Innovations In Optics. Zaheer Juddy - AIMS

Transcription

1 Innovations In Optics Zaheer Juddy - AIMS

2 POWER OF OPTICS

3 POWER OF OPTICS Conventional Measurement Techniques is Leaning towards OPTICS POWER OF OPTICS have given us a wide range of Entries to meet Modern World Quests - Bio-Medical Achievements (Non-Invasive Diagnostics..) - SPACE Research Applications (James Webb Space Telescope) - Defense & Forensic (Image Processing, AI, Neural Networks ) - Thermal Imaging for Industrial Diagnostics (Temperature Profile, Flow Profile, Leak determination)

4 Infrared Vibration & Rotation Stretching and bending of the bonds within molecules occurs at a frequency that is specific to that particular bond. If the vibration causes a change in dipole of the molecule then light at a particular frequency in the infrared band will be absorbed Symmetrical stretching Antisymmetrical stretching Scissoring Rocking Wagging Twisting

5 Wavelength, Wavenumber and Energy Wavelength c / f Wavenumber x micron = 10,000 / x cm 1 y cm 1 = 10,000/ y micron Energy /frequency Energy /wavelength E h* f E h*c/ With c= speed of light in m/s, f = frequency in Hz h = Planck s constant All parameters considered in vacuum

6 Electro Magnetic Spectrum Effect Electron excitation Electron transition Molecular vibration Molecular rotation Wavelength λ μm ,000 wavenumber й cm ,0000 1, Spectral regions : X-ray Ultraviolet Visible Infrared Microwave x micron = 10,000 / x cm 1 y cm 1 = 10,000/ y micron 1000 nm (nano meter) = I micro meter μm Analysis Band Laser Near-IR Middle-IR Far-IR Wavelength λ μm The near and mid infrared regions are suited for hydrocarbon liquid and gas analysis. Absorptions are stronger in the mid IR, but near Infrared is often used and can be favoured where it allows more robust materials and can determine properties of liquids and gases using chemometric modelling techniques Proprietary info goes here

7 Source Intensity Sample Detector IR is heat X-Y absorb Wavelength Absorbance Spectrum Transmittance Spectrum Intensity 100% Actionable Information! Wavelength Wavelength Wavelength 8

8 THE BEER LAMBERT LAW In optics, the Beer Lambert law, also known as Beer's law or the Lambert Beer law or the Beer Lambert Bouguer law (named after August Beer, Johann Heinrich Lambert, and Pierre Bouguer) relates the absorption of light to the properties of the material through which the light is travelling If T is transmission and I and Io are the intensities of light in and out of the gas then Therefore Absorbance A is T is transmittance, A is absorption l is path length,c is concentration N is number of molecules so degree of absorption is proportional to concentration (and pathlength!) N

9 TECHNOLOGY SURROUNDS US. WAKE UP!...

10 TFS Tunable Filter Spectroscopy Optical GC : Speciation without Separation The industry seeks a complementary (or alternative) to GC to Gas Chromatographs (consumables, cost, response time, complexity, safety) to NDIR type instruments (multi-component, linearity, stability) to traditional Wobbe meters (lack of speciation) to Calorimeters & Residual Oxygen style instruments (cost, fuel gas required, size)

11 Distinct Advantages & Features First principle measurement (PATENT DESIGN) Fast one second response No carrier gas/fuel gas required No periodic/ on-site calibration required Hydrocarbon Compositions in real-time with 0.05% repeatability, 0.1% accuracy No consumables (IR 1.5years) Low power DC operation (AC available) No instrument air required BTU, Wobbe index and density outputs Minimal sample conditioning required Linear response throughout range Pressure and temperature compensated No interferences Remote & completely unattended operation Easy Installation & Less Maintanance

12 TFS Tunable Filter Spectroscopy Measurement in based on NIR/IR absorption spectroscopy with advanced spectral decomposition analysis Example absorption spectra, C1 C3 alkanes 200nm (UV) through 10um (mid-ir) capable platform

13 TFS (Optical Gas Chromatograph) Overlapping spectra Resolution of the spectrometer Presence of non-linear behaviors Peak shifts & other feature modification behaviors Non-additive characteristics Due to real-world conditions x 10-7 Linear chemometrics won t work robustly Methane Ethane Propane N-Butane Iso-Butane

