CONNECTIONS. The Thermal Conductivity Detector
|
|
- Melissa Nicholson
- 5 years ago
- Views:
Transcription
1 38 LCGC NORTH AMERICA VOLUME 4 NUMBER 1 JANUARY GC CONNECTIONS The Thermal Conductivity Detector Thermal conductivity detectors have been in use since before the beginning of gas chromatography. Essential for fixed-gas detection no substitute has the same ease of use and stability thermal conductivity detectors also are employed when the auxiliary or combustion gases required by flame ionization or other detectors are unsafe or impractical. Although they cannot match the sensitivity of ionization detectors, thermal conductivity detectors are the third most used detector, surpassed only by flame ionization and bench-top massspectrometry detectors. This month s installment of GC Connections takes a look at the operating principles and inner workings of the thermal conductivity detectors. John V. Hinshaw GC Connections Editor Gas chromatography (GC) detectors can be classified into two broad categories: bulkproperty and chemical-specific. Flame ionization detectors (1) fall into the chemical-specific class: molecules that contain carbon-hydrogen bonds are ionized and the resulting current is amplified to produce a signal, while other chemical classes produce little or no response. Thermal conductivity detectors, on the other hand, do not interact with solutes chemically but instead respond to changes in a bulk physical property, namely, the thermal conductivity of pure carrier gas compared with the conductivity of the solute carrier-gas mixture passing through the detector reference and sample cells, respectively. Thermal conductivity detection (TCD) responds in proportion to the concentration in the sample cells of any gas that has a thermal conductivity different than that of pure carrier gas. The sensitivity of TCD response to various solutes is dictated by the solutes thermal conductivities relative to the carrier: solutes with thermal conductivities close to that of the carrier gas will elicit small responses and those that differ more from the carrier gas in their thermal conductivities will generate larger sensitivities. This makes TCD respond universally without dependence upon specific chemical elements or structures, beyond any indirect effects on solutes thermal conductivity. Thermal conductivity detectors comprise one or more active thermal-sensing elements in two gas streams: the reference stream contains pure carrier gas and the sample stream contains the column effluent. The thermal elements temperatures are nearly the same with pure carrier gas flowing in both the sample and the reference streams. The thermal conductivity of the gas in the sample cell changes as peaks are eluted from the column, while that of the reference stream remains constant. The temperature of the affected sample-sensing element changes in response, while the reference side stays the same and the resulting imbalance changes the circuit output level. Figure 1 shows a typical chromatogram of gases using a thermistor bead thermal conductivity detector. Thermal Conductivity The coefficient of thermal conductivity determines the rate of heat transfer, or flux, through a pure gas or gas mixture that spans a temperature gradient. Thermal conductivity is defined in terms of the heat flux q z and thermal gradient dt/dz by the following equation: q z dt = λ d z [1] The units for are cal cm -1 s -1 C -1. The negative sign in equation 1 reflects that fact that heat flows from higher to lower temperatures. Values of for some pure gases encountered in GC are listed in Table I. Methane has one of the highest thermal conductivities for hydrocarbons and benzene one of the lowest hydrocarbon conductivities. Equation 1 indicates that higher thermal conductivities and larger temperature gradients will produce a greater heat flux in a onedimensional system with correspondingly larger responses to changes in gas thermal conductivity. In a real detector, the dynamics of heat flow depend strongly upon the three-dimensional structure
2 40 LCGC NORTH AMERICA VOLUME 4 NUMBER 1 JANUARY (a) 8 (b) TCD response (mv) Time (min) Figure 1: TCD chromatogram of C 1 and C hydrocarbons plus air and fixed gases. Shown are (a) positive and (b) negative polarity traces. Columns: (a).0 m 1.0 mm micropacked 100/10 mesh porous polymer at 9.0 sccm, (b).0 m 1.0 mm micropacked 80/100 mesh molecular sieves A at 9.0 sccm; carrier gas: helium; column temperature: 73 C; detection: thermistor bead TCD at 73 C; sample: 0. ml of the gas mixture at 1.7 psia. Peaks: 1 carbon dioxide (773 ppmv), ethane (170 ppmv), 3 acetylene (8 ppmv), 4 ethylene (176 ppmv), hydrogen (1,600 ppmv), 6 oxygen (887 ppmv), 7 nitrogen (balance), 8 methane (740 ppmv), 9 carbon monoxide (81 ppmv). (Courtesy of Serveron Corporation, Hillsboro, Oregon.) and flow pattern through the detector cells as well as the gases thermal conductivities and the temperature gradient. Thus, TCD response varies significantly with different designs. Most solutes have conductivities that are lower than common carrier gases such as helium, argon, or nitrogen. So, in general, the thermal conductivity of a carrier solute mixture will be lower than pure carrier gas. This means that the temperature of the sensing elements in the column effluent stream will increase as peaks are eluted. There is a risk of overheating and damaging the thermal sensing elements if they are operated Table I: Thermal conductivity of common gases at 0 C Gas Thermal Conductivity, (cal.cm -1 s -1 C ) * Helium 34.8 Hydrogen 41.6 Nitrogen.8 Argon 4.0 Oxygen.9 Carbon monoxide.6 Methane 7. Benzene. * Values from reference. Circle 30
3 JANUARY 006 LCGC NORTH AMERICA VOLUME 4 NUMBER Figure : Schematic diagram of thermal conductivity detector block and electronics. 1 TCD block, sample gas inlet from column, 3 sample gas outlet, 4 reference gas inlet, reference gas outlet, 6 power supply for filaments, 7 bridge balance adjustment, 8 amplifier, 9 amplifier offset adjustment, 10 output to A/D converter and signal processing. close to their upper temperature limits to obtain the highest sensitivity. Some thermal conductivity detectors can operate the elements at a constant temperature, measuring the heat required to keep the temperature constant rather than measuring the increase in temperature as peaks are eluted. Measuring Thermal Conductivity The thermal conductivities of the carrier gas and the solute carrier mixture are measured ratiometrically in TCD. The thermal-sensing elements in a thermal conductivity detector are made either from positive temperature coefficient materials such as metal filaments that exhibit an increasing electrical resistance with increasing temperature, or from negative temperature coefficient materials such as thermistors in which the electrical resistance decreases as the temperature increases. Filament thermal conductivity detectors span a wider operating temperature range than do thermistor detectors, but the latter devices can yield somewhat better sensitivities at operating temperatures below about 100 C. Sensing materials are chosen carefully for their electrical properties. A metal with a high-temperature coefficient is desirable for TCD filaments. Tungsten or tungsten rhenium alloys commonly are employed. For thermistor detectors, a bead with a nominal resistance of around 1 3 k at the operating temperature often is used. In either case, the thermal sensing elements must be closely matched to each other to bring the system and its electronics close to balance in the presence of pure carrier gas. Both types of thermal sensor operate with similar detector layouts and circuitry, although the voltages and currents employed differ significantly. Figure shows a schematic layout of a four-wire filament thermal conductivity detector. Four cells (represented by the shaded areas in Figure ) are drilled into a metal block, and a thin resistance-wire filament of about in. outer diameter is suspended inside each cell. Pure carrier gas is routed to two of the cells (the reference cells), and column effluent to the other two (the sample cells). The block is heated to a constant temperature of about 0 C above the maximum operating column temperature and a small current on the order of 0 to several hundred milliamperes supplies additional heat to each filament. After an equilibration period, the filaments reach a constant temperature above the block temperature that is determined by the flow rate and conductivity of pure carrier gas through each cell and by the filament Circle 31, 3
