methodology and application of automation in radiochemical ..."extraction chromatographic...

Methodology and Application of Automation in Radiochemical Separations

and AnalysisJay W. Grate and Matthew J. O’Hara

Pacific Northwest National Laboratory

NKS Workshop on Radioanalytical Chemistry

Roskilde, Denmark, September, 2013

United States Department of Energy (DOE) Multi-program National Laboratories

Lawrence Livermore

Pacific Northwest

IdahoLawrence Berkeley

Argonne

Sandia

Los AlamosOak Ridge

Brookhaven

Office of ScienceNational Nuclear Security AdministrationOffice of Nuclear Energy, Science & Technology

Hanford Nuclear Site in Washington StateNuclear waste storage tanksContaminated earth and groundwaterNuclear waste processing facilities

Under constructionColumbia River

Radiochemical analysis is critical in several activities

CharacterizationMonitoringRemediationProcessing waste into stable waste formsLong term stewardshipNuclear archeology

Hanford Nuclear Site Facilities

PUREX PlantExtract Pu from irradiated U

N-reactor next to Columbia River

Nuclear Waste Storage Tanks

Hanford Waste Treatment Plantplannedunder construction

Drilling and seismic testing prior to construction

June 2011 aerial view

http://www.hanfordvitplant.com/gallery_view.php?id=134

Pretreatmentfacility

AnalyticalLab

HLW

LAW

Radionuclides of Interest

Fission ProductsSr-90Tc-99

Transuranic ElementsPuAmNp

Half lives, activity, mobility in the environment, biological activity…

Sr-90Tc-99 Cs-137

Sample to Analysis in Radiochemistry

Dissolution

Extraction Chromatography

Precipitation

Anion Exchange

Single Bead Methods

Mass spectrometry

SEPARATION(S)Resolve interferences

Radiometric

Matrix Adjustment

Speciation Control

SAMPLE PREPARATION

DETECTION

Other elemental methods

Separations

Mass spectrometry

SEPARATION(S)Resolve interferences

Radiometric

SAMPLE PREPARATION

DETECTION

, , spectral

Isobaric, molecular ion, spectroscopic

Fluid handling methodology

Separation chemistry

Step Analyte retention

Load sample

Strong

Wash Strong

Elute Weak or unretained

…

Contrast with high resolution chromatography separations based on migration time

Extraction Chromatography

Anion Exchange

Separations

Mass spectrometry

SEPARATION(S)Resolve interferences

Radiometric

SAMPLE PREPARATION

DETECTION

, , spectral

Isobaric, molecular ion, spectroscopic

Fluid handling methodologyFlow Injection (FI)Sequential Injection (SI)Separation-optimized SIWhatever works for the application

Laboratory automationAnalyzers for process analysis at-siteRadiochemical sensors for environmental monitoring

Fluidic system may link:Directly to detectorFraction collector

Flow Injection and Sequential Injection Analysis (FIA and SIA)

Sequential InjectionReversible fluid drive

Digital syringe pump

Holding coil to stack zones of reagentsVariable sample size controlled by software rather than fixed sampling coilScaleable fluidics architecture suitable for many applications

Sequential Injection Separation

Pump

Reagent,8M HNO3

Waste

Sample

Holding  CoilMultiposition Valve

SorbentColumn

Flow‐Through

ScintillationDetector

WasteCarrier, H2O

Sequential Injection Separation of Sr-90

Sr-ResinExtraction chromatographic resin (crown ether)

Standard

Pre-processedNuclear Waste

Flow through liquid scintillation detection and quantification

Sequential Injection Separation

Sequential Injection Separation

Separation-optimized Sequential Injection

Enables rapid change from one solution composition to

another, even with large-bore holding coils

Separation-optimized Sequential Injection

Enables rapid change from one solution composition to

another, even with large-bore holding coils

Gross Actinides Separation on TRU-Resin

Load, wash, & elute

Multistep Separations of Actinides

TRU-resinCMPO in TBP

A number of actinide separations can be implementedCompatible with ICP-MS detection

