Common Challenges facing Laboratories doing Elemental Analysis Today

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2 Common Challenges facing Laboratories doing Elemental Analysis Today Increased need for multi-element determination over a wide dynamic range Desire to reduce the overall cost of analysis due to rising costs (instrument supplies and consumables power, labor, etc) Difficulty in sourcing some gases especially in remote areas and emerging geographies Availability of suitably trained personnel to develop methods, perform sample measurement and interpret results Some laboratories under pressure to improve safety by removing flammable gases Page 2

3 NEW Agilent 4100 Microwave Plasma-Atomic Emission Spectrometer (MP-AES) New technique for elemental determination using atomic emission o o o o Microwave excited plasma source Nitrogen based plasma - runs on air (using a N 2 generator) Improved performance compared with flame AA Higher sample throughput with fast sequential measurement More than 2x faster than conventional flame AA Superior detection limits and improved dynamic range Easy to use New generation software featuring automated optimization and software applets that load a preset method One piece torch with easy torch removal and replacement no alignment Reduced operating costs Runs on air eliminates need for Acetylene, Nitrous Oxide, Argon, etc. Eliminates need for source / hollow cathode lamps Simple installation no chiller, 10 A supply Improved Safety Eliminates need for flammable gases and cylinder handling Safe, reliable unattended multi-element overnight operation Page 3

4 Microwave Plasma Emission Overview Ground State Excited State Emission Monochromator & Detector Quantitation Microwave excited Plasma Sample Page 4

5 How Does MP-AES Work? Agilent s patented microwave waveguide technology Using nitrogen as the plasma gas (a diatomic gas) gives a robust plasma with a conventional torch. Nitrogen can be supplied either via bottled gas or nitrogen generator Magnetic excitation gives a toroidal plasma and an effective central zone for sample injection The microwave magnetically excited nitrogen plasma Provides a robust, high temperature source in conventional torches (approx K) A cooler central channel suitable for sample atomization Creates high intensity atomization emission lines Page 5

6 Page 6 Stability Over 4 Hours % RSD

7 Performance Comparison Typical Detection Limits DL s in ppb, clean water samples Element Flame AA MP-AES K Ca Mg Na Au Pt Pd Ag Rh sigma DLs using a 10 second integration time with dewar nitrogen Page 7

8 Performance Comparison Typical Detection Limits DL s in ppb, clean water samples Element Flame AA MP-AES As* Cd Cr Mn Pb Sb Se* Zn * 30 second integration time used for these elements 3 sigma DLs using a 10 second integration time with dewar nitrogen Page 8

9 Au Extended Calibration Range MP - Normal AA range MP - Extended Range Page 9

10 Page 10 Simple Torch Installation No Alignment

11 New Generation MP Expert Software Windows 7, worksheet based software Fresh, clean look Provides capability for applet style operation using preset methods, or access to full capabilities Innovative and simple to use background correction Automated optimization tools Page 11

12 New Generation MP Expert Software Retains familiar worksheet based approach Spectra Results matrix Calibration Replicate data Page 12

13 Typical Instrument Operating Parameters Instrument Parameter Setting Nebulizer pressure Pump speed Pump tubing Integration time No. of replicates 3 Sample uptake delay Stabilization time Fast Pump during Uptake Viewing position Sampling mode Background correction kpa (optimize per element) 15 rpm White-white (sample) Blue-blue (waste) 3-5 sec for most samples; sec at DL levels 15 sec (typical) 10 sec On (80 rpm) -10 to +10 (optimize per element) Manual or Auto sampling Auto or FLIC Page 13

14 Schematic Diagram Instrument exhaust 2. Pre-optics window 3. Torch loader 4. Peristaltic pump 5. Plasma enable button 6. High voltage power supply 7. Electronics (control PWB) 8. Pre-optics 9. Plasma (Magnetron) 10. Monochromator with CCD detector 11. External gas control module 12. Cooling air inlet 13. Inlet gas connections Page 14

15 Optical Diagram Detector Pre-optics Monochromator Cassette style Torch Page 15

16 Accessory Options for the 4100 MP-AES Automate and simplify analysis with the SPS3 autosampler (required for unattended overnight operation) For organic applications, use the EGCM to bleed air into the plasma minimizing C build-up and reducing background also requires the OneNeb inert nebulizer (included with the Organics kit) For low ppb level detection of As, Se or Hg, use the Multimode Sample Introduction System (MSIS) also requires the 5 channel peristaltic pump option Page 16