4 4 LCGC NORTH AMERICA VOLUME 4 NUMBER 1 JANUARY 006 current. Thermal leakage by radiation, convection, and conduction through the filament connections is significant, but is assumed to be constant. When a peak is eluted from the column, the different conductivity of the carrier solute mixture causes a change in the filament temperatures in the sample cells while the reference cell filament temperature remains constant. The change in filament resistance caused by solute passage through the sample cells is measured with a Wheatstone bridge circuit, also shown in Figure. As the resistance of the filaments changes, a corresponding positive or negative signal is produced at the amplifier output. Electrical balancing and zeroing circuits also are included in TCD amplifiers as noted in Figure. In modern GC systems, TCD output is filtered, digitized, and processed in much the same manner as for a flame ionization detector (see reference 1 for more details on detector signal processing). (a) In general, filament-type thermal conductivity detectors can be operated in either a constant-current mode or a constant-temperature mode. In constant-current operation, the filament temperatures are allowed to vary as solutes are eluted (b) Figure 3: Cross sections of (a) conventional packed-column and (b) low-volume TCD cells. 1 gas inlet, gas outlet, 3 end seals and wire mounts, 4 filament wire, electrical connections. 3 and the cell electrical current is kept constant. In the constant-temperature mode, the cell current is reduced or increased as required to keep the filament temperatures constant. An alternative arrangement, not shown here, uses a single-fila- Circle 33
5 JANUARY 006 LCGC NORTH AMERICA VOLUME 4 NUMBER 1 43 ment cell into which reference gas and column effluent are alternately routed by a microvalve operating at about 10 Hz. The resulting chopped signal is synchronously demodulated to produce the detector output. Detector Geometry As peaks are eluted from the column and pass through the detector sample cells, their widths and thus, their resolution, can be adversely affected by too-large cell volumes and unswept areas in the detector. Thermal conductivity detectors that are intended for general packed-column use generally are rugged and stable, but they might not be well suited for use with wide-bore capillary columns with inner diameters 0.3 mm. Although makeup gas can be used to better sweep capillary column flows through the detector cells, the extra flow will dilute the column effluent and reduce sensitivity. In addition, such detectors might not respond rapidly enough to capillary peaks. Low-volume thermal conductivity detectors can handle most packed-column flow rates as well as wide-bore capillary columns down to around 3 ml/min, and generally are considered best for multipurpose applications. Figure 3 illustrates a typical cell design often found in general purpose packed-column detectors (Figure 3a) and a low-volume cell (Figure 3b). The differentiating factor here is the manner in which the electrical leads to the sensing elements are routed. The first type is easier to replace but tends to have a larger internal volume to accommodate the two legs of the sensing element mount. The second type requires factory service to replace a burned-out element but occupies lower volumes than the first. Choice of Carrier Gas The thermal conductivity of the carrier solute mixture changes in direct proportion to solute concentration from about 1 part-per-million by volume (ppmv, ) at the lower end up to several percent: typical thermal conductivity detectors have a linear dynamic range of close to There is one notable exception: low percent levels of hydrogen separated with helium carrier gas. Even though pure hydrogen has a higher conductivity than pure helium and would be expected to increase the conductivity of an eluting solute carrier gas mixture, the thermal conductivity of a mixture of these two gases decreases relative to pure helium at low hydrogen concentrations up to about 8% and then decreases at higher hydrogen concentrations. The result can be disconcerting and impossible to quantify W -shaped peaks for hydrogen compositions in the percent range (3). A special carrier-gas blend of 10% hydrogen in helium is available for this situation. Hydrogen peaks will then go in the opposite (negative) direction to other peaks with lower thermal conductivities, as also is the case when analyzing hydrogen with nitrogen or argon carrier. In the case of hydrogen, either of these latter two carrier gases will produce a larger response than with helium carrier. As can be seen from the previous example, the best choice of carrier gas for TCD applications can be a compromise. Helium carrier gas, with its high thermal conductivity, yields larger TCD responses than nitrogen or argon carrier for nonhydrogen peaks, and normally is chosen if helium itself is not one of the solutes to be separated. Its high conductivity also allows TCD filaments to be operated at higher currents without risking filament overheating and burnout. Hydrogen sensitivity is low, however, as seen in Figure 1, where the hydrogen peak is small yet represents a high gas concentration level. If high hydrogen sensitivity is desired while also separating air components and light hydrocarbons, then a flame ionization detector can be placed in series with the thermal conductivity detector exit TCD does not destroy or alter the eluted components and used with argon carrier gas. The hydrogen sensitivity is higher than it would be with helium or a hydrogen helium carrier-gas mixture, other air components such as carbon dioxide and oxygen have good responses, and the hydrocarbons are left to the much higher sensitivity flame ionization detector. Note that nitrogen is not suitable as a carrier gas when oxygen or carbon monoxide is to be detected: the thermal conductivities of these three gases are very close. If the carrier gas has an intermediate thermal conductivity then solutes with lower conductivities will cause the detec- Circle 34
6 44 LCGC NORTH AMERICA VOLUME 4 NUMBER 1 JANUARY tor to respond in a direction opposite to those solutes with higher conductivities. For example, when separated with argon or nitrogen carrier gas, a mixture of C 1 C 3 hydrocarbons in helium will produce positive peaks for the hydrocarbons and a negative peak for the helium. If helium were selected as the carrier, the thermal conductivity detector would not respond to helium in the injected mixture (that is, as long as the eluted helium peak is pure). TCD will respond to impurities such as oxygen, water, or nitrogen that are coeluted with the helium peak. Note also that if the carrier gas itself contains a few parts per million of nitrogen or other contaminant then a limited response to even a pure helium peak will be seen. Thus, contrary to some chromatographic intuition, carriergas purity can be important even for a TCD system. In addition to the series-detection arrangement described previously, TCD also can be applied in microscale preparative GC by using a fraction collector at the detector outlet to obtain enough pure solute for nuclear magnetic resonance (NMR), elemental analysis, or other ancillary analytical technique. TCD also is useful in fragrance research. The eluted peaks are detected by a thermal conductivity detector, often along with an ionization detector operated in parallel, and the GC effluent is humidified before olfactory evaluation. Setup and Operation Setup and operation of thermal conductivity detectors are simpler than for combustion detectors such as the flame ionization