gas chromatography gc
TRANSCRIPT
1Gamal A. Hamid
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• Introduction
• Theory
• Hardware
Injector
Column
Detector
Oven
Carrier gas
• Sample preparation
• Analysis
• Applications
▫ Environmental
▫ Oil and Gas
▫ Food
▫ Pharmaceutical
▫ Forensic / Clinical
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Experience has shown that maximum value can be derived from a scientific instrument
if there is
one person who has a major responsibility for the instrument.
We recommend that you designate a key operator to manage the operation and
maintenance of the TRACE system. We also recommend that the key operator
receive training .
Declaration
Thermo Finnigan Italy
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• A separation technique in which the mobile
phase is a gas. Gas chromatography is always
carried out in a column.
• Separating mixtures of gases or volatile
materials based primarily on their physical
properties.
• It gives both
1- Quantitative
2-Qualitative
Gas Chromatography
GasGas ChromatographyChromatography
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Major Current GC Markets
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Theory
Components of mixture carried in the mobile phase are differentially attracted to the
stationary phase and thus Move through the stationary phase at different rates.
Chromatographic separation involves the use of Chromatographic separation involves the use of
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Generally
o Boiling points is The number one factor to consider in
separation of compounds on the GCs.
o Differences in polarity of the compounds is only
important if you are separating a mixture of
compounds which have widely different polarities.
o Column temperature, the polarity of the column, flow
rate, and length of a column are constant .
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Sample Preinjection
Liquid introduction by syringe
▫ Most commonly used technique
▫ Different syringe types manual and automatic
Other techniques and devices
▫ Sampling valve (gas or liquids)
▫ Head-space (liquids or solids)
▫ Purge and trap (water)
▫ Thermal desorption (solids)
▫ SPME (vapours, liquids or solids)
▫ Pyrolizer (solids)
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Manual injection
Syringes are used to introduce a known volume of a liquid or gas samples.
Adaptor can be used to help control the volume injected
Micro Syringes
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Syringe injection
1- Samples should be injected as a plug.
2- Rapid and consistent injection is necessary
in order to obtain Acceptable precision
Injection Volume
1- Liquids 0.1-10 ul is typical
2- Gases 0.5- 5 ml is typical
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Hot Needle injection
1- Draw sample into syringe barrel.
2- Draw 2-3 ul air into barrel.
3- Inset needle into injection port and allow
to heat for a few seconds.
4- Rapidly inject sample and withdraw the needle.
5- This insure that all sample is injected and the hot needle
assists in solvent volatilization.
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Normal injection
1- Rinse the syringe with your sample at least twice .
2- Draw up the suggested amount of sample into the syringe.
3- Pull up about 1-2 ul of air. This will give a signal showing the beginning of the elution.
4- Insert the needle through the injection port and septum in one movement.
5- Quickly push the plunger.
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Auto sampler
Automatic injection
Sample loading Sample capacity: 8/105 Vials
Max. vial capacity: 2 ml Injections/vial: 0-99
SyringesStandard sampling: 10µlMicro volume sampling: 5µl
Injection parametersMax volume: 5µlMin. Volume : 0.1µlIncrements: 0.1µl stepsViscosity Delay: Yes/No
AS 3000
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TriPlus Autosamplers
Auto sampler
Large sample vial capacity - Max 2 trays installed simultaneously 1, 2 and 2.5 ml vials (up to 300 vials) Syringe size: - 5, 10, 100 and 250 µl. Self recognized - syringes and trays washing station: - 4 x 10ml or 2 x 100ml; multiple solvent rinsing supported
Rapid Mode: Allows to perform cleaning operations
during GC run or cooling time.
Suitable for Ultra Fast GC requirements, eliminating dead times between
successive runs.
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Manual Sampling valve (gas)
Other techniques
In quantitative gas chromatographic determination of a gas mixture, the sample must be introduced in reproducible amounts .