17 Technique Comparison: MP-AES and Flame AA Feature MP-AES Flame AA Detection Limits Linear Dynamic Range Flammable Gas Oxidizing Gas Fuel gas CO 2 Light sources Drift correction Overnight unattended Running costs High solids Better Better Not Required Not Required Not Required Not required Not required Yes Lowest Good Good Good Acetylene Nitrous oxide 1 6 tonnes p.a. HC and D2 lamps Double beam No High Good Page 17

18 Reduced Cost of Ownership Assumes measuring 9 elements (4 nitrous-oxide elements) in batches of 100 samples, 3 days/week using the N 2 generator. Page 18

19 Newmont's Carlin Lab AA Consumable Costs vs MP-AES* * Acknowledgement John Borland, Newmont Mining Corporation Page 19

20 Key Customer Benefits Higher Performance Ideal flame AA alternative Handles major, minor & most trace levels Matrix handling to match flame AA Lower Cost of Ownership Runs on air Multi-element unattended operation Moderate sample throughput Faster Measurement & Easy Operation Fast sequential measurement Simultaneous background correction New generation software Plug & Play torch Safer Laboratory Operation No flammable gases Unattended multielement operation Page 20

21 Page 21 Market Application Examples

22 Key Benefits by Market Chemical / Petrochem Improved performance Matrix handing to match flame AA Low running costs Ease of use Food and Agriculture Fast sequential measurement Ease of use Improved performance No flammable gases Environmental (non regulated methods) Improved performance Runs on air Unattended operation Geochemistry/ Metals Runs on air Improved performance No flammable gases Unattended operation Moderate pricing Page 22

23 Developed Application Notes Geochemical New methodology for analysis of gold and precious metals Analysis of base metals in geochemical samples Chemical & Petrochemical Analysis of wear metals and contaminants in engine oils Analysis of lubricating oil additives Analysis of trace elements in petroleum and diesel fuels Food & Agriculture Analysis of soil extracts Cost-effective analysis of major, minor, and trace elements in foodstuffs Environmental Determination of metals in industrial wastewaters Page 23

24 Environmental Applications WEEE/RoHS Compliance Metals in Soil and Sediment Waste Water Analysis Page 24

25 European EN71 Part 3 Requirements EN 71 Part 3 (1998) defines requirements for testing the migration of inorganic elements These standards have also been adopted in many countries outside the European Community Maximum acceptable element migration from toys in mg/kg of toy material under EN 71 Part 3 25 Page 25

26 Certified Reference Materials EC 681 : European Reference Material ERM-EC 681 Polyethylene, from Institute for Reference Materials and Measurements (IRMM), Belgium. NMIJ 8102a : Certified Reference Material 8102a ABS Resin, from National Metrology Institute of Japan (NMIJ). Page 26

27 Achieved Recoveries for CRMs Cadmium EC 681 NMIJ 8102a Digestion Method Measured (mg/kg) Certified (mg/kg) Measured (mg/kg) Certified (mg/kg) EN ± ± ± ± 0.2 HNO 3 /H2O ± ± ± ± 0.2 Chromium EC 681 NMIJ 8102a Digestion Method Measured (mg/kg) Certified (mg/kg) Measured (mg/kg) Certified (mg/kg) EN ± ± ± ± 0.35 HNO 3 /H2O ± ± ± ± 0.35 Lead EC 681 NMIJ 8102a Digestion Method Measured (mg/kg) Certified (mg/kg) Measured (mg/kg) Certified (mg/kg) EN ± ± ± ± 0.89 HNO 3 /H2O ± ± ± ± 0.89 Page 27

28 Geochemical, Metals and Mining Applications Elements in Geological Samples High Purity Gold Analysis Metals in Ore Metals in Plating Bath Solutions Page 28

29 Gold and Precious Metals by Fire Assay Au, Pt and Pd extracted into a silver sphere Dry and Crush Fire Assay Process Dissolve in 4mL 25% AR Page 29

30 Traditional Off-Peak Correction for Ag in Digest Limitations with Off-Peak Correction Correction points must be set manually Susceptible to spectral interferences Is this the best correction point for this matrix? Page 30

31 Better Alternative - Use Auto Correction Auto background correction uses the spectrum around the peak of interest to create: 1. Models of the background (the blank) and the analyte (the standards) these are created during calibration 2. For every sample the amount of blank model and the amount of analyte model in the spectrum is calculated 3. Once the amount of analyte is known, the corrected concentration can be determined Page 31

