Utilizing combinations of co‐precipitation, solvent extraction and chromatography to design efficient analytical and preparative 

scale separationsDan McAlister and Phil Horwitz

Eichrom Technologies and PG Research Foundation

Separation Toolbox

Precipitation

Solvent Extraction

Chromatography

(Selective) Dissolution

(Co)PrecipitationPreconcentration Matrix Removal Source Preparation

AgCl BaSO4 PbSO4 CaCO3 BaCO3

CeF3 Fe(OH)3 Calcium‐Phosphate MnO2

Hydrous Titanium Oxide Ca‐oxalate   BiPO4

Separation Factors limited by non‐specific binding

S.L. Maxwell, B.K. Culligan, J.B. Hutchison, R.C. Utsey, D.R. McAlister, “Rapid Determination of Po‐210 in Water Samples,” Radioanalytical and Nuclear Chemistry, in press, (2013) DOI: 10.1007/510967‐013‐2644‐2. 

Library.lanl.gov/radiochemistry/elements.html

Complete Recovery of analyte(s)

Compatibility with Matrix

Redissolve?

Compatibility with Separation Methods

Decontamination?

Additional ppt

Solvent Extraction

Chromatography

“Matrix and High Loading Effects on EXC Resins,” D.R. McAlister, E.P. Horwitz, Eichrom Workshop at 58th Annual Radiobioassay and Radiochemical Measurements Conference, Fort Collins, CO, October 29 to November 2, 2012.

Chromatography

Ion ExchangeExtraction 

ChromatographyRelatively Cheap Reagents

Moderate Selectivity

Moderate Capacity

Resins more Expensive

Superior Selectivity

Limited Capacity

Solvent Extraction

Relatively Cheap Reagents

Higher Capacity/Throughput

Stage Efficiency Limited byEntrainment

Third phase, Interfacial CRUD, solvent degradation

Analytical

Sample

Load Solution

counting

TEVA

UTEVA

Load*

Tc, Np

Th,U

Waste

TRU Am, Pu

Sr Sr

35g Th Metal(2.3 x 1.0 x 1.3 cm)

Dissolve Th8M HNO3 + 0.01M HFComplex

Residual F-

with Boric acid

Raffinate from SX Process 3M HNO3

Th, Pa, U

Y, Sc, Ln(Z>Pm), Po

Ra, Ac, Ln, Y, Sc, Po

To Recycle Ra, Sr

Ac

La-Pm

Ac, La-Pm

Ac‐225 Production

Rare Earths?

Eu

Tb

Production

Production

http://geology.com/articles/rare-earth-elements/

Metal $/kg UsesLa 15 Batteries (10 kg La in a Prius)Ce 15 Catalytic Converter, PolishingPr 105 Alloys, Arc Lights, Welding GlassesNd 98 Magnets, LasersSm 40 MagnetsEu 4000 Phosphor (TV, CFLS)Gd 210 Phosphor, Neutron CaptureTb 2100 Phosphor, AlloysDy 1100 Lasers, LightingHo 1000 Lasers, MagnetsEr 275 Lasers, Glass ColorantTm 4600-13000 Lasers, Portable XRay SourcesYb 1000 Atomic Clocks, Stress GaugesLu 10000 Few (Catalyst)Y 68 Phosphors, Synthetic Garnets

Sc 15000 Alloys, Lamps, Dental LasersAu 45000

DOE Critical Materials for Clean Energy

US DOE Critical Materials Strategy, December 2011.

