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rattus labbus (Multitrator employee)

Welcome!. Please click the left mouse button repeatedly to move through the slide show…. …. to this brief introduction to the M ULTITRATOR multi-mode titration system. rattus labbus (Multitrator employee). starting with a definition …. titrate

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rattus labbus (Multitrator employee)

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  1. Welcome! Please click the left mouse button repeatedly to move through the slide show… …. to this brief introduction to the MULTITRATOR multi-mode titration system rattus labbus (Multitrator employee)

  2. starting with a definition …. • titrate • /'tuytrayt/ verb (t) (titrated, titrating) to ascertain the quantity of a given constituent present in (a solution) by accurately measuring the volume of a liquid reagent of known strength until an end point is reached. [F titrer titrate + -ate1. See titre] --titration/tuy'trayshuhn/, n. • - The Macquarie Dictionary

  3. Thermometric Titrimetry …. Is a titration technique where endpoints are revealed by the rate of temperature change of the solution temperature. …. A thermistor is conveniently used to measure the change in temperature. …. Because only the rate of temperature change is important, it is unnecessary to calibrate the thermistor. …. Both exothermic and endothermic reactions between a titrant and an analyte may be used to define endpoints.

  4. another definition …. • thermistor • /ther'mistuh/ noun an electronic semiconductor, the resistance of which decreases rapidly with increase in temperature. [therm- + (trans)istor or therm- + (res)istor] • - The Macquarie Dictionary

  5. The business end of Multitrator Multitrator thermometric probe Temperature-sensing thermistor bead (~1.5mm diameter)

  6. Thermometric titrimetry can perform …. Acid/base (including weak acid/weak base) Redox Complexometric (eg, EDTA) Precipitation titrations (eg, Cl- with Ag+, SO42- with Ba2+, F- as NaK2AlF6) Non-aqueous (eg, free fatty acids in edible fats &oils) Moisture (endothermic reaction of water with triethyl orthoformate)

  7. Thermometric titration plots …. EXAMPLE: OH- and CO3-- Endpoint #2 (HCO3-) Endpoint #1 (OH-) Solution temperature Second derivativecurve for accurate location of endpoints Volume of titrant added

  8. Thermometric titration of phosphoric acid with sodium hydroxide

  9. The difference between potentiometric and thermometric titrimetry…. Potentiometric (eg, pH) titrations are free energy controlled: Go = -RTlnK Thermometric titrations are enthalpy controlled: Ho = Go + TSo In any reaction where the free energy does not oppose the entropy change, thermometric titrations will generally give sharper endpoints than potentiometric titrations

  10. The difference between potentiometric and thermometric titrimetry…. Thermometric titrimetry is a linear titration technique, wherein the signal is proportional to the amounts reacted Potentiometric titrimetry is a logarithmic technique, relying on the magnitude of equilibrium constants to obtain an inflection Where equilibrium constants are small (eg., titration of weak acids), thermometric titrimetry is generally superior

  11. Thermometric versus potentiometric (pH) titrations …. Simultaneous potentiometric (pH) and thermometric titration of acidic components in red wine… pH endpoints tagged blue… Thermometric endpoints tagged red…. pH titration curve

  12. Sensitivity of Thermometric Method Example: Determination of Chloride in Water

  13. Water, water, everywhere …. The thermometric titration way to determine moisture: HC(OCH2CH3)3 + 3H2O Triethyl orthoformate (TEOF) H+ HCOOCH2CH3 + 2CH3CH2OH • TEOF doesn’t react with water until acid-catalyzed in the sample solution • indefinite shelf life • benign reaction products

  14. H2O in lubricating oils….

  15. Catalytic Endpoint Thermometric Titrimetry (CETT) Example: Analysis of weakly acidic species in non-aqueous media using 0.1mol/L KOH in propan-2-ol Glass membrane pH probes rapidly dehydrate and lose response in non-aqueous solutions A thermometric probe is unaffected, but small heat of reaction is swamped by heats of solution and other thermal effects The solution: use an indicator system where the first excess of OH- catalyzes a strong exothermic reaction which serves to indicate the endpoint* CHCl3 + OH-→ CCl3- + H2O CCl3- + (CH3)2C=O + H2O→ (CCl3)(CH3)2C-OH + OH- *Smith, T. K. (2003) JAOCS 80 21-24

  16. Catalytic thermometric titration of FFA in edible oils

  17. Thermometric titrimetry is a well established technique 1886: Analysis of fuming sulphuric acid with dilute sulphuric acid (Howard) 1913: Titration of citric acid with ammonia (Bell & Cowell) 1920’s: Analysis of polyprotic acids, acid mixtures with Beckman thermometers. 1940’s: Introduction of thermopiles; highly accurate redox titrations. 1950’s: Introduction of thermistors 1960’s: Introduction of digital burettes; first automated thermometric titrators. Late-1980’s: First computer-controlled thermometric titrator 1999: Multitrator founded; first fully-automated multi-mode titration system featuring thermometric titrimetry.

  18. Multitrator - titration for now! • Computer controlled • Powerful software • Integrated with MS Excel • Compact control module • Easy to use • Good ergonomics • Fast sample turnaround Advanced, multi-sensor technology – not just thermometric!

  19. Multitrator most versatile! Titrations with potentiometric (pH, redox, ISE), photometric, chemiluminescence, conductometric, either alone or multiplexed with other sensors. Add sample changers, auto-samplers, auto-pipettes, pumps, valves and switches for full automation.

  20. Chemiluminescent titrations for trace acids.. A technique where the sensor never touches the solution… Open air demo of a chemiluminescent titration…

  21. Multitrator Chemiluminescent Titration Module…

  22. Sensitive, fast pH titrations with Multitrator…. Solid-state ISFET (Ion Selective Field Effect Transistor) pH probes are much, much faster than glass pH probes, but need the great Multitrator signal conditioning algorithm to get the most out of them…..

  23. Check out what’s under the hood ... Power supply 90-260 VAC 50-60 Hz Communication to computer Communication to burettes and sample changer Communication to RS422/485 devices Analogue inputs, digital outputs – relays, solenoids, pumps Serial comms port for microcontroller devices Multi-purpose sensor port Additional thermometric sensor ports Potentiometric sensor port Thermometric sensor port

  24. The simplest solution for full titration automation…… • The same thermometric sensor used for most determinations • Perform different types of titration in the same carousel load • “Daisy-chain” up to 8 burettes • Import method and sample data from a LIMS • Control entire sequence with a single mouse click

  25. ending with a definition …. • multitrate • /muhlti’trayt/ verb (t) (multitrated, multitrating) to conduct a titration using • the most versatile and advanced multi-mode titration system, esp. using thermometric titrimetry [L multus much, many + F titrer titrate + -ate1. • - Lab Rat Dictionary

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