32 Auto Correction for Ag in Digest Accurate model of the sloping background from the partial peak overlap Blank Spectrum Standard Spectrum Page 32

33 Auto Correction Improves Detection Limits Element Wavelength (nm) DL with Auto Correction (ppb) DL with Off-Peak Correction (ppb) Ag Zn Mn Mn Cu K As And it s easier to use! No method development No correction points to select Page 33

34 Accuracy Gold in Custom CRMs* CRM Certified value (mg/l) MP-AES result (mg/l) * These custom CRMs were professionally prepared from solid ore samples and certified through a round robin test process Page 34

35 Accuracy Platinum & Palladium in Custom CRMs Platinum CRM Certified value (mg/l) MP-AES result (mg/l) Palladium CRM Certified value (mg/l) MP-AES result (mg/l) Page 35

36 For Challenging Applications OneNeb Nebulizer Robust PFA and PEEK construction Inert - resistant to strong acids such as HF Resistant to breakage Molded plastic design provides improved nebulizer to nebulizer reproducibility Constant diameter narrow bore tubing through to nebulizer tip Ideal for high solids/particulates Improved tolerance to high TDS samples Narrow aerosol size distribution provides improved precision Handles a wide flow range from 0.1 to 2 ml/min. No sensitivity loss at low flow rates Page 36

37 Proportion of Total Principle of Operation Inert OneNeb Nebulizer Tip geometry dimensioned to allow carrier gas to mix with the sample Turbulent mixing of liquid and gas occurs Produces aerosol with a narrow size distribution range Droplets mixed into gas flow No area of low pressure Unique Flow Blurring action increases nebulization efficiency Greater efficiency than conventional concentric nebulizer Improved sensitivity Inert OneNeb nebulizer Conventional concentric nebulizer Droplet Size (mm) Page 37

38 Performance Proof OneNeb Outperforms Conventional Nebulizers Geochemical application Measuring trace Au in cyanide leach (0.3% CN, 0.8% NaOH) Run with standard sample introduction system Blockage of the sample introduction occurs within 4 hours Tip of the concentric nebulizer blocked! Tip of the OneNeb nebulizer after 37 hours of operation! Still working perfectly! Application note available Evaluation of a novel nebulizer using ICP-OES Page 38

39 Chemical and Petrochemical Applications Additives in Lubricating Oil Wear Metals in Used Motor Oil Metals in Gasoline and Diesel Fuel Metals in Polymers Page 39

40 Organics - External Gas Control Module (EGCM) 1. Prevents carbon build up on the injector when running organics 2. Reduces the background emissions from the plasma 3. A controlled flow of air is bled into the Auxiliary gas flow through the torch Page 40

41 Solvent Background - Minimized with EGCM Page 41

42 Solvent Background - Minimized with EGCM Page 42

43 Instrument Parameters Parameter Setting Nebulizer Inert OneNeb Spray chamber Double-pass glass cyclonic Sample tubing Orange/green solvent resistant Waste tubing Blue/blue solvent resistant Read Time 3 s Replicates 3 Stabilization time 15 s Rinse time 45 s Fast Pump (80 rpm) On Background correction Auto Pump speed 5 rpm Page 43

44 Standard and Sample Preparation Wear metals and contaminants 1:10 dilution with Shellsol Additives 1:100 dilution with Shellsol Standards Prepared from 500 ppm S21 (Conostan) All matrix matched with blank oil for constant viscosity Page 44

45 Measured Results for SRM 1085b Wear Metals Great recoveries for all key elements Page 45

46 Measured Recoveries on 10 ppm Spike of Gear Oil Great recoveries for all key elements Page 46

47 Measured Results for Additive Elements Measured Results vs Certified Values Element Measured (mg/kg) Certified (mg/kg) Recovery % P ± ± Zn ± ± Mg ± ± Ca ± Ba ± ± Measured Recoveries on 10 ppm Spike of Gear Oil Element Mixed Gear (ppm) Spike (ppm) Recovery % P Zn Mg Ca Ba Page 47

48 Normalized Conc Organics Long Term Stability :00 01:00 02:00 03:00 04:00 05:00 06:00 07:00 08:00 Time (h:mm) Zn nm Si nm Fe nm Ni nm Ag nm Pb nm Cu nm Mg nm Ti nm Al nm 10 ppm S21. All lines show precision <1% RSD. Page 48

