retained. The adsorbed Sr could then be stripped from the column as the eluent was changed to 0.05 mol/L HNO~. Complete Sr/Ba separation was demonstrated to be feasible in that Ba could be washed from the column leaving pure Sr by adequate rinsing with 8.0 mol/L HN03. Furthermore, matrix effect could be effectively eliminated and the selectivity of the method was improved. The method was applied for the determination of Sr in the high purity barium carbonate （BaCO3） product and seawater. The recoveries of Sr in 2 samples were determined to be 93.2% and 109%, respectively.