This device, shown in Figure allows to introduce a precise amount of gas sample into the chromatographic column with a simple rapid operation.
Principle For manual gas sampling, a 6-port valve is used.
A wide range of sampling loops allows the injections of different volumes of sample. The switching from load sample to inject sample position (and vice-versa) is performed by rotating the valve rotor knob manually.
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Head Space
Head-space gas analysis
- Volatiles reach equilibrium at STP
- An aliquot of headspace is total in liquid and gas phase
- Conc. in gas proportional Conc. In liquid phase
With headspace matrix left behind
- Clean and gentle chromatography representative of sample
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1- Determination of residual volatile solvents in pharmaceutical
2- Blood alcohol analysis – AN9140
3- Determination of volatile hydrocarbons in waste water
4- Determination of di-acetyl and dichetones in beers
5- Monomers in polymers determination
6- Determination of out-gassing solvents from packages
7- Flavor profiles in drinking beverages or foods (cheese)
Head-space applications
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Cold and trap
allows the analysis of trace of compounds in large volumes
of gaseous samples.
the column can be cooled down to -150 °C by the action of
the liquid nitrogen,
so to trap (i.e. to reconcentrate) the volatile compounds
contained in the sample.
When the trapping is completed, the tube is heated with a
fast temperature programming rate (°C/s), reaching
temperatures up to 400 °C, so to transfer
the trapped compounds into the analytical column.
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GC Basic Components
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The injection port Is a hollow, heated, glass-lined cylinder .
1- The injector is heated so that all
components in the sample will be vaporized.
2- If the temperature is too low, separation is poor and
broad spectral peaks should result or no peak develops at all.
3- If the injection temperature is too high, the
specimen may decompose or change its structure.
4- The temperature of the sample port is usually
about 50°C higher than the boiling point of the least volatile component
of the sample.
1 .Injector
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Vaporizing.
The liquid sample is evaporated prior to be transferred to the
separation column
▫ Split Spliless: SSL (permanently hot)
▫ Programmed Temperature Vaporizer: PTV
▫ Direct: PKD, PPKD (permanently hot, low resolution columns)
Nonvaporizing.
The liquid sample evaporates into the separation column (or a
precolumn)
▫ Cold On Column: OC (permanently cool)
Injection techniques
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Injector types
1. Split/ Splitless Injector
2. On-Column Injector
3. High Oven Temperature On-Column Injector
4. Large Volume On-Column Injector
5. Packed Column Injector
6. Purged Packed Injector
7. Programmable Temperature Vaporizing Injector
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• Split mode
1. The split vent is open, part of the sample go into the column.
2. When analyzing high concentration or neat samples.
3. Yields the sharpest peaks if the split gas is properly mixed.
4. Standard for capillary columns.
1. Split/Splitless Injector (vaporising injector)
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Splitless mode
1. The split vent is closed, most of the sample go into the column.
2. When analyzing low concentration or diluted samples.
3. Splitless times of ~ 1 minute are typical.
4. Standard for capillary columns.
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Non- vaporising injectors
1. The sample is transferred as a liquid directly inside the column
under the oven temperature control. The sample evaporation takes
place inside the column.
2. Sample doesn’t come in contact with any “column-external” device
3. No vaporization step at a temperature above that of the column
2. On-Column Injector
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• Primary cooling
▫ Permanently active fan
▫ Keep the injector head at room temperature independently from oven temperature
• Secondary cooling
▫ Temporary stream of compressed air
▫ Avoid evaporation from the needle even at oven T close or slightly higher than BP
▫ Reduces the length of the flooded zones
▫ Avoid liquid backflow reducing the vapor pressure at the plug front
▫ More eefficient and rapid cooling of the injector base after a temperature ramp
• Cooling Time The amount of time the secondary cooling stays on after the start the injection.
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1- The OCI is the same as the regular cold on column except that a cooling
jacket is installed in the GC oven around the head of the column.
2- This allows a cold on column injection with a high oven temp.
Temperature (°C).