detector because there are no combustion gas flows to set and no flame to ignite. The procedure involves installing the columns, setting the carrier-gas and reference flows, and then turning on the detector at a selected sensitivity or filament current setting. Flow rates: At the initial column temperature, the total flows through the sample and reference sides of the thermal conductivity detector should be within about 10% of each other. Measure the flow at the sample and reference exit ports. Set the column flow first, and then set the reference to match. If makeup gas is used with a capillary column, be sure to set the reference flow to equal the column plus makeup flow rates. It is important to maintain a constant gas flow through a thermal conductivity detector during operation. If the GC oven is to be temperature programmed, constant carrier-gas flow operation is essential. Use the constant-flow mode in an electronic pressure controlled system, or use constant mass-flow carrier and reference gas regulators. Avoid using a constant pressure setting for the carrier gas. Detector current: In general, to obtain the best sensitivity, the highest possible filament current should be used. In a microprocessor-controlled gas chromatograph, the filament current is set in discrete steps. In analog systems, there will be a knob or a series of switch settings for this purpose. Referring to the instrument manual, select the highest current setting that does not exceed the maximum level for the carrier gas and cell temperature that you are using. Currents for thermistor detectors are on the order of 8 1 ma, much lower than typical levels of ma for filament detectors. Electrical balance: Many thermal conductivity detectors have both a balance setting that affects the sensor current balance through the bridge circuit plus another zeroing circuit that offsets the detector output as it appears at the amplifier. It is important to adjust the sensor balance control to bring the detector cells near electrical balance before applying additional external zeroing offsets. If the amplifier output is zeroed to offset detector cells that are already far out of balance, the linearity and dynamic range can be cut short. To balance the detector, turn on the instrument, set the detector temperature, flows, and cell current and then allow the detector baseline to stabilize. Turn off detector autozeroing and observe the detector signal on a chart recorder or on the instrument display if a direct readout is provided. Adjust the balance control until the signal is near zero. Then, turn on autozeroing so that the signal is zeroed and adjusted as required for subsequent digitization and data handling. This procedure will ensure that the cell is in balance at the baseline. When the detector is heated and stabilized, it is ready for use. Troubleshooting Thermal conductivity detectors are not subject to as many problems as other GC detectors because they are somewhat simpler in construction and are not as sensitive. However, there are several common problems that are easily remedied. Filament protection circuits: Many TCD designs include one or more means of protecting the filaments from potentially damaging conditions. The most common scheme is to monitor the filament temperatures as indicated by their resistance. If the maximum temperature is exceeded, current is removed, and the detector shuts down. This condition is indicated by a complete lack of response to peaks. The signal will usually go fully positive or negative if a filament does burn out, and it will not be possible to balance the detector. If the filament protection circuit trips repeatedly, then either the current setting is too high for the carrier gas and detector temperature in use, or the detector has been set too far out of balance. The second type of protection circuit temporarily interrupts the filament current during the passage of a large peak and restores current after the peak has passed. This out-of-range condition is intended mainly as a protection against filament burnout from the higher filament temperatures during a large solvent peak. During the out-of-range period, the detector is not delivering a quantitative signal: it is clipped. However, even without the protection, the signal would be clipped for such large peaks. If a quantitative peak area is needed, a lower filament current should be selected. Thermistors tend to be more rugged than filaments and do not burn out commonly. Flow effects: The detector also responds to changes in column or reference flow rates. If one of the flows is changed, it might be necessary to rebalance the detector or make a corresponding change to the other flow. During a temperature-programmed run, the flow through the column changes because of changes in the carrier-gas viscosity. Even using a mass-flow controller, significant transient fluctuations can occur in the
7 column flow. These temperature-related effects, which are seen in addition to drift from column bleed, cause the baseline to drift up or down during a run. A matching reference column or restrictor often is installed in the oven so that both sides of the detector experience the same flow changes with changing oven temperature. Even in this case, the two flows might not perfectly cancel each other out; electronic baseline profile compensation is very useful for ironing out these residual effects. Inverted peaks: Peaks that represent solutes with thermal conductivities greater than the carrier gas, such as helium in nitrogen carrier or hydrogen in argon carrier are expected to have the opposite polarity of solutes with lower thermal conductivities than the carrier gas, such as hydrocarbons in helium, nitrogen, or argon carrier. If all peaks are inverted, then the detector polarity is backwards. When two columns are in use, one connected to either side of the thermal conductivity detector, the TCD polarity should be reversed when injecting on the second column. Gradual sensitivity losses: Sometimes a gradual loss of sensitivity is observed over a period of weeks or months. This loss usually is caused by slow degradation of the filaments or thermistor beads due to corrosion or to contaminant deposition. The only practical solution is to replace the damaged elements. Note that replacement elements are sold as matched pairs. Do not try to replace only one of them you probably would not be able to balance the detector properly. If you have a low-volume detector with feedthrough filaments, the whole block will need to be sent to the manufacturer to be rebuilt. Many instrument companies will give a credit for returning a damaged unit in exchange for a completely refurbished or new detector. should last for the life of the gas chromatograph. References (1) J.V. Hinshaw, LCGC 3(1), (00). () S. Dal Nogare and R.S. Juvet, Gas-Liquid Chromatography Theory and Practice (Interscience Publishers, New York, 196), p. 19. (3) B.J. Gudzinowicz, in The Practice of Chromatography, L.S. Ettre and A. Zlatiks, Eds. (Interscience Publishers, New York, 1967), p. 46. JANUARY 006 LCGC NORTH AMERICA VOLUME 4 NUMBER 1 4 John V. Hinshaw GC Connections editor John V. Hinshaw is senior staff engineer at Serveron Corp., Hillsboro, Oregon, and a member of LCGC s editorial advisory board. Direct correspondence about this column to GC Connections, LCGC, Woodbridge Corporate Plaza, 48 Route 1 South, Building F, First Floor, Iselin, NJ 08830, lcgcedit@lcgcmag.com. For an ongoing discussion of GC issues with John Hinshaw and other chromatographers, visit the Chromatography Forum discussion group at Conclusion The thermal conductivity detector is a reliable device with good sensitivity and universal response. Its design simplicity makes it easy to set up, maintain, and troubleshoot. Some care is required in selecting carrier gases, setting column and reference flows, and choosing the correct sensing current. With proper care, a thermal conductivity detector Circle 3
Gases&Technology. Measurement of Impurities in Helium Using the Dielectric Barrier Discharge Helium Ionization Detector. FEATURE.