Actinide Analysis by Sequential Injection Separation with ICP-MS Detection

place analyte in consistent matrixaddress interferences:

isobaric , molecular ion, and spectral interferences

Actinide separation shown addresses 241Pu/241Am, 239Pu/238UH

237Np/238U

Automated Separation with On-line Detection

Dissolution

Extraction Chromatography

Precipitation

Anion Exchange

Single Bead Methods

Mass spectrometry

SEPARATION(S)Resolve interferences

Radiometric

Matrix Adjustment

Speciation Control

SAMPLE PREPARATION

DETECTION

Separation Issues Analytical Issues

Solution and reagent conditions to obtain consistent reproducible behavior time-after-time

Nearly always find something that needs to be addressed in automated format with on-line detection

Separation recovery

Column crossover

On-column reaction chemistry

Carryover

Column reusability

Detection limit

Sample throughput

Separation efficiency

Detection efficiency

Carryover

Application specific criteria

Applications Automated Radiochemistry

Analyses enabled by automation

Process monitoring “at-site”

Radionuclide sensors for ground water “at-site” or “in situ”

Analyses made more efficent* by automation

Laboratory automationfasterreduced labor/costreduced worker exposure to radiationmore consistent procedures with less training

Automated Monitoring: At-site Process Analysis

Dissolution

Extraction Chromatography

Precipitation

Anion Exchange

Single Bead Methods

Mass spectrometry

SEPARATION(S)Resolve interferences

Radiometric

Matrix Adjustment

Speciation Control

SAMPLE PREPARATION

DETECTION

Automated Monitoring: Total Tc-99

Anion Exchange

SEPARATION(S)

Radiometric

Matrix Adjustment

Speciation Control

SAMPLE PREPARATION

DETECTION

Alkaline high salt matrixacidificationoxidation of all Tc to TcO4

-

(pertechnetate anion)

retain TcO4- in weak acid

multi-eluent wash elute TcO4

- in strong acid

flow through solid scintillator detector

beta emitter

Monitor Fluidic System

Monitor Fluidic System

Microwave-assisted Sample Preparation

Digestion cell

Reagent line Vent line

Cell cap

A

B C

D

E

Automated Tc Monitor

Monitor Fluidic System

Rapid Column Separation of TcO4-

Flow reversalHigh flow rates

Species captured on the “top”of the column are then rapidly released in reverse flowFlow rates up to 8 mL/min are effective

raw data

smoothed data

calculated peak start

calculated peak end

calculated baseline

Tc Elution and Peak Integration

Flow through solid scintillator detector

Automated Peak searchBaseline calculationSmoothIntegration

Determine net peak area countsNcts

Sample Processing-Separation-Detection

<12 minutes per sample!near real time4 samples plus one matrix spike addition per hour

Continuous operation demonstrated for 54 hours

Precision and accuracy demonstrated for variety of complex nuclear waste matrixes

34

Automated Tc Monitor SuccessesFully automated monitor including on-line sample preparation

Challenging selectivity issues addressed for highly radiological, complex, variable sample matrix

Technology suitable for on-site/at-line monitoring in harsh industrial environment

Automated Separation Laboratory Platform

Dissolution

Extraction Chromatography

Anion Exchange

Mass spectrometry

SEPARATION(S)Resolve interferences

Radiometric

Matrix Adjustment

Speciation Control

SAMPLE PREPARATION

DETECTION

Automated Separation Laboratory Platform

Extraction Chromatography

Anion Exchange

SEPARATION(S)Resolve interferences

Sequential Injection SeparationsTypically

Single column separationCoupled to detectionFluidic system

Laboratory AutomationSamples in parallelSeparate containers or columns - no carryoverWorkstationsSupports:

Radiometric detectionICP-MSTIMS

Automated Separations for Multiple Detection Methods

38

RadiometricICP-MSTIMS

TIMS:Very low detection limits, and precise isotopic ratiosCapable of measuring Pu at global fallout levels of ng / m2 from small mass samplesBut TIMS requires essentially pure sources

Multiple separation / purification steps in sequence, moving to smaller and smaller scales

Total SampleDissolution

Matrix Separations

Actinide Separations

SingleBead

Separations

MW-assistedDissolution

AutomatedColumn

Separations(Matrix)

AutomatedColumn

Separations(Actinides)

AcceleratedSingle Bead

Uptake

Extraction Chromatography

AnionExchange

Workstations Concepts for Sample Prep…Flexible approach applicable to various analytical challenges