14 TFS Sensor Wavelength Scanning Technology Focused on relevant band(s) Wavelength scanning within the band(s) x THC 2 H 2 O CO CO

15 TFS vs. GC (Simplicity vs. Complexity) GC Oven, Columns, Valves, Fitting, Detectors, Carrier, Fuel Gas, Air etc.

16 GC MAINTENANCE EXPENSES PER YEAR

17 BTU Hydrocarbon Composition Monitoring

18 Tunable Diode Laser Spectrometry Why Tunable Diode Laser Spectroscopy? Sample cell GRIN Lens Mirror Laser Diode Beam Splitter Photodiode Reference Cell GRIN Lens Temperature Control Current Control Photodiode ELectronics Unit Non-contact measurement technique No sensor aging calibration concerns No consumables Advantage for applications with high levels of water vapor Lasers last many years before replacement is needed Low cost of ownership No interferences Extremely narrow emission line widths reduce interferences from other species

19 Key feature of TDLAS: Line-Lock Line Locking under Laser Temperature of C. Reference and Sample Spectra By adjusting the TEC temperature, the analyzer will tune the laser to emit a specific frequency that would be absorbed by the analytes. check the peak ( line ) in the spectrum. The peak ( line ) is locked if its index is at a certain position in the spectrum, varying by a line-lock window F Signal C 26.8 C 25.5 C C C 2F Signal Spectral Index Spectral Index

20 High performance gas monitor specially designed for measurement of very low gas concentrations Measurement of contaminants in natural gas Low ppm H2S measurement in process gases ppm NOx measurement for emission control

21 Quantitation by VUV Spectroscopy Science in a new light

22 VUV = Vacuum Ultraviolet

23 How VGA Gas Chromatography Detectors Work

24 Features of VUV Spectroscopy Vacuum Ultraviolet (VUV) Absorption from 120nm to 240nm A new and unique orthogonal separation Enables powerful detection capabilities Unique selectivity Unambiguous compound identification Easily deconvolve co-eluting analytes Clear and easy isomer differentiation Excellent sensitivity Low picogram Non-destructive analysis No ionization required Excellent temporal resolution Up to 100Hz Sampling Predictable linear response 1 st principle detection reduces calibration burdens Reliable & Easy to use No vacuums pumps

25 VUV Absorption Data is 3D

26 Library Search and Unambiguous Compound Identification Spectra are very robust; No ghost components in the library match list

27 Isomer Identification Many isomers have unique absorption spectra napthol OH (mainlib) 1-Naphthalenol napthol HO (mainlib) 2-Naphthalenol Chiral compounds (i.e. optical isomers) are the exception

28 Isomer Identification Mass Spectrometry Analysis of Xylene Isomers VUV absorbance provides unambiguous identification of xylene isomers 100 o-xylene (mainlib) o-xylene 100 p-xylene (mainlib) p-xylene 100 m-xylene (mainlib) Benzene, 1,3-dimethyl-

29 Spectra Can be Similar But Are Distinct Visual similarities are easily distinguished in the fitting routine; minor differences are significant Very deep spectral library Robust across process conditions Independent of matrix No instrument dependency Small spectral differences are easily and reliably distinguished, causing large changes to the fit parameter.

30 Easy Spectral Quantitation by VUV Governed by Beer s Law: A = ϵbc A = absorbance ϵ = extinction coefficient (M -1.cm -1 ) b = pathlength (cm) C = molar concentration (mol.dm -3 ) Spectral peak area of an analyte depends on: Amount of analyte (the number of molecules or mass) Cross-section (ability of a molecule to absorb a photon) Total flow rate through the flow cell (residence time) Flow cell geometry (length and volume) Spectral quantitation is robust and repeatable Identity not dependent on retention time or baseline resolution Compound % Mass is directly proportional to sum of its absorbance No special integration tools required All fitting and quantitation is performed by the software VUV absorbance is an inherent property unique to every compound

31 Compound Identification through Spectral Fitting Chromato gram Residual Spectrum Time Slice Raw Spectrum Fit Spectrum The left-hand side shows two figures from VUV Analyze software. Each figure represents a time slice of the chromatogram, corresponding to its spectrum. In the spectral plot, the blue area represents the fit, while the green outline displays the raw spectrum from that time slice If the blue area matches the green outline then it is a good fit with compound-specific spectra in the VUV library.