1- The temp. checkbox checked for this option to be used.
2- This specifies cooling jacket temp. during injection.
3- Duration (min) the duration of the jacket cooling from the start of the run
3. High Oven Temperature On-Column Injector
4. Large Volume On-Column Injector
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1. Injection directly into metal or glass packed columns with
or without glass liner.
2. The temp. is usually selected to be 20 ºC above the
evaporation temp. for all sample.
3. Optimum temp. varies with the method and sample
requirements.
5. Packed Column Injector
6. Purged Packed Injector
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7. Programmable Temperature Vaporizing Injector
1. Can vary the temp. during injection in both split and Splitless.
2. Can eliminate many of the unwanted effects , such as distillation of the sample
within the needle and large vapor clouds inside injector chamber.
3. In Constant Temperature (CT) mode, the PTV functions like a split/splitless injector.
4. Sample volumes are lower than when using S/SL injector because of the smaller
PTV liner volume .
5. Can analyze relatively dirty samples that can not be analyzed using a traditional on-
column technique.
PTV Injector
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1. Determination of residual volatile solvents in pharmaceutical
2. Blood alcohol analysis – AN9140
3. Determination of volatile hydrocarbons in waste water
4. Determination of di-acetyl and dichetones in beers
5. Monomers in polymers determination
6. Determination of out-gassing solvents from packages
7. Flavor profiles in drinking beverages or foods (cheese)
Head-space applications
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Good injector
1. Capable to quantitative accept a broad volatility range of sample components .
2. Low discrimination.
3. To handle dirty and clean matrices.
4. With dirty matrices reduces sample clean-up and preserves the column.
5. With clean matrices boosts sensitivity with LVI techniques .
6. Extremely inert.
7. Able to handle polar/active compounds.
8. Provide optimum band shape.
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GC Basic Components
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The column
• is where the chromatographic separation of the sample occurs.
• Several types of columns are available for different chromatographic
applications:
• The heart of the system.
• It is coated with a stationary phase which greatly influences the
separation of the compounds.
2 .Column
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Stationary phase
Solid resin packed in a column , or
Liquid supported by course paper or
Inactive solid over which a mixture passes.
Each component of the mixture differs in the way it adheres to this phase
and therefore travels along it at a unique rate.
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There are two types of packing employed in GC, the adsorbents and the supports, on which
the stationary phase is coated.
There are both inorganic and organic types of adsorbents.
•Alumina, in an activated form, is used to separate the permanent gases and hydrocarbons
up to about pentane.
•Silica gel It is used for the separation of the lower molecular weight gases and some of the
smaller hydrocarbons sulfur gases, hydrogen sulfide, sulfur dioxide and carbon disulfide.
•Synthetic zeolites used for the separation of hydrogen, oxygen, nitrogen, methane and
carbon monoxide and also rare gasses.
The Adsorbents
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POLYSILOXANES
• The most common stationary phases.
• They are available in the greatest variety and are the most stable, robust and
versatile.
• The most basic Polysiloxanes is the 100% methyl substituted
POLYETHYLENE GLYCOLS
• They are less stable, less robust and have lower temperature limits than most
Polysiloxanes.
• must be liquids under GC temperature conditions.
Types of stationary phaseLiquid supported
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• There have been a number of materials used as supports for
packed GC columns including,
• Celite (a proprietary form of a diatomaceous earth), fire-
brick (calcined Celite), fire-brick coated with metallic silver
or gold, glass beads, Teflon chips and polymer beads.
• polystyrene beads
Inactive solid supports
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Column types
1- Conventional 1/8-1/4 OD 6-8 feet in length Stainless steel or glass tube
2- Preparative >1/4 OD > 10 feet in length
2- Capillary 0.1- 0.5 ID 10 – 100 meters in length
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Volatility of compound: Low boiling (volatile) components will
travel faster through the column than will high boiling components
Polarity of compounds: Polar compounds will move more slowly,
especially if the column is polar.
