Utilizing NeSSI for Analytical Applications

1. Utilizing NeSSI for Analytical Applications Brian Marquardt Dave Veltkamp

2. New Sampling Sensor Initiative ISA SP76 substrate protocol Component based gas and fluid handling systems Offer flexibility in design and implementation of complicated flow systems for process sampling and analysis LEGOTM based approach to process sample handling Allows for optimal positioning of analyzers in a process stream NeSSI Modular Sampling Systems

3. What does NeSSI™ Provide • Simple “Lego®-like ” assembly (√) • Easy to re-configure • No special tools or skills required • overall lower cost of build – reduce time to configure/install by 75% • improved reliability • lower cost of ownership – reduce total cost by 40% • Standardized flow components (√) • “Mix-and-match” compatibility between vendors • Growing list of components • Standardized electrical and communication (+) • “Plug-and-play” integration of multiple devices • Simplified interface for programmatic I/O and control • Advanced analytics (+) • Micro-analyzers • Integrated analysis or “smart” systems

4. Where Does NeSSI™ Fit in the Lab • Instrument/Sensor Interfaces • Design standards make development simpler • Reduced toolset to be mastered • Reduced sample variability to account for • Calibration/validation built-in • Consistent physical environment for measurement • Stream switching and/or mixing allow generation of standards to match analytical requirements • Reaction monitoring • Microreactors and continuous flow reactors • Batch reactors (with fast loop) • Sample Preparation • Gas handling (mixing, generation, delivery) • Liquid handling (mixing, dilution, conditioning, etc.)

5. Benefits of Sampling Systems to Process Analysis • Conditioning and manipulation of sample introduced to analyzer • Better control of sample physical parameters • Phase • Temperature • Velocity Ability to implement sensors at points where measurement parameters are optimal Flexibility for performing calibration online without removing sensor Fast switching of streams for real-time measurement, calibration or validation

6. Raman/NIR/UV-Vis Sensor Module

7. Sensing Technologies • Gas Chromatography • Thermal Desorption (?) • Dielectric (√) • Spectroscopies • IR (?), NIR (+) • UV- Vis (+) • Raman (√) • Fluorescence (+) • Impedance (+) • Conductivity (√) • Refractive Index (√) • Vapochromic Sensors (+) • GLRS (+) • Particle Sizing • Light scattering (?) • Turbidity (+) • pH (√) • RGA (+) • Mass Spectrometry (√) • LC, SEC, IC (+) • Terrahertz (?)

8. Natural Gas Property Testing • Collaborative project with Brooks Instruments to test new Gas Property Instrument (GPI) for Gross Calorific Value and Wobbe Index of natural gas • Adaptation of thermal mass flow technology to measure physical parameters of gas • NeSSI™ system used to generate air/propane mixtures with known properties to simulate natural gas variations

9. GPI Testing Results Raw MFC (% Full Flow N2) Gross Heating Correlation Corrected (Vol %) Flow Wobbe Index Correlation

10. GPI Conclusions • First real application of gas blending or mixing on NeSSI in our lab • Developed preliminary LabVIEW software control for MFCs and pressure transducers • Brooks has agreed to assist in calibrating our MFCs for multiple gases • GPI results looked fairly good over planned application range of natural gas properties

11. Development of fast and selective gas sensors using vapochromic compounds

12. Vapochromic Probe Design & Sensing System GAS FLOW Vapochromic Film Probe Tip Dual Fiber Probe Excitation Fiber Light Source Blue LED Spectrograph & Detector Collection Fiber

13. Example NeSSI Sensor Interface • Sensor is a vapochromatic compound • Responds to different compounds by intensity and wavelength shifts in fluorescence signal • Optical detection using simple VIS spectrometer • LED excitation light source • Simple reflectance 2 fiber optical measurement • Use of BallProbe to provide single-sided optical interface • Vapochrome coated on ball surface • NeSSI™ system to control delivery and mixing of gas stream

14. Vapochromic Humidity Sensor - Measurment time – 100 ms - 3 reps per concentration • 2 PC calibration model • humidity range: 10 – 80% • Ohmic feedback control humidity generator used for reference stds.