32 Overcoming Saturation A Unique VUV Feature Saturated Saturated To compensate for saturation, the software sums the full wavelength range. The advantage of using the full wavelength is when the apex is saturated, other parts of the spectrum are used to identify and classify each compound Quantitates by summing all absorbance across the total number of scans Software interpolates missing saturated area when quantifying the analyte Net result is 5 6 orders of dynamic linear range

33 Automated Quantitation Using VUV Analyze Software Gasoline Analysis Example Chromatogram File Retention Marker File Library File RRF File Analysi s Param eters Analytes of Interest Breakdow n Carbon Number & Class Breakdown Chromatogram Display Residual Plot Real-time Spectral Fitting

34 VUV Automated Spectral Fitting Comparison of Quantitation Methodologies GC- GC- FID Unambiguous Identification and Quantitation Identification by retention time Compound identity and mass % uncertainty Painful manual integration Calibration dependent

35 Comparison of Quantitation Methodologies GC- VUV Automated Spectral Fitting Extracted Ion: Unresolve d Isomers GC- MS Difficult Isomer Differentiation: MS spectrum of phentermine MS spectrum of methamphetamine Unambiguous Identification and Quantitation NO Quantitation Total Ion: GC-MS Summary: Chromatographic resolution matters Calibration dependent Matrix effects inaccuracies Difficult isomer differentiation Analysis complexity: Quantitating from reference ion Occasional need for multidimensional analysis (MS/MS)

36 Verifying Compound Identify Through Spectral Fitting Sum absorbance and spectral fitting results Individual spectra collected separately (library compounds) The sum absorbance represents all absorbance responses over a defined time interval Identification can be achieved irrespective of chromatographic separation Software verifies analyte identity by comparing peak shapes to known library compounds A good fit leaves no residual fit data Identity confirmation enables accurate quantitation

37 Average Absorbance VUV chromatogram represents the sum of all absorbance responses collected between nm A compilation of individual wavelength chromatograms Absorbance signals can be easily pulled apart by VUV software No Baseline Resolution No Problem! Post-run spectral filter set at nm to visualize prominent 1,3,5-TMB peak Post-run spectral filter set at nm to visualize prominent 2,3- Dimethyloctane peak Chromatogram represents the sum of all absorbance peaks over VUV spectrum from nm Time (minutes) nm

38 Average Absorbance Normalized Absorbance Spectral Fitting for Co-Eluting Peak Identification Absorbance Contribution to Sum Absorbance Analyte Fit weight 1,3,5-Trimethylbenzene ,3-Dimethyloctane Individual Absorbance Profiles 2,3-Dimethyloctane 1,3,5-Trimethylbenzene Model Fit Agreement Wavelength (nm) Time (minutes) nm VUV software automatically fits selected analyte spectra Fit values indicate how well the model fits with

39 Average Absorbance Deconvolution Creates Individual Analyte Chromatograms Accurate co-elution quantitation Analyte Peak Area* 1,3,5-Trimethylbenzene ,3-Dimethyloctane Deconvolved absorbance peaks New chromatograms for each analyte Time (minutes) nm Area under the curve is the sum of the absorbance response over a defined time interval The sum of individual absorbance responses within the defined retention time window Software deconvolution pulls apart overlapping absorbance from analyte co-elution Not dependent on chromatographic baseline resolution A new chromatogram is created for each compound

40 (mainlib) o-xylene Spectral Deconvolution of m&p Xylene: Isomer Analysis Comparison Mass Spectrometry Analysis of Xylene Isomers GC-VUV Absorbance Analysis of Xylene Isomers 100 o-xylene p-xylene 91 Chromatogram showing co-elution of m- and p-xylene isomers (mainlib) p-xylene (mainlib) Benzene, 1,3-dimethyl- m-xylene VUV absorbance provides unambiguous identification of m- and p-xylene isomers

41 Spectral Deconvolution Example: The Co-Elution of m- & p-xylene Summary: Chromatographic separation of analytes not necessary due to spectral deconvolution Isomers have distinct spectral differences that can be distinguished by VUV library Solves problem of identical mass spectra Identification and quantitation of co-eluting analytes and compounds can be automated using VUV software