Column temperature: Raising the column temperature speeds up
All the compounds in a mixture.
Columns have lower and upper temperature limits.
Factors affecting column separations
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Column packing polarity: Usually, all compounds will move slower on
polar columns, but polar compounds will show a larger effect.
Flow rate of the gas through the column: Speeding up the carrier gas
flow increases the speed with which all compounds move through the
column.
Length of the column: The longer the column, the longer it will take all
compounds to elute. Longer columns are employed to obtain better
separation.
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Boiling points is The number one factor to consider in separation of
compounds on the GCs.
Differences in polarity of the compounds is only important if you are
separating a mixture of compounds which have widely different polarities.
Column temperature, the polarity of the column, flow rate, and
length of a column are constant .
Generally
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1- Contaminated column.
2- Damaged stationary phase.
3- Different column temperature, carrier flow rate or column.
4- Large changes in the sample concentration.
5- Improper injector operation.
Loss of Separation or Resolution
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Column Damage
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It is the continuous elution of the compounds produced
from normal degradation of the stationary phase.
is the background generated by all columns
Column bleed increases at higher temperatures.
Column Bleed
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1. Exposure of the column to air (oxygen) .
2. Exceeding the upper temperature limit of the column
for prolonged periods.
3. Chemical damage.
4. Contamination of the column with high molecular weight materials.
5. Column breakage.
Rapid Column Deterioration
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GC Basic Components
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1. The use of a temperature programme for the column oven
influences the separation process significantly and is used for
optimization of time and peak separation.
2. The oven must not be opened when the oven temperature is
above room temperature.
3. Never turn off the nitrogen flow unless the column and oven are
at room temperature.
3 .Oven
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• Temperature range 5 °C above ambient to 350 °C
• Temperature programming - up to six ramps
• Maximum run time - 999.99 minutes
• Temperature ramp rates - 0 to 120°C/min
• The oven accommodates one inlet, one detector,
and one column.
The Oven capabilities
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A multiple-ramp temperature program changes the oven temperature
from an initial value to a final temperature, but with various rates, times,
and temperatures in between.
Multiple ramps can be programmed for temperature decreases as well as
Increases.
Multiple-ramp temperature programs
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GC Basic Components
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4 .Detector
The part of a gas chromatograph which signals the
change in composition of the mixture passing through it.
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Detector types
1. Electron Capture Detector.
2. Flame ionization Detector.
3. Nitrogen Phosphors Detector.
4. Thermal Conductivity Detector.
5. Flame Photometric Detector.
6. Photo ionization Detector.
7. Electrolytic Conductivity Detector.
8. Mass Spectrometric Detector.
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Mechanism:
Electrons are supplied from a 63Ni foil lining the detector cell. A current is generated in the cell. Electronegative compounds capture electrons resulting in a reduction in the current. The amount of current loss is indirectly measured and a signal is generated.
Selectivity: Halogens, nitrates and conjugated carbonylsSensitivity: 0.1-10 pg (halogenated compounds); 1-100 pg (nitrates); 0.1-1 ng (carbonyls)Linear range: 1000-10000 Gases: Nitrogen or argon/methaneTemperature: 300-400°C
1 .Electron Capture Detector( ECD)
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Mechanism:
Compounds are burned in a hydrogen-air flame. Carbon containing compounds produce ions that are attracted to the collector. The No. of ions hitting the collector is measured and a signal is generated.
Selectivity: Compounds with C-H bonds. A poor response for some non-hydrogen containing organics (e.g., hexachlorobenzene). Sensitivity: 0.1-10 ngLinear range: 105-107Gases: Combustion hydrogen and air; Makeup He or N2Temperature: 250-300°C,and 400-450°C for high temp.
2 .Flame ionization Detector( FID)
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3 .Nitrogen Phosphors Detector( NPD)
Mechanism:
Compounds are burned in a plasma surrounding a rubidium bead supplied with hydrogen and air. Nitrogen and phosphorous containing compounds produce ions that are attracted to the collector. The number of ions hitting the collector is measured and a signal is generated.
