Standard less analysis

Quantitative Standard-less XRF AnalysisAXAA ConferenceNewcastle 2002: 

Quantitative Standard-less XRF Analysis AXAA Conference Newcastle 2002 Stanislav Ulitzka Twotheta Pty Ltd Sydney

Quantitative Standard-less XRF Analysis: 

Quantitative Standard-less XRF Analysis Quantitative vs. Semi-quantitative Standard-less Round robin test

Standard-less … WHY?: 

Standard-less … WHY? Varying sample types Solid, liquid, loose powders, scales, drillings … Sample shapes Flat, odd, small quantities or pieces, thin layers … “Unusual” elements (Be, B, C, N, O) - Fluorine to Uranium

Methods: 

Methods “Peak hopping” better counting statistics Scanning possibility of very fast scanning (3 to 5 min) Fine-tuning and sub-sets possible with own standards (steel, alloys etc.)

“Peak hopping” vs. Scanning: 

“Peak hopping” vs. Scanning

Counting Statistics: 

Counting Statistics th = sqrt ( R * t ) R = counts/s t = counting time CSE rel [%] = 100 / sqrt (R * t) Example: sqrt (1’000’000) = 1000  0.1 % relative error

Calibration!!!: 

Calibration!!! Standards single element/oxide or multi-element  intrinsic sensitivities Corrections Background Overlaps Matrix Drift, media, and film correction

Background correction: 

Background correction

Background correction: 

Background correction 66 kcps 23 kcps 12 kcps

Analysis of unknowns - ASMQ: 

Analysis of unknowns - ASMQ Tuned analytical recipe Select measurement Load analytical recipe Load sample parameters Automatic Search Match and Quantify

Analysis of unknowns: 

Analysis of unknowns Measurement - acquisition of intensities same method as for standards Manual check of BG correction & labelling of peaks (optional) Sample description – most important! Type – solid, liquid, bead, PP Flux/binder – chemistry, weights Normalisation Y/N?; balance compound? Unmeasured compounds – B2O3, LOI, CO2, organics …

Sample description – IQ+: 

Sample description – IQ+

Sample description - UQ: 

Sample description - UQ

Report – IQ+: 

Report – IQ+

Report - UQ: 

Report - UQ

Major elements – SY-2: 

Major elements – SY-2

Major elements – SY-3: 

Major elements – SY-3

Trace elements – SY-2: 

Trace elements – SY-2

Trace elements – SY-3: 

Trace elements – SY-3

Conclusions: 

Conclusions Any standardless method yields “numbers” Quality of analysis (accuracy) depends on Calibration Matrix correction (to a certain extent) Correct sample description/definition “Driver” training!!!