Gases&Technology FEATURE Measurement of Impurities in Helium Using the Dielectric Barrier Discharge Helium Ionization Detector. B Y M A T T H E W M O N A G L E Abstract Bulk gases are often delivered to
More informationTROUBLESHOOTING. Dwell Volume Revisited. Gradient transfer does not have to be problematic.
458 LCGC NORTH AMERICA VOLUME 24 NUMBER 5 MAY 2006 www.chromatographyonline.com LC TROUBLESHOOTING Dwell Volume Revisited Gradient transfer does not have to be problematic. John W. Dolan LC Troubleshooting
More informationMultiple Gas#5 GC configuration Jan 2016
History: Unfortunately there is no single column that can separate: Hydrogen Oxygen Nitrogen Methane CO CO2 Ethane Water Propane Butane Pentane Over the years SRI Instruments has devised several solutions
More informationMETHOD 3C - DETERMINATION OF CARBON DIOXIDE, METHANE, NITROGEN, AND OXYGEN FROM STATIONARY SOURCES
METHOD 3C - DETERMINATION OF CARBON DIOXIDE, METHANE, NITROGEN, AND OXYGEN FROM STATIONARY SOURCES 1. Applicability and Principle 1.1 Applicability. This method applies to the analysis of carbon dioxide
More informationDetector Carrier Gas Comments Detector anode purge or reference gas. Electron Capture Nitrogen Maximum sensitivity Nitrogen Argon/Methane
Gas requirements Gases for packed columns The carrier gas you use depends upon the type of detector and the performance requirements. Table 520-1 lists gas recommendations for packed column use. In general,
More informationLINEAR TRANSFORMATION APPLIED TO THE CALIBRATION OF ANALYTES IN VARIOUS MATRICES USING A TOTAL HYDROCARBON (THC) ANALYZER
LINEAR TRANSFORMATION APPLIED TO THE CALIBRATION OF ANALYTES IN VARIOUS MATRICES USING A TOTAL HYDROCARBON (THC) ANALYZER Michael T Tang, Ph.D. Grace Feng Greg Merideth Rui Huang Matheson Gas Applied Lab
More informationAPPLICATION NOTE. Fast Analysis of Coal Mine Gas Using the INFICON 3000 Micro GC ABSTRACT
APPLICATION NOTE Fast Analysis of Coal Mine Gas Using the INFICON 3000 Micro GC ABSTRACT The INFICON 3000 Micro GC provides two fast and accurate solutions for the analysis of coal mine gas components.
More informationGas Chromatography. MS Vent Enhancement to the PreVent System to Optimize Operation with the TurboMass, TurboMass Gold, and Clarus 500 GC/MS Systems
Inorganic Analysis Chromatography Molecular Spectroscopy Thermal/Elemental Analysis Informatics Gas Chromatography MS Vent Enhancement to the PreVent System to Optimize Operation with the TurboMass, TurboMass
More informationYour local gas generation partner. Precision series Modular gas generation solution for GC.
Your local gas generation partner Precision series Modular gas generation solution for GC www.peakscientific.com Perform with Precision Specifically designed and engineered for GC laboratory applications,
More informationMETHOD 25A - DETERMINATION OF TOTAL GASEOUS ORGANIC CONCENTRATION USING A FLAME IONIZATION ANALYZER
1250 METHOD 25A - DETERMINATION OF TOTAL GASEOUS ORGANIC CONCENTRATION USING A FLAME IONIZATION ANALYZER 1.0 Scope and Application. 1.1 Analytes. Analyte CAS No. Sensitivity Total Organic Compounds N/A
More informationA Journal of Practical and Useful Vacuum Technology. By Phil Danielson
A Journal of Practical and Useful Vacuum Technology From By Phil Danielson Thermal Conductivity Gauges Thermal conductivity pressure gauges are extremely common in vacuum technology, but an understanding
More informationThree Columns Gas Chromatograph Analysis Using Correlation between Component's Molecular Weight and Its Response Factor
Three Columns Gas Chromatograph Analysis Using Correlation between Component's Molecular Weight and Its Response Factor Anwar Sutan, Metco Services Ltd. Charles Johnson, Metco Services Ltd. Jason Laidlaw,
More informationProtective Atmospheres, Measurement Technologies and Troubleshooting Tools
Protective Atmospheres, Measurement Technologies and Troubleshooting Tools Furnace atmospheres are critical to meet metallurgical specifications defined by control processes. The makeup of a furnace s
More informationMASS FLOW SYSTEMS MASS FLOW MEASURING, CONTROLLING AND BLENDING SYSTEMS
MASS FLOW SYSTEMS MASS FLOW MEASURING, CONTROLLING AND BLENDING SYSTEMS Using state-of-the-art measuring and microprocessor technologies, Advanced has assembled a series of systems which can measure mass
More informationYour local gas generation partner. Precision series Modular gas generation solution for GC.
Your local gas generation partner Precision series Modular gas generation solution for GC www.peakscientific.com Perform with Precision Specifically designed and engineered for GC laboratory applications,
More informationYour local gas generation partner. Precision series Modular gas generation solution for GC.