Selectivity: Nitrogen and phosphorous Containing compoundsSensitivity: 1-10 pgLinear range: 104-10-6Gases: Combustion - hydrogen and air; Makeup - HeliumTemperature: 250-300°C
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Mechanism:
A detector cell contains a heated filament with an applied current. As carrier gas containing solutes passes through the cell, a change in the filament current occurs. The current change is compared against the current in a reference cell. The difference is measured and a signal is generated.
Selectivity: All compounds except for the carrier gasSensitivity: 5-20 ngLinear range: 105-106 Gases: Makeup - same as the carrier gasTemperature: 150-250°C
4.Thermal Conductivity Detector( TCD)
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Mechanism:
Compounds are burned in a hydrogen-air flame. Sulfur and phosphorous containing compounds produce light emitting species (sulfur at 394 nm and phosphorous at 526 nm). A monochromatic filter allows only one of the wavelengths to pass. A photomultiplier tube is used to measure the amount of light and a signal is generated. A different filter is required for each detection mode.
Selectivity: Sulfur or phosphorous containing compounds. Only one at a time.Sensitivity: 10-100 pg (sulfur); 1-10 pg (phosphorous)Linear range: Non-linear (sulfur); 103-105 (phosphorous)Gases: Combustion - hydrogen and air; Makeup - nitrogenTemperature: 250-300°C
5 .Flame Photometric Detector( FPD)
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Mechanism:
Compounds eluting into a cell are bombarded with high energy photons emitted from a lamp. Compounds with ionization potentials below the photon energy are ionized. The resulting ions are attracted to an electrode, measured, and a signal is generated.
Selectivity: Depends on lamp energy. Usually used for aromatics and olefins (10 eV lamp).
Sensitivity: 25-50 pg (aromatics); 50-200 pg (olefins) Linear range: 105-106 Gases: Makeup - same as the carrier gasTemperature: 200°C
6 .Photo ionization Detector( PID)
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Mechanism:
Compounds are mixed with a reaction gas and passed through a high temperature reaction tube. Specific reaction products are created which mix with a solvent and pass through an electrolytic conductivity cell. The change in the electrolytic conductivity of the solvent is measured and a signal is generated. Reaction tube temperature and solvent determine which types of compounds are detected.
Selectivity: Halogens, sulfur or nitrogen containing compounds. Only one at a time.Sensitivity: 5-10 pg (halogens); 10-20 pg (S); 10-20 pg (N)Linear range: 105-106 (halogens); 104-105 (N); 103.5-104(S)Gases: Hydrogen (halogens and nitrogen); air (sulfur)Temperature: 800-1000°C (halogens), 850-925°C (N), 750-825°C (S)
7 .Electrolytic Conductivity Detector( ELCD)
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Mechanism:
Compounds are bombarded with electrons (EI) or gas molecules (CI). Compounds fragment into characteristic charged ions or fragments. The resulting ions are focused and accelerated into a mass filter. The mass filter selectively allows all ions of a specific mass to pass through to the electron multiplier. All of the ions of the specific mass are detected. The mass filter then allows the next mass to pass through while excluding all others. The mass filter scans stepwise through the designated range of masses several times per second. The total number of ions are counted for each scan. The abundance or number of ions per scan is plotted versus time to obtain the chromatogram (called the TIC). A mass spectrum is obtained for each scan which plots the various ion masses versus their abundance or number.
Selectivity: compound gives fragments within mass range.Sensitivity: 1-10 ng (full scan); 1-10 pg (SIM)Linear range: 105-106 Gases: NoneTemperature: 250-300°C (transfer line), 150-250°C (source)
8. Mass Detector
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Good Detector
1. High sensitivity.
2. Rapidly respond to concentration changes.
3. Large linear range.
4. Stable with respect to noise and drift.
5. Low sensitivity to variation in flow,
6. pressure and temperature.