15. Oxygen Gas Sensor Calibration • 2 PC PLS model • range = 0-100%

16. Response of Optical and DO Probes, Second Timed Exp. 120 0 Optical @560nm DO Probe 100 100 80 200 Sensor Optical Intensity (relative counts) DO reference measurement (O2 %) 60 300 40 400 20 0 50 100 150 200 Elapsed Minutes Optical response inverted and offset for comparison Vapochromic O2 Sensor vs Electrochemical DO probe

17. Vapochromic O2 Sensor Response

18. Vapochromic BTEX Sensing • Vapochromatic compound screening for benzene, toluene, ethylbenzene and m-xylene (BTEX) sensitivity and selectivity • Need to find the best available compounds for sensor array approach • Initial milestone: benzene detection • Establish sensitivity • (can we detect low enough levels?) • Characterize interferents • (can we distinguish mixtures?) • NeSSI™ system to control delivery and mixing of gas streams

19. NeSSI Gas/Vapor System Single inlet line (N2) Outlet lineto flow cell Standard Ace Glass impingers • NeSSI substrate with 3 MFC’s • 2 bubblers for vapor generation

20. Optical Flow Cell • Flow cell is a simple cross fitting • 6-around-1 fiber optic for source and collection • Delrin rod with sensing compound coated on end • Multiple crosses can be chained together for screening several compounds at once • Optical detection using simple VIS spectrometer, LED excitation light source • Simple reflectance optical measurement

21. Vapochromic NeSSI Sensor Design • simple design • reversible response • low power • inexpensive • NeSSI compat. • fast response times • high quantum efficiency • long term sensor stability • sensitive to a variety of analytes • large number of available vapochromic compounds (selectivity)

22. Experimental Details • Three gas streams mixed prior to outlet • MFC #1 pure N2 carrier (no bubbler) • MFC #2 run thru bubbler with benzene liquid • MFC #3 run thru empty bubbler (diluter) • MFC #1 and MFC #2 flow summed to 50% full flow (FF, 250 sccm) • As bubbler flow ↑ carrier flow ↓ • MFC #3 held at either 50% FF or 5% FF • Additional level of dilution between runs • Spectra collected every 2 seconds • LabVIEW program automates setting flow rates on MFCs, sequence timing, and data logging

23. Experimental Design/Program

24. Typical Automated Response

25. Full Spectrum Response

26. Vapochromic Response * MFC #3 run at 5% FF rather than 50% FF

27. Vapochromic Response • These are the 2 most sensitive compounds of the 6 looked at in this study • There is plenty of optical sensitivity to go to lower conc. • May need to implement “reset” techniques to zero response

28. Vapochromic #4 Response Differential response!!??

29. Screening Conclusions • Early results look good for benzene sensitivity • 2-3 candidates • Clearly need more dilution capability • Need to speed up the screening • Multiple simultaneous compounds • Switching/multiplexing NOT the answer • New multichannel spectrometers will improve screening

30. New Gas Sensor Testing System • More capability to generate analytical vapors, gas blending, and on-line dilution of vapor streams for method development work • Two systems (one at CPAC, the other at UM) will facilitate collaboration with Kent Mann • NSF Funding applied for (Aug. 06) • Bob Sherman, CIRCOR, committed to providing one system

31. 3 Voltmeters,1 Ammeter Thermocouple and Humidity sensor Thermocouple and Humidity sensors H2 in PEM Fuel Cell Air in Both Streams Purge to outside environment Tank (might run system without a tank) Fan/Blower Or Pump Fuel Cell Research • Goal: to study the water uptake properties of Nafion 112 by varying the relative humidity of the input gas streams to better understand membrane hydration and its effects on fuel cell performance. • Senior Project for ChemE undergrad student team • NeSSI™ System for gas flow and humidity sensing

32. Fuel Cell (cont.) • Simple NeSSI system design being built by Swagelok • Preliminary system calculations done by students • Vapochromic humidity sensors designed • Expect this activity begin this summer

33. Fluid Dynamics Modeling • Project with Dr. Finlayson and undergrad student Daniel Yates, Chem. E. • Utilize NeSSI™ components as objects for computation fluid dynamics modeling • Availability of NeSSI™ systems and parts allows for experimental work to verify/test model results • Provides academic training and exposure to real-world hardware in a compact and rugged platform • Can start simple and add complexity by including more components

34. Where are we now? • Development continues on control system • Data I/O, comm., and control hardware • Software for DAQ, automation and control • NeSSI microreactor system becoming reality • Parker Intraflow™ fluidic system delivered • IMM, Microglass, CPC mixers and reactor components here or coming soon • LC, Raman, dielectric, RI detection • Headspace and gas analysis systems • Horiba RGA analyzer running • Vapochromic sensors being designed and tested for NeSSI applications • GC interface to NeSSI under development with Infometrix (WTC Proposal submitted)