49 Food and Agricultural Applications Food Product Labeling Food Quality Environmental Contaminants Soil Fertility and Salinity Studies Page 49

50 Which Elements are Monitored in Foods? Toxic trace elements Low level analysis typically ppb levels As, Cd, Hg, Pb, Tl, Cr Common elements that are toxic in excess Typically range from ppb to ppm level Al, Ni, Cu, Zn, Se, Mo, Sn Essential minerals Can cover a wide range from ppm to % levels Na, Mg, P, S, K, Ca, Fe Page 50

51 Measured Results for CRM Food Samples NIES No. 10c Rice Flour High Purity Stds CRM Wheat Flour * Reference values only Page 51

52 Certified (mg/kg) Certified (mg/kg) Certified (mg/kg) Certified (mg/kg) Wide Dynamic Range Magnesium (r = ) Phosphorus (r = ) Measured (mg/kg) Measured (mg/kg) Calcium (r = ) Potassium (r = ) Measured (mg/kg) Measured (mg/kg) Page 52

53 Which Elements are Monitored in Soils? Environmental contaminants Identify and quantify soil contaminants from effluent or emissions As, Cd, Hg, Pb, Tl, Cr Soil salinity studies Study effects of major cations Ca, Mg, Na, K and Al Soil fertility studies Measure essential nutrient levels both trace and minor levels Co & Mo for N 2 fixation or P for plant growth Page 53

54 Background and Interference Correction Analyte Wavelength (nm) Background Correction Al Auto As FLIC Cr Auto Cu Auto Fe Auto Mn Auto Ni Auto Pb Auto Zn Auto Page 54

55 Fast Linear Interference Correction (FLIC) FLIC uses models of the blank, standard and potential interferent elements to correct for spectral interferences Page 55

56 FLIC Performance Example Fe Interference on As As concentration in the presence of 1,000 ppm Fe is <IDL when using FLIC Using Auto Using FLIC Page 56

57 Measured Results for NIST SRM 2711 Montana Soil Analyte MP-AES Results NIST Reference Average (mg/kg) Range (mg/kg) Al ± As 90 ± Cr 21 ± Cu 90 ± Fe ± Mn 600 ± Ni 17 ± Pb 1400 ± Zn 300 ± Page 57

58 Accessory Options for the 4100 MP-AES Automate and simplify analysis with the SPS3 autosampler (required for unattended overnight operation) For organic applications, use the EGCM to bleed air into the plasma minimizing C build-up and reducing background also requires the OneNeb inert nebulizer (incl. with the Organics kit) To enable low ppb level detection of As, Se or Hg, use the Multimode Sample Introduction System (MSIS) also requires the 5 channel peristaltic pump option Page 58

59 Improving Detection Limits for As, Se and Hg with MSIS Analyte Conventional Nebulization mg/l MSIS in Simultaneous Mode mg/l As Se Hg Page 59

60 Comments from Early Adaptor Seed Sites Newmont Mining Corporation, USA With the MP-AES instrument Agilent seems to have hit a homerun for both gold analysis and base metal analysis. It provides superior detection limits and vastly expanded calibration range this enables quick easy analysis at trace levels as well as eliminates the need for time consuming dilutions of higher grade samples. All of this at an affordable price of well below that of ICP and only slightly higher than top of the line AA units. Bobby Joe Reichel Newmont Mining Corporation Sachsenforst, Germany The results for our aqua regia soil extract samples are convincing, and those results are in very good agreement with the round robin, which was performed Europe wide on those samples. Frank Symossek Sachsenforst CERA Laboratory, India We are using MP-AES instrument for last couple of months, and we found instrument is best to detect trace metals compare to AAS. In AAS sensitivity for B and P is very poor and fuel cost is very high, whereas using the MP-AES, sensitivity is very, very good and fuel cost is very low. In AAS, with elements like Al, Ca, Mo,Ti, V, Si etc, it consumes high quantities of Acetylene and Nitrous Oxide gas, and is very tricky - whereas using the MP-AES, it is very easy to detect. There is also no need to change Hollow Cathode Lamps which is time consuming and costly. S.S. Mhatre CERA Laboratory Page 60

61 Page 61 Agilent 4100 MP-AES

62 Dedicated MP-AES Microsite: Page 62

63 Questions? Agilent MP-AES The Market Leaders in Atomic Spectroscopy Page 63