Your local gas generation partner Precision series Modular gas generation solution for GC www.peakscientific.com Perform with Precision Specifically designed and engineered for GC laboratory applications,
More informationSeries 6517 Katharometers. The ideal equipment for Process Monitoring and Control. Robust no moving parts. Designed for continuous industrial use
Data sheet Katharometers The ideal equipment for Process Monitoring and Control Designed for continuous industrial use Long working life Suitable for flammable gases CENELEC certified (ATEX) to EExia IIC
More informationTitle: Standard Operating Procedure for Measurement of Ethylene (C 2 H 4 ) in Ambient Air by Reduced Gas Detection (RGD)
Procedure No: SOP-026 Revision No: 1.0 January 24, 2011 Page No.: 1 of 10 1. INTRODUCTION AND SCOPE To obtain timely data for the purpose of air quality assessment, air quality trend reporting and to meet
More informationApplications Note: Use of "pentane equivalent" calibration gas mixtures
Introduction The gas that is used to verify accuracy is every bit as important as the detector itself when it comes to worker safety. Choosing (and using) the right mixture is critical to the success of
More informationno peaks missing peaks too small peaks increasing retention decreasing retention
GC Troubleshooting We can help you. 1. Observation: no peaks no peaks missing peaks too small peaks increasing retention decreasing retention declining baseline rising baseline bleeding plateaus interfering
More informationAFC. SDPROC and AFC Analog Mass Flow Controller ANALOG MASS FLOW CONTROLLERS. Principles of Operation. Design Features
ANALOG MASS FLOW CONTROLLERS Model AF mass fl ow controllers are designed to indicate fl ow rates and control set fl ow rates of gases. Each of these units incorporates an advanced straight tube sensor
More informationThe Experts in Vacuum Solutions
By Woodrow Farrow - Reprinted with permission from Specialty Gas Report Vacuum: a space that is relatively empty of matter, especially when that void has been created through artificial means. The earth
More informationASTM 3612/TOGA/Dissolved Gas GC Revised October 2013
The SRI ASTM 3612/TOGA/ Dissolved Gas GC configuration ( TOGA GC ) permits measurement of gasses dissolved in water, oil or other liquids, and is based on the requirements of ASTM method 3612, option C,
More informationExperiment GC : Analysis of BTEX by GC-FID
46 Experiment GC : Analysis of BTEX by GC-FID Learning Goals: Familiarity with gas chromatography Gain experience in temperature programming and method development Correctly use an internal standard, and
More informationSuperior Result from Analytical Instruments The constant purity of the nitrogen improves system stability and ensures reproducible results
Nitrogen Generator Whisper-N2 Series Features Membrane Technology Superior Result from Analytical Instruments The constant purity of the nitrogen improves system stability and ensures reproducible results
More informationMODEL GENERA PURGE TURBINE INSTR DANGER HIGHLY TOXIC AND OR FLAMMABLE LIQUIDS OR GASES MAY BE PRESENT IN THIS MONITORING SYSTEM.
275R MODEL 275R POR ORTABLE TURBINE GENERA ENERATOR PURGE GAS ANAL NALYZER INSTR NSTRUCTION MANU ANUAL AL DANGER HIGHLY TOXIC AND OR FLAMMABLE LIQUIDS OR GASES MAY BE PRESENT IN THIS MONITORING SYSTEM.
More informationSystem Overview. TCD Detector temperature setpoint Regulator
System Overview POPULAR CONFIGURATION GCs Your educational TCD GC is configured on the compact 310 chassis. It is equipped with a TCD Detector, a temperature programmable Column Oven, a 3 Silica Gel packed
More informationGenerating Calibration Gas Standards
Technical Note 1001 Metronics Inc. Generating Calibration Gas Standards with Dynacal Permeation Devices Permeation devices provide an excellent method of producing known gas concentrations in the PPM and
More informationAPPLICATION NOTE. GC Integrated Permeation Device
GC Integrated Permeation Device GC-integrated Design PPB to PPM Level Calibration No Cylinders or Regulators Required Option for Dual Ovens Cost Effective, Safe, Clean, Flexible, NIST Traceable Keywords:
More informationThis GC has two columns (I think new columns can be ordered from Restek)
SRI 8610C GC Ann s Notes 11-17-2014 Introduction This is the GC as it came from the manufacturer This GC has two columns (I think new columns can be ordered from Restek) 1. Hayesep D: Column 1 a. Separating
More informationH 2. Sensor Series Take no risk! Install a Hydrogen Sensor in your Gaschromatograph
Sensor Series 9000 Take no risk! Install a Hydrogen Sensor in your Gaschromatograph Carrier Gases for GC Probably more than 90% of the present GC instruments run with helium as carrier gas. Some people
More informationBest Practice Guide, Servomex 2700
For full installations details refer to the. Best Practice Guide, Servomex 2700 Mounting: General Guidelines: Servomex 2700 Control Units and air supplies (utilities units) should, ideally, be mounted
More informationARTICLE IN PRESS. Nuclear Instruments and Methods in Physics Research A
Nuclear Instruments and Methods in Physics Research A 602 (2009) 845 849 Contents lists available at ScienceDirect Nuclear Instruments and Methods in Physics Research A journal homepage: www.elsevier.com/locate/nima
More informationRapid and Reliable Detection of Dissolved Gases in Water
Rapid and Reliable Detection of Dissolved Gases in Water Andrea Caruso and Massimo Santoro Thermo Fisher Scientific, Milan, Italy Application Note 005 Key Words Chromeleon CDS, Environmental, Fracking,
More informationDesign Features. General Description
Model thermal Mass Flow Controllers are designed to indicate and control set flow rates of gases. The combines the characteristics and accuracy of conventional mass flow devices into a unique compact design
More informationUsing the PreVent System in Time-Saver Mode with the AutoSystem XL Gas Chromatograph and the TurboMass Mass Spectrometer
application Note Gas Chromatography/ Mass Spectrometry Using the PreVent System in Time-Saver Mode with the AutoSystem XL Gas Chromatograph and the TurboMass Mass Spectrometer Overview A mass spectrometer
More informationRetention Time Locking: Concepts and Applications. Application
Retention Time Locking: Concepts and Applications Application Gas Chromatography December 1997 Authors Vince Giarrocco Bruce Quimby Matthew Klee Agilent Technologies, Inc. 2850 Centerville Road Wilmington,
More informationLFE OEM TCD - Thermal Conductivity Detector
LFE OEM TCD - Thermal Conductivity Detector Key features Quick response - T90 3 sec Extremely suppressed ranges High corrosion resistance High temperature capability up to 180 C Infallible containment
More information3 Flow and Pressure Control
3 Hydrogen shutdown Column shutdown Turning gas flows on and off EPC-controlled streams NonEPC-controlled streams Electronic Pneumatic Control (EPC) Interpreting flow and pressure readings Configuration
More informationWhite Paper. Chemical Sensor vs NDIR - Overview: NDIR Technology:
Title: Comparison of Chemical Sensor and NDIR Technologies TSN Number: 25 File:\\MII- SRV1\Metron\Bridge_Analyzers\Customer_Service_Documentation\White_Papers\25_G en EGA NDIR vs Chemical Sensor.docx Created
More information6890 GC Not Ready Messages (A16010)
6890 GC Not Ready Messages (A16010) This document is believed to be accurate and up-to-date. However, Agilent Technologies, Inc. cannot assume responsibility for the use of this material. The information
More informationThis test shall be carried out on all vehicles equipped with open type traction batteries.