7. Possible selectivity.
8. Produces an easily handled signal.
9. A temperature range from room temperature to at least 400 C.
Properties of a good detector.
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GC Basic Components
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An inert gas, which is used to sweep a mixture to be separated
through a gas chromatograph , (helium, hydrogen, or nitrogen)
1. Push the sample through the gas chromatograph column
2. Clean out the gas chromatograph column after sample analysis
5 .Carrier gas
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The carrier gas
ultra-pure and research-grade gases of up to 99.9999% (Grade 6.0) purity. the carrier gas system often contains a molecular sieve to remove water or other impurities.
Linear Velocity (u)
Is the speed at which the carrier gas or mobile phase travels through the column. The linear velocity is generally expressed in cm/s
- The linear velocity is independent of the column diameter while the flow rate is dependent on the column diameter.
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Helium For carrier gas: 99.995%1 high purity, with less than 1.0 ppm each of
water, oxygen, and total hydrocarbons after purification.
Use water, oxygen, and hydrocarbon traps.
Hydrogen For carrier or detector fuel gas: 99.995%1 high purity, with <
1.0 ppm of total hydrocarbons after purification.
Use water, oxygen and hydrocarbon traps.
Air For detector fuel gas: 99.995%1 high purity.
Air compressors are not acceptable because they do not
meet pressure, water, and hydrocarbon requirements.
Nitrogen For carrier or make-up gas: 99.995% high purity, with less than 1.0
ppm of total hydrocarbons after purification.
Argon/5% Methane For ECD make-up gas: 99.995%1 high purity.
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CAUTION
Do not use liquid soap leak detectors to check for leaks. Liquid soap leak detectors may
contaminate you system. A mixture of 50% H2O/50% methanol or isopropyl
alcohol may be used as a liquid leak detector.
WARNING! Never use liquid leak detectors on or around electronic pneumatic circuits
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Generators
Nitrogen Generator
The nitrogen generator can also operate directly from the laboratory compressed air supply. General contaminants are first removed with appropriate filters and adsorbents and the purified air passes over layers of polymeric hollow fiber membranes through which nitrogen selectively permeates.
Hydrogen Generator
In the Packard Hydrogen Generator, hydrogen is generated electrolytically from pure deionized water.
The electrolysis unit uses a solid polymer electrolyte and thus does not need to be supplied with electrolytes, only the deionized water.
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1. The data recorder plots the signal from the detector over time.
2. The retention time, is qualitatively indicative of the type of compound.
3. the area under the peaks or the height of the peak is indicative of the amount of each
component.
Chromatogram
Chromatogram
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Retention time
• RT, is the time it takes for a compound to
travel from the injection port to the detector
• thousands of chemicals may have the same retention time, peak
shape, and detector response.
• For example, under certain conditions, DDT has the same retention
time as PCBs (polychlorinated biphenyls).
Retention Time (RT)
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Retention Time Shifts
Retention Time Shifts
1. Different column temperature.
2. Different carrier gas flow rate or linear velocity.
3. Leak in the injector, especially the septum.
4. Contaminated column.
5. Change in the sample solvent.
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1. Gases - pressures, carrier gas average linear velocity,
and flow rates (detector, split vent, septum purge).
2. Temperatures - column, injector, detector .
3. System parameters - purge activation times, detector attenuation, mass ranges, etc.
4. Gas lines and traps - cleanliness, leaks, expiration.
5. Injector consumables - septa, liners, O-rings and ferrules.
6. Sample integrity - concentration, degradation, solvent, storage.
7. Syringes - handling technique, leaks, needle sharpness, cleanliness.
8. Data system - settings and connections.
SIMPLE CHECKS
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Sample Preparation
liquid-liquid extraction
liquid-liquid extraction is generally used to move
components from a less volatile liquid to a more
volatile liquid, e.g., from water to methylene chloride.
