Radial, Axial or Dual View ICP: Which Do You Choose? Manny Almeida Teledyne Leeman Labs, Inc. Hudson, NH

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1 Radial, Axial or Dual View ICP: Which Do You Choose? Manny Almeida Teledyne Leeman Labs, Inc. Hudson, NH

2 Teledyne Leeman Labs, Inc. US based manufacturer of Elemental Analysis instruments Located in Hudson, NH Manufacturing elemental analyzers for 30 years Instruments Manufactured Hydra II and QuickTrace Series of Mercury Analyzers o Cold Vapor Atomic Absorption (CVAA) o Cold Vapor Atomic Fluorescence (CVAF) o Solid Mercury Analyzer (Hydra II C) Prodigy DC Arc o Elemental Analysis of Solid Samples Prodigy7 and Prodigy Series ICP-OES o Elemental Analysis of Liquid Samples

3 Teledyne Leeman Labs, Inc. Prodigy7 ICP Hydra and QuickTrace Mercury Analyzers Prodigy DC-Arc Prodigy ICP

4 Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) A multi-element technique that uses a high temperature plasma to excite atoms so they emit wavelength-specific photons of light, characteristic of each element. The number of photons produced is directly related to the concentration of that element in the sample ICPs consist of An Optical System RF Power Supply Sample Introduction System

5 Plasma Views Modern ICPs are available in three viewing configurations: Radial Axial Dual View Each view has advantages and disadvantages

6 Original ICP View Sometimes called Vertical or Side-On Plasma Accommodates all ICP matrices Detection Limits similar to Flame AA Better for Refractory Si, Ti, B, W, Mo Can analyze S, P and Halogens Radial ICP

7 Radial ICP Molecules (YO) Plasma Viewed Ions (Y + ) Atoms (Y)

8 Characteristics of Dedicated Radial Viewing Wide dynamic range Low to high concentrations Fewer dilutions compared to AA Excellent tolerance to dissolved solids 33% NaCl Excellent torch lifetimes Negligible Easily Ionized Element (EIE) effects Na affects K Radial detection limits

9 Sometimes called a Horizontal Plasma Useful analysis in many different sample matrices Excellent Detection Limits Has certain limitations Matrix Interferences Na and K can have problems The solution complicates sample preparation Axial ICP

10 Axial ICP Plasma Viewed Longer Path Length = Greater sensitivity

11 Why Axial ICP Works: Signal is proportional to the path length When viewing axially, the spectrometer observes only the central channel of the plasma (containing the analyte signal), blocking out the outer (high background) region This enhancement in signal-to-noise ratio provides 5-20x better improvement in detection limits. Signal measured here

12 Characteristics of Dedicated Axial Viewing ~10x better DLs than Radial Dynamic range shifts lower Less tolerant to dissolved solids than radial Torch lifetimes shorter than radial Torch longer than radial design Potential EIE effects

13 Dual View ICP Combines both Radial and Axial Views in one instrument Sensitivity of Axial ICP Better Detection Limits Sample Versatility of Radial ICP Freedom from matrix effects Provides Tremendous Comfort Factor The right view for any sample

14 Dual View

15 Dual View - Axial View Dual View Radial View Entrance to Instrument Plasma Source Mirror Mirror Torch

16 Dual View - Radial View Dual View Axial View Entrance to Instrument Plasma Source Mirror Mirror Torch

17 Dual View Radial length torch used

18 Characteristics of Dual View ~10x better DLs than radial Very wide dynamic range if using both views dynamic range shifts lower with axial view Tolerance to dissolved solids similar to that of dedicated axial Torch lifetimes shorter Torch longer than radial design Slots or hole to get radial view EIE effects of dedicated axial can be eliminated by using radial view of DV option Samples are only analyzed once Axial and radial view

19 Dynamic Range and Detection Limit

20 Which View Is Best for You? To decide which is the best fit for your application, the following questions need to be considered: What are your sample types? What are the concentration ranges in your samples? Do you need to determine any of the Alkali Elements?

21 Which View Is Best for You? What are your sample types? Aqueous Organic High Dissolved Solids Axial, Radial, Dual View Axial, Radial, Dual View Radial, Dual View

22 Which View Is Best for You? What are the concentration ranges in your samples? ppb ppm ppb- ppm ppm - % ppb - % Axial, Dual View Radial Axial, Dual View Radial Dual View

23 Which View Is Best for You? Do you need to determine any of the Alkali Elements? Li Na K Rb Cs No Axial, Radial Yes Radial, Dual View

24 Some Examples 25

25 Wear Metals in Oil What are your sample types? Organic What are the concentration ranges? ppm Alkali Elements? Yes Radial 26

26 Wear Metals in Oils typical results Measured Certificate % Recovery Ag Al B Ba Ca Cd Cr Cu Fe K Mg Mn Measured Certificate % Recovery Mo Na Ni P Pb Sb Si Sn Ti V Zn

27 Soils (6010c) What are your sample types? Aqueous What are the concentration ranges? ppb - % Alkali Elements? Yes Dual View 28

28 NIST 2709 San Joaquin Element Concentration Found, mg/kg RSD Median Value, mg/kg Range, mg/kg As <20 Ba Cd <1 Co Cr Cu Mn Ni Pb Sb <10 Se ND V Zn Al 2.75 % Ca 1.61 % Fe 2.72 % K % Mg 1.35 % Na 0.076%

29 Wastewater (200.7) What are your sample types? Aqueous What are the concentration ranges? ppb - ppm Alkali Elements? Yes Dual View 30

30 Wastewater (200.7) NIST 1640a NIST 1640a Element Measured Conc (µg/l) Certified Conc (µg/l) %Rec Eleme nt Measured Conc (µg/l) Certified Conc (µg/l) %Rec Ag Al As B Ba Be Ca N/A --- Cd Co Cr Cu Fe K N/A --- Li 2.43 N/A --- Mg N/A --- Mn Mo Na N/A --- Ni P <MDL N/A --- Pb Sb Se Si N/A --- Sn <MDL N/A --- Sr Ti <MDL N/A --- Tl --- <MDL --- V Zn

31 Wastewater (200.7) What are your sample types? Aqueous What are the concentration ranges? ppm Alkali Elements? Yes Radial 32

32 Wastewater (200.7) ELEMENT FOUND (µg/l) CERTIFIED (µg/l) ELEMENT Ag Al As B Ba Be Cd Co Cr Cu Fe Mn Mo Ni Pb Sb Se Sr Tl V Zn

33 Conclusion One view type doesn t fit all applications Look at advantages and disadvantage of each configuration Level of operator expertise To determine the one right for your application consider: Sample type Concentration ranges Elements determined