5.4. Determination of hydrogen emissions page 1 RESS-6-15 5.4.1. This test shall be carried out on all vehicles equipped with open type traction batteries. 5.4.2. The test shall be conducted following
More information29th Monitoring Research Review: Ground-Based Nuclear Explosion Monitoring Technologies
IMPROVED CALIBRATION AND OPERATION OF A STABLE-GAS QUANTIFICATION MANIFOLD AS PART OF A RADIOXENON COLLECTION SYSTEM ABSTRACT Richard M. Williams, James C. Hayes, and Randy R. Kirkham Pacific Northwest
More informationINSTRUMENT INSTRUMENT YL INSTRUMENT
INSTRUMENT INSTRUMENT INSTRUMENT Nitrogen Generator Whisper-N2 Series Features Membrane Technology Compressed air is forced through a hollow fiber membrane, with selective permeation of the different components
More informationColumbus Instruments
0215-003M Portable O 2 /CO 2 /CH 4 Meter User s Manual Columbus Instruments 950 NORTH HAGUE AVENUE TEL:(614) 276-0861 COLUMBUS, OHIO 43204, USA FAX:(614) 276-0529 1 www.colinst.com TOLL FREE 1-800-669-5011
More informationANNEX AMENDMENTS TO THE INTERNATIONAL CODE FOR FIRE SAFETY SYSTEMS (FSS CODE) CHAPTER 15 INERT GAS SYSTEMS
Annex 3, page 2 ANNEX AMENDMENTS TO THE INTERNATIONAL CODE FOR FIRE SAFETY SYSTEMS (FSS CODE) CHAPTER 15 INERT GAS SYSTEMS The text of existing chapter 15 is replaced by the following: "1 Application This
More informationUser manual. TC-20 Sample conditioning and dry-purge rig. QUI-0003 Version 6.3 September
Version 6.3 September 2013 User manual TC-20 Sample conditioning and dry-purge rig Page 2 Contents 1. Introduction to the TC-20... 3 1.1 Tube conditioning... 3 1.2 Dry-purging... 3 2. Required services...
More informationCarrier Gases in Capillary GC
Carrier Gases in Capillary GC LC Columns and Consumables Mark Sinnott Application Engineer January 15, 2009 CARRIER GAS Mobile Phase Carries the solutes down the column Selection and velocity influences
More informationGCMSD-Headspace Analysis SOP
Before you start GCMSD-Headspace Analysis SOP Method and Sequences names are restricted to 50 characters (MSD program will crash otherwise) The GC oven and Injection Ports need to be cooled to 50 oc to
More informationSensoric 4-20 ma Transmitter Board Operation Manual
Sensoric 4-20 ma Transmitter Board Operation Manual 1 Content Features Operation Manual Technical Data Mechanical Dimensions Remarks & Contact information 2 Features Soldered sensor cell (non replaceable)
More informationX-Flow Mass Flow Controller 授权代理 : 北京品超思瑞科技学院公司
X-Flow Mass Flow Controller 2 Highlights Parker Hannifin Precision Fluidics Division is excited to introduce X-Flow, a new easy to use general purpose mass flow controller for your instrument, lab, or
More informationTechnical Data Sheet MF010-O-LC
Technical Data Sheet MF010-O-LC - 1 - 1. Properties The oxygen measuring system MF010-O-LC determines the oxygen content in gas mixtures up to a temperature of 250 C. It is particularly suitable for the
More informationXMO2. Panametrics Smart Oxygen Analyzer. Applications. Features. bhge.com. An oxygen transmitter for use in:
XMO2 Panametrics Smart Oxygen Analyzer Applications An oxygen transmitter for use in: Inerting/blanketing liquid storage tanks Reactor feed gases Centrifuge gases Catalyst regeneration Solvent recovery
More informationGas Chromatographic Applications of the Dielectric Barrier Discharge Detector
Gas Chromatographic Applications of the Dielectric Barrier Discharge Detector Matthew Monagle, Advanced Industrial Chemistry Corp*. Ronda Gras, Jim Luong, Dow Chemical Canada 28th International Symposium
More informationRAM Operation Manual
RAM 4021-1 Operation Manual Worldwide Manufacturer of Gas Detection Solutions TABLE OF CONTENTS RAM 4021-1 For Your Safety... 2 Description... 2 Setup Mode... 3 Lights/Alarms... 3 Operation... 4 Calibration...
More informationRAM 4021-DPX Operation Manual
RAM 4021-DPX Operation Manual Worldwide Manufacturer of Gas Detection Solutions TABLE OF CONTENTS ABL 4021-DPX / RAM 4021-DPX For Your Safety... 3 Description... 3 Setup Mode... 4 Lights/Alarms... 4 Operation...
More informationQuantitative Analysis of Hydrocarbons by Gas Chromatography
Quantitative Analysis of Hydrocarbons by Gas Chromatography Introduction Gas-liquid chromatography (GLC) accomplishes a separation by partitioning solutes between a mobile gas phase and a stationary liquid
More informationCHM Gas Chromatography: Our Instrument Charles Taylor (r10)
1/8 Introduction You should already be familiar with the basic concepts of gas chromatography. The purpose of this note pack is to familiarize you with the specific instrument that we will use in our labs.
More informationDiscovery HP-TGA 75/750. Site Preparation Guide
Discovery HP-TGA 75/750 Site Preparation Guide Revision A Issued August 2018 Table of Contents Table of Contents... 2 Ideal Setup... 3 System Components... 4 Instrument Measurements... 5 Utility Requirements...