42 Average Absorbance Average Absorbance 0.10 Average Absorbance nm 0.08 Deconvolution Summary Select region of 0.10 interest 0.08 Zoomed-In Chromatogram Select co-elution event Post-run visualization of co-elution Time (minutes) Time (minutes) nm Time (min) Software provides accurate quantitation Analyte Peak Area* 1,3,5-Trimethylbenzene ,3-Dimethyloctane Software creates new chromatograms Software fits and identifies compounds

43 Average Absorbance Spectral Quantitation Recap 0.04 Chromatogram is 3D Chromatogram is Sum of VUV Absorbance Sum VUV absorbance from nm Deconvolution Resolves Co-Elution Visualization of Co-Eluting Analytes Time (minutes) nm Quantitation is Reproducible and Unambigu Summary: VUV absorbance data provides both chromatographic and spectral information Software fits spectra and integrates area under the curves Sum of all analyte absorbance within the defined retention time window Completely reproducible Not dependent on calibration No matrix effects Deconvolution resolves co-elution to individual chromatograms

44 RAMAN EFFECT DEFINED LASER L SAMPLE C vib C L Same Vibrational Modes as MID-IR Light Scattering Technology Whereas Infrared Is Absorption Different Selection Rules Than IR s S = L - vib Excellent Spectral Resolution Minimum Component Overlap Maximum Component Specificity

45 RAMAN INTENSITY RAMAN APPLICATION INTERPRETATION OF RAMAN SPECTRA Peak Frequency Shifts Yield Sample Composition Peak Intensities Yield Concentrations Chemometric Data Analysis for Sample Parameters Requires Laboratory Data FREQUENCY SHIFT (cm -1 )

46 RAMAN ANALYZER SYSTEM Compact, Fiber-Coupled, Diode-Laser Raman System Computer PC Windows Diode Laser NM f/2.0 Raman Spectrograph Excitation Fiber Sample CCD Fiber Optic Cable (5 300 m)

47 RAMAN vs. INFRARED RAMAN ADVANTAGES No Interference From H 2 O NIR Requires Sample Conditioner Insert Probe Directly Into Process Stream Multiplex Capable Resolution Provides Minimum Component Overlap Chemometric Models Transfer Easily NIR Model Transfer Difficult

48 ABSORBANCE UNITS RAMAN INTENSITY ISO-OCTANE TOLUENE BUTANE p-xylene BENZENE OLEFINS TOLUENE SPECTRAL COMPARISON INFRARED vs. RAMAN 2.0 NEAR-IR ABSORANCE SPECTRA OF FIVE UNLEADED GASOLINES 785 nm EXCITATION 1 MIN. INTEGRATION 1.6 Reference: Spectroscopy, 7(7) Sept WAVELENGTH (nm) 0 ETHYL-BENZENE o-xylene m-xylene FREQUENCY SHIFT (cm -1 )

49 INSENSITIVITY TO TEMPERATURE Temp = 0 C Temp = 23 C Temp = 48 C RON MON ROAD RVP IBP % % % FBP DRIV E E DENS BENZ AROM TVL OLEF

50 ON-LINE, MULTIPLEXED, FIBER- COUPLED RAMAN PROCESS ANALYZER RAMAN DATA COMPONENT STREAMS BLEND HEADERS CHEMOMETRIC MODELS Auto Select Unique Models For Each Channel / Blend RVP RON MON ROAD API IBP 10% 50% 90% FBP E200 E300 V/L AROMATICS OLEFINS SATURATES BENZENE TOLUENE MTBE DRIVEABILITY SULFUR

51 Intrinsically Safe In-Line Raman Probe LOW TEMP < 85 C Pressure < 550 psi Visual Flow Meter Pressure Gauge Flow Cell 316 SS Terminal Block Electronic Flow Meter Electronic Grab Sample Detector NEMA 4X Enclosure 304 SS (14 Gauge) Tubing 1/4 316 SS Flow Out Grab Sample Drain Flow In

52 High Temp < 250 C Intrinsically Safe Immersion Raman Probe Raman Probe

53 RAMAN SYSTEM Backup Laser Automatic Switching Assures Maximum Uptime Wavelength Tracking No Model Discontinuity Intensity Normalization Transfer Chemometric Model From One System To Another

54 Thank You