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liquid-Solid extraction
The soxhlet extractor is used to extract organic
compounds from solids.
The center chamber contains a porous paper thimble .
Inside the thimble is the solid sample to be extracted.
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Properties of injected sample
1. The sample should not be too large,
2 . The compounds are normally gases or they can be
Heated and vaporized into a gaseous state.
3. Non-selective detector responds to all compounds
4. Volatilized in a hot injection chamber
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QA& QC Procedures
The standard sample must be analyzed with the same
instrument, under the same conditions, immediately before
and immediately after analyzing the unknown specimen.
If the resulting three spectral outputs do not agree, the
technician can not make a reliable identification of the
specimen based on the GC analysis.
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Quantitative Analysis
Normalization method does response if:-
1. A portion of the injected sample is not eluted.
2. The detector does not respond to some component of
the sample.
3. Some component is not identified.
4. Some component is not resolved.
5. The response factor of some component is not known.
6. The area of some peak cannot be determined.
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Major Current GC Markets
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Environmental
What is the environmental market?
1. Testing or commercial laboratories
2. Industrial laboratories
3. Government laboratories
4. Research institutes
Requirements of the applications
1. Drinking water
2. High sensitivity Waste
3. Sensitivity and selectivity Air
4. sample introduction
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Clean water analysis
Pollutants in water Halocarbons Acid priority pollutants: phenols,
chlorophenols, nitrophenols Pesticides and PCBs Base neutral priority pollutants Polynuclear aromatic hydrocarbons
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Analysis of Halocarbons in ground water
Column:Precolumn:
Oven Program:
Injection Speed:Solvent Delay Time:Pressure:Extraction mode:
DAI2ECD (MEGA) 30 m x 0.32 mm ID5 µm film thicknessEmpity precolumn 10 m x 0.53 mm IDOV1701 3 m x 0.53 mm ID1 µm film thickness40°C for 2 min (rate 10°C/min)to 70°C for 0,5 min (rate 3°C/min)to 150°C for 0,5 min (rate 20°C/min) to 310°C for 2 min8 µl/sec17 sec65 kPa, He, (constant pressure)7 ml of sample in water(in autosampler vial 10 ml)with 3 ml of Diethyl ethere and mix
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DiChloroMethaneChloroformTriChloroethaneTriChloroEthyleneBromodiChloromethaneTetraChloroEthyleneDiBromoChloroMethaneBromoformioCarbonTetrachlorideDibromoMethane
CompoundsPeaks
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PolyAromatic Hydrocarbons in water
Sample:Vial volume:Sample volume:Inj. speed:Oven temp.:
SVE delay:Precolumn:Column:Detectors:
River water spiked with 2 ppb PAHs (each)10 ml150 µl 5 µl/sec65°C (4 min) up to 250°C (10 min)then to 300°C (10 min) at 5°C/min30 secUNCORET25 m x 0.32 mm ID, SE54, 0.45 µm film thicknessPID (8.4 eV) and FID
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NaphtaleneAcenaphtyleneAcenaphteneFluorenePhenanthreneAnthraceneFluoranthenePyreneBenzo(a)anthraceneChryseneBenzo(b)fluorantheneBenzo(k)fluorantheneBenzo(a)pyreneIndeno(1,2,3-cd)pyreneDibenzo(a,h)anthraceneBenzo(ghi)perylene
CompoundsPeaks
87Gamal A. Hamid
Chlorinated pesticides in ground water
Column:Precolumn:
Oven Program:
PTV Program:
Injection mode:Splitless Time:Split Flow:Pressure:Injection speed:Extraction mode:
SE 52 MS 30 m x 0.25 mm, 0.25 µm f.t.2 m x 0.25 mm ID deactivated anduncoated precolumn150°C for 1 min (rate 6°C/min)to 300°C for 2 min35°C for 30 sec (rate 15°C/sec)to 275°C for 2 minSolvent split1 min100 ml/min95 kPa5 µl/sec7 ml of sample in water(