More informationGas Clean. Filters. Delivering Clean Gases for GC and GC/MS Operation
Gas Clean Filters Delivering Clean Gases for GC and GC/MS Operation Gas Clean Filters Fast, leak-free replacement without tools! Each Gas Clean Filter features a unique quick disconnect design which allows
More informationRAM Operation Manual. Worldwide Manufacturer of Gas Detection Solutions
RAM 4021 Operation Manual Worldwide Manufacturer of Gas Detection Solutions TABLE OF CONTENTS RAM 4021 For Your Safety... 2 Description.... 2 Setup Mode.... 2 Lights/Alarms.... 3 Operation.... 4 Calibration....
More informationMETHOD 21 - DETERMINATION OF VOLATILE ORGANIC COMPOUND LEAKS. 1.2 Scope. This method is applicable for the
1151 METHOD 21 - DETERMINATION OF VOLATILE ORGANIC COMPOUND LEAKS 1.0 Scope and Application. 1.1 Analytes. Analyte Volatile Organic Compounds (VOC) CAS No. No CAS number assigned 1.2 Scope. This method
More informationBest Practice for Identifying Leaks in GC and GC/MS Systems
Best Practice for Identifying Leaks in GC and GC/MS Systems Technical Overview Maintaining a leak-free GC or GC/MS system is critical for obtaining optimal system performance with reliable, reproducible,
More informationThe HumiSys. RH Generator. Operation. Applications. Designed, built, and supported by InstruQuest Inc.
The HumiSys RH Generator Designed, built, and supported by InstruQuest Inc. Versatile Relative Humidity Generation and Multi-Sensor System The new HumiSys with single or dual RH probes capabilities is
More informationDissolved Oxygen Guide
Educat i onser i es Di ssol vedoxygengui de Dissolved Oxygen Guide Introduction Dissolved oxygen probes provide a convenient approach to essentially direct measurement of molecular oxygen. The membrane
More informationCHAPTER 16 %UHDWKLQJ*DV0L[LQJ3URFHGXUHV
CHAPTER 16 %UHDWKLQJ*DV0L[LQJ3URFHGXUHV 16-1 INTRODUCTION 16-1.1 Purpose. The purpose of this chapter is to familiarize divers with the techniques used to mix divers breathing gas. 16-1.2 Scope. This chapter
More informationRAM Operation Manual. Worldwide Manufacturer of Gas Detection Solutions
RAM 4021 Operation Manual Worldwide Manufacturer of Gas Detection Solutions TABLE OF CONTENTS RAM 4021 For Your Safety... 2 Description.... 2 Setup Mode.... 2 Lights/Alarms.... 3 Operation.... 4 Calibration....
More informationAutomated Determination of Dissolved Gases in Water Anne Jurek. Abstract: Discussion:
Automated Determination of Dissolved Gases in Water Anne Jurek Abstract: The RSK-175 standard operating procedure was developed in order to determine the amount of dissolved gas in water. Due to the expansion
More informationLaboratory Hardware. Custom Gas Chromatography Solutions WASSON - ECE INSTRUMENTATION. Engineered Solutions, Guaranteed Results.
Laboratory Hardware Custom Gas Chromatography Solutions Engineered Solutions, Guaranteed Results. WASSON - ECE INSTRUMENTATION Laboratory Hardware Wasson-ECE Instrumentation offers hardware-only solutions
More informationCommercial Practice Test Method Internal Vapor Analysis of Hermetic Devices
Commercial Practice Test Method Internal Vapor Analysis of Hermetic Devices Oneida Research Services, Inc. 8282 Halsey Road Whitesboro, NY 13492 Phone: (315) 736-5480 FAX: (315) 736-9321 1.0 Purpose The
More informationPegas 4000 MF Gas Mixer InstructionManual Columbus Instruments
Pegas 4000 MF Gas Mixer InstructionManual Contents I Table of Contents Foreword Part I Introduction 1 2 1 System overview... 2 2 Specifications... 3 Part II Installation 4 1 Rear panel connections...
More informationRAM 4021-PR. Operation Manual. Worldwide Manufacturer of Gas Detection Solutions
RAM 4021-PR Operation Manual Worldwide Manufacturer of Gas Detection Solutions TABLE OF CONTENTS RAM 4021-PR For Your Safety... 2 Description.... 2 Setup Mode.... 2 Lights/Alarms.... 3 Operation.... 4
More informationAdvantages of Carrier Gas Leak Detection using Novel Helium or Hydrogen Leak Detectors with Specific Sensor Types
19 th World Conference on Non-Destructive Testing 2016 Advantages of Carrier Gas Leak Detection using Novel Helium or Hydrogen Leak Detectors with Specific Sensor Types Klaus HERRMANN 1, Daniel WETZIG
More informationSRI Multi Gas Analyzer 2016
1 SRI Multi Gas Analyzer 2016 TCD for 200ppM-50% Methaniser-FID to low ppm H2 analysis requires Ar Carrier Designs are cost compromised Multiple Columns require Technical Understanding and chromatogram
More informationOver 20,000 Strain Gage Target flowmeters installed since 1952.
Over 20,000 Strain Gage Target flowmeters installed since 1952. Liquid, gases, superheated and saturated steam from -320 to 500 O F and up to 15,000 psi. No frictional moving parts. Designed to withstand
More informationMD61 Thermal Conductor Gas Sensor
MD61 Thermal Conductor Gas Sensor Overview MD series gas sensor is designed on principle of the total thermal coefficient for mixture gas varies with the variant target gas content. It consists of detecting
More informationZebron Gas Management
Zebron www.phenomenex.com/gasmanagement What are the key benefits of Zebron filters and traps? The high adsorption capacity of the Zebron Filters removes contaminants from mobile phase gases, reducing
More informationThermo Scientific Model 146i Principle of Operation
Thermo Scientific Model 146i Principle of Operation The Model 146i Multi-gas Calibrator dilutes calibration gases to precise concentrations. The diluted gases are used to perform zero, precision and Level
More informationModulating Valves for Atmospheric, Infrared, and Direct Fired Burners
BULLETIN MT2035-07/05 Modulating Valves for Atmospheric, Infrared, and Direct Fired Burners M/MR Series M411, M511, M611 M420, M520, M620, MR410, MR510, MR610 MR212D, MR212E, MR212G and MR212J (Flanged),
More informationINSTRUMENTS A THERMAL MASS FLOW SENSOR USING A CONSTANT DIFFERENTIAL TEMPERATURE ABOVE THE AMBIENT GAS TEMPERATURE
TELEDYNE HASTINGS TECHNICAL PAPERS INSTRUMENTS A THERMAL MASS FLOW SENSOR USING A CONSTANT DIFFERENTIAL TEMPERATURE ABOVE THE AMBIENT GAS TEMPERATURE Proceedings of FEDSM 98 1998 ASME Fluids Engineering
More informationAdvancements in Gas Chromatography Analyzers - Keeping up with New Technology. Chuck Runkle Gas Phase Product Specialist ASTS June 2013
Advancements in Gas Chromatography Analyzers - Keeping up with New Technology Chuck Runkle Gas Phase Product Specialist ASTS June 0 Capillary Flow Technology -- solves difficult application problems easily
More informationMACH ONE MASS FLOW CONTROLLER. MACH ONE SERIES flow control. MASS FLOW CONTROLLERS at the speed of sound.