C&E News, May 30, 2011    Volume 89, Number 22  p. 9  DOI:10.1021/CEN060211130455

Bastnäsite(Ce, La)CO3F

(Y, Ce)CO3F

Monozitemonazite‐Ce (Ce, La, Pr, Nd, Th, Y)PO4       monazite‐Nd (Nd, La, Ce, Pr)PO4monazite‐La (La, Ce, Nd, Pr)PO4 monazite‐Sm (Sm, Gd, Ce, Th)PO4

Ce(IV)

Eu(II)

Yb(II)

Sm(II)

56 58 60 62 64 66 68 70 7210-3

10-2

10-1

100

101

102

103

104

105

106

107

108

LN LN2 LN3

Pm

LuYb

Tm

ErHo

DyTb

GdEu

Sm

NdPrCe

k'

Rel

ativ

e to

La

on L

N2

= 1

Z

La

PO

OH

O

O

PO

OH

O

PO

OH

NR

R OO O

N RR

56 58 60 62 64 66 68 70 7210-1

100

101

102

103

104

105

Ac

Ac

Pm

Pm

Lu

Lu

Yb

YbTm

TmEr

ErHo

Ho

Dy

Dy

Tb

Tb

Gd

GdY

YEu

Eu

Sm

Sm

Nd

Nd

Pr

PrCe

Ce

La

0.05 M HNO3

0.50 M HNO3

TODGA

k'

Z

La

precipitates

Solvent Extraction

0 5 10 15 20 25 30 3510-4

10-3

10-2

10-1

100

101

102

103

Bed Volume = 19.4 mLBed Height = 20.4 cmColumn Diameter = 1.1 cmFlow Rate = 5.0 mL/min = 5.3 mL/cm2/min = 3.9 min/Bed Volume = 2.225-53 m

Lu(III), 0.5 mg

Yb(III), 5 mg

Eluant1.5 M HNO3

Load0.10 M HNO3

ppm

/mL

Bed Volumes

Lu/Yb Separation on LN2 Resin, 50oC, 5 mg Yb

0 5 10 15 20 25 30 3510-4

10-3

10-2

10-1

100

101

102

103

Bed Volume = 19.0 mLBed Height = 20.0 cmColumn Diameter = 1.1 cmFlow Rate = 5.0 mL/min = 5.3 mL/cm2/min = 3.8 min/Bed Volume = 3.425-53 m

Lu(III), 0.5 mg

Yb(III), 25 mg

Eluant1.5 M HNO3

Load0.10 M HNO3

ppm

/mL

Bed Volumes

Lu/Yb Separation on LN2 Resin, 50oC, 25 mg Yb

Displacement Chromatography

Application of EXC to Large Scale Separations

High cost of resins High Value Products

Limitation Consequence(s)

Resin Stability

Analytical Applications

Application of EXC to Large Scale Separations

Low Capacity High Value Products

Limitation Consequence(s)

Scavenge trace elementsfrom large stream

Add value to existingstream

Enable better analyticalresults

Cerium Removal (analysis)

10-3 10-2 10-110-1

100

101

102

103

104

k' Ce-139 on UTEVA-3 vs NaBrO3

0.75MY/Yb(NO3)3

Adjusted towith HNO3

k'-C

e

[NaBrO3], M

100-150 m, 21(1)oC, 1h

1.0M HNO3

1.5 M HNO3

2.0 M HNO3

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0100

101

102

103

104

105

Dw Fe-55 from YCl3/Rare Earth Feed

1x8

WBEC

Dw

-Fe

[HCl], M

TEVA

HCl concentration achievedby adding 12M HCl to YCl3Rare Earth feed solution

2h, 21(1)oC, 30-60 mesh

Iron Removal (analysis)

Iron Removal (analysis)

10-1 100 10110-1

100

101

102

103

104

105

Dw Ni, Ca, Mg,Na, K, Al <1

Co

Cu

Bi

In

GaFe(III)

Pb

Zn

Dw on TEVA from HCl

Dw

[HCl], M

2h, 21(1)oC, 30-60 mesh

Cd

Heavy Lanthanide Separations (analysis)

1E-3 0.01 0.11

10

100

1000

NdPr

Ce

Y-90 as Heavy Ln analog

k'-Y

[HCl], M

k' Y-90 on LN2 from 1M LnCl3 vs HCl50-100 m, 21(1)oC, 2h

1.0 M LnCl3

La

Sc Separations (analysis)

10-1 100 10110-1

100

101

102

103

104

105

Sc Yb Y Eu La

k'

[HCl], M

UTEVA-3

10-1 100 10110-1

100

101

102

103

104

105

k'

[HNO3], M

UTEVA-3