Column conditionSample load and wash

Uranium elute Thorium

elutePlutonium elute

Classic Actinide Anion Exchange Separations

Am U Th Pu/Np7.2M HNO3 9M HCl 1.2M HCl

Pu-containing fraction

Matrix removalvia precipitations

Matrix Separation for ActinidesLoad sample on stacked TEVA and DGA columnsSeparate and recover actinides of interest from TEVA column

Pu/Np

Stacked columns

TEVAonly

DGAonly

Recovery and separation from soil

digestate matrix in 7.5 M HNO3

EC as matrix separation prior to Anion Exchange (AnIX)

ClassicPrecipitations

ppt contains:Precipitant.Am, LnsThPu/Np

AnIX

EC:TEVA-resin

eluent contains:....Pu/Np

AnIX

load load

AnIX

load

No separation

sample contains:MatrixUAm, LnsThPu/Np

Column-based separations suitable for automation

Manual Separation Sequence for TIMS Manual EC on Vacuum Box

ECColumn

1. Wet Ash

2. Redox Adjust

AnIXColumn

Source Preparation

AcidSample(SPIKE)

TIMS

EC (TEVA) 97 ± 3%

400 µL AnIX 89 ± 3%

Overall efficiency(244Pu)

2.7 ± 0.3%Compares to 2.78 ± 0.85%

for process using precipitations

Grate J.W.; M.J. O'Hara; A.F. Farawila; M. Douglas; M.M. Haney; S.L. Peterson; T.C. Maiti; C.L. Aardahl. "Extraction Chromatographic Methods in the Sample Preparation Sequence for Thermal Ionization Mass Spectrometric Analysis of Plutonium Isotopes",Analytical Chemistry 2011, 83, 9086-9091. ; DOI: 10.1021/ac202150v

Matrix Free

2.5 fg Pu spikes

Pu-244 Pu-242 Pu-239

EC chemical recovery at very low levels is effectiveAnIX separation downstream unimpairedTIMS bead loading and ionization efficiency unimpairedEC with wet ash compatible with TIMS detection process

Challenges for Automating Column-based Separations in Radiochemistry

Strong acid solutions2 mL column bed scale

larger than typical bioanalytical applications.Cross contamination must be preventedCustomization (no COTS fits needs)Complexity/Reliability

44

Customize Commercial Liquid HandlerX-y-z robotics

Design from scratchFluid transport via tubing

y-z fraction collector

Column Separation Automation Platforms

Customized to match actinide anion exchange process very closely

SLOWDrifting Positional Accuracy

PNX-II System (Pacific Northwest eXtraction system)

Disposables in Blue

Designed for varying column configurationsOverhead rack is adaptable to a variety of column types

2cc Column

0.1cc Column

StackedCartridges

2cc Cartridge

Sample routed manually via disposable components (side);Separation agents delivered from the top

Custom fraction collector fabricated at PNNL

Actuation with fixed stops, feedback confirms each step

2 translational directions (only 2!)

2 barriers to prevent cross-column contamination

Parts easily removed and cleaned

Waste trough and 5 vial positions

PNX-II System (Pacific Northwest eXtraction system)

X-contamination verification w/ ~37 kBq Pu-238 resulted in < MDA in vials and surface smears

Automated Separations on PNX-IIExtraction Chromatography and Anion Exchange

Demonstrations at radiotracer levels

Demonstrations at mass spectrometry levels

Chemical recoveriesOverall measurement efficiency Isotopic ratios in Standard Reference Materials

EC on PNX-II at TIMS levels

EC 85%

Chemical Yields,* Pu

2 mL AnIX 88%

*Avg of 6 samples3 digestate matrix (86.4%)3 acid – matrix free (83.7%)

TEVA

ECcolumn

2 mLAnIX

column

0.1 mLAnIX

column

transp/redox Adj**

source prep

TIMS

sample

244Pu242Pu

244Pu 242Pu 239Pu

tripletrans-pose

EC only on PNX-II

wet ash

Spiked Clean Soil Digestate– Spiked Known

239Pu

AnIX on PNX-II at TIMS levels

ppt – 2 mL AnIX 81%

Chemical Yields,* Pu

0.1 mL AnIX 84%

*Avg of 6 samples3 digestate matrix (80.8%)3 acid – matrix free (81.3%)

2 mL AnIX only on PNX-II

pptdissolveIn nitric*

2 mLAnIX

column

0.1 mLAnIX

column

source prep

sample

244Pu 242Pu 239Pu

trans-pose

Spiked Clean Soil Digestate– Spiked Known

TIMS244Pu 242Pu 239Pu

Laboratory Automation ApproachWorkstation Toolkit for Actinide Analysis

Method developmentAutomated workstationsLink workstations with

manual transfers

DissolutionAutomated

ColumnSeparations

(Matrix)

AutomatedColumn

Separations(Actinides)

AcceleratedSingle Bead

Uptake

Extraction Chromatography

AnionExchange

Sensors and Systems for Radionuclides in Water Preconcentrate and Detect

Automated Fluidic SystemCapture on a columnElute to downstream detector

Sr-90Beta emitterSr2+

SuperLig 620

Radionuclide SensorCapture on a columnDetect on the column

Tc-99Beta emitterTcO4

- (pertechnetate)Anion exchange

Anion Exchange beads &Scintillating beads mixed in a Column packing

Tc Sensing: Random Order

0

2

10

1

5 dpm

Tc-99 in Hanford Groundwater, dpm

Radionuclide Monitors on Hanford SiteTc-99 as TcO4-

Hanford groundwater Pump and Treat Plant

Outdoor groundwater well Near Columbia River

Sr-90 in ground water

Articles, Chapters, and ReviewsFall 2012

Ch18 Automated Radiochemical

Sensing Separation and Analysis

2009

Acknowledgements

DOE - National Nuclear Security Administration

Office of Nonproliferation Research and Development NA-22

U.S. Department of Energy Environmental Remediation Science ProgramEnvironmental Management Science Program

Hanford site contractors

Matthew O’HaraKaren NoyesOleg B. EgorovTravis MintonMatt DouglasSteve PetersenTapas Maiti Diana BellofattoCrystal RutherfordSamuel MorrisonBrian DockendorfAnne FarawilaStan OwsleyJohn Wacker

Extras

Microchemical Separation and Bead Source Preparation

TypicalSlow static diffusion

NewNoncontact mixing by acoustic streaming

CHALLENGESVery small volumesDiffusional limitationsReynolds number contraintsAvoid sample contamination

0 min

30 min0 min 60 min

5 min 10 min

Diffusion only:

Acoustic streaming (82 MHz/25 dB):30 min 60 min

Acoustic Streaming Results

Uptake with streaming is ~10 times faster than diffusion alone!

sorption of a strong trianionic dye, amaranth (5.510–5 M), by ~760 µm strong anion exchange resin beads

1 mm

no streaming

w/streaming

Direct comparison after 1 hour

“Big bead” in microwellsPu uptake from 7.5 M HNO3

Acceleration:5x faster uptake

Platform for Parallel Single Bead Procedures

96 transducers 384 microwell plate

Enhanced platform for parallel single bead procedures

96 piezoelectric transducers excited w/ radiofrequency powerCapable of uniform mixing across 384 microwell plate

Produces a rotating lateral vortex

DissolutionAcid digestion in beakers on hot plates

Microwave-assisted total sample dissolution in acids12 samples in parallel

Instant on, instant offProgrammable heating

Feedback on temperature and pressureANALYTICAL CHALLENGESTotal sample dissolution of soil/sediment Recovery of Pu, including refractory Pu Safety

3-Step Method1. HNO3 / HCl / HF dissolution2. Matrix reduction by evaporation

Drives off Si as SiF43. HNO3 / H3BO3 *

Dissolve metal fluoridesScavenge free F-

Pu recovery demonstrated in further experiments

Dissolution demonstrated in diverse sediments

> 99.9%

Plutonium Recovery

Sediments spiked with Pu tracers

MAPEP standards containing leachable and refractory Pu as separate isotopes

Pu determinations in standard reference soils using TIMS

Side-by-side comparisons with hot plate digestions

Acceleration:Reduce time by ca. 50% compared to hot plate beaker methods12 sample in parallel

AutomationHeating is instant on, instant off,under preprogrammed controlwith feedback