MACH ONE MASS FLOW CONTROLLER MACH ONE SERIES flow control MASS FLOW CONTROLLERS at the speed of sound. MACH ONE SERIES MASS FLOW CONTROLLER FLOW CONTROL AT THE SPEED OF SOUND The Mach One revolutionary
More informationCover Page for Lab Report Group Portion. Pump Performance
Cover Page for Lab Report Group Portion Pump Performance Prepared by Professor J. M. Cimbala, Penn State University Latest revision: 02 March 2012 Name 1: Name 2: Name 3: [Name 4: ] Date: Section number:
More informationanalytical bulk flow distance FLOW level pressure temperature industrial communication
analytical bulk flow distance level pressure temperature industrial communication isolv THERMAL MASS METER Measuring Principle Self-heated Sensor Reference Sensor isolv Thermal Mass Flow Meters have two
More informationO3 3E 1 F Gas Sensor Module
Product Information Pack O3 3E 1 F Gas Sensor Module (Ozone) CONTENTS Product Data Sheet Product Specification 2 Poisoning and Cross Sensitivities 3 Operating Instructions Introduction 4 Electrostatic
More informationApplied Technology and Best Practices in CEE. Conference
Geoinform Applied Technology and Best Practices in CEE Conference THE DEVELOPMENT OF MUD GAS LOGGING SYSTEMS AND THEIR ROLE IN HYDROCARBON EXPLORATION Sándor Pugner GEOINFORM Ltd. Budapest, 17 November
More informationOptimizing Gas Supply for Industrial Lasers
Optimizing Gas Supply for Industrial Lasers Laser cutting of metals and other materials has grown rapidly due to developments in laser power, advancements in CNC automation, and decreasing costs. The industrial
More informationDetecting Hydrogen in Helium Streams. Samuel Goodman. Pittsford Mendon High School. Rochester, New York. Advisor: Dr.
1 Detecting Hydrogen in Helium Streams Samuel Goodman Pittsford Mendon High School Rochester, New York Advisor: Dr. Walter Shmayda Laboratory for Laser Energetics University of Rochester Rochester, New
More informationSuper-Clean Gas Filters from Restek
Super-Clean Gas Filters from Restek Chromatography Products www.restek.com 800-356-688 84-353-300 regulator instrument-grade tubing on/off valve GC carrier gas moisture trap hydrocarbon trap high-capacity
More informationAMS 6916 Board mount pressure sensor with ratiometric analog output
FEATURES Piezoresistive pressure sensor with amplified analog output Calibrated and temperature compensated Ratiometric voltage output, 0.5 4.5 V Digital signal conditioning, 12 bit output resolution Differential,
More informationOxygen Measurement in Natural Gas
Oxygen Measurement in Natural Gas Application Background Natural Gas Fuel is primarily methane. If it were pure methane, it would be very simple to transport and use. But it comes out of the well as a
More informationFlare Gas Composition Analysis and QA/QC Lessons Learned and Lessons Lost SPECTRUM ENVIRONMENTAL SOLUTIONS, LLC 1
Flare Gas Composition Analysis and QA/QC Lessons Learned and Lessons Lost HERMAN HOLM SPECTRUM ENVIRONMENTAL SOLUTIONS, LLC 4C CONFERENCE APRIL 2018 SAN ANTONIO, TX SPECTRUM ENVIRONMENTAL SOLUTIONS, LLC
More informationOXY Integral. INTERCON ENTERPRISES INC Tel: Fax: Internet:
OXY Integral INTERCON ENTERPRISES INC Tel: 800 665 6655 Fax: 604 946 5340 E-Mail: sales@intercononline.com Internet: www.intercononline.com Manual Integral 2006 1 INDEX 2-3 PREFACE 4 INTRODUCTION 5 Principle
More informationMass Flow Controller (MFC) for Gases
Mass Flow Controller (MFC) for Gases Type 8713 can be combined with... Direct flow measurement by MEMS- Technology for nominal flow rates from 1 ml N /min to 8 l N /min (N 2 ) High accuracy and repeatability
More informationHumiSys HF High Flow RH Generator
HumiSys HF High Flow RH Generator Designed, built, and supported by InstruQuest Inc. Versatile Relative Humidity Generation and Multi-Sensor System The HumiSys HF is a high flow version of the previously
More informationLaboratory Hardware. Custom Gas Chromatography Solutions WASSON - ECE INSTRUMENTATION. Custom solutions for your analytical needs.
Laboratory Hardware Custom Gas Chromatography Solutions Custom solutions for your analytical needs. Laboratory Hardware Wasson-ECE Instrumentation offers hardware-only solutions for advanced chromatography
More informationSimplified Backflush Using Agilent 6890 GC Post Run Command Application Note
Simplified Backflush Using Agilent 6890 GC Post Run Command Application Note Gas Chromatography Author Matthew S. Klee Agilent Technologies 2850 Centerville Road Wilmington, DE 19808-1610 USA Abstract
More informationAMS 2710 PCB pressure sensor module with V output
FEATURES Universal pressure sensor module with 0.. 10 V voltage output Fully calibrated and temperature compensated sensor module Variants for (bidirectional) differential, gage, absolute and barometric
More informationOverview. Front Panel: Keypad and Display
Overview The GA-200B is an analyzer that integrates a gas sampling system with sensors to measure and display the concentrations of oxygen and carbon dioxide in a sample as the percentage of a gas in the
More informationCHE 4115 Chemical Processes Laboratory 2 Experiment 1. Batch Distillation
CHE 4115 Chemical Processes Laboratory 2 Experiment 1 Batch Distillation BACKGROUND Distillation is one of the most commonly used unit operations in chemical engineering. In general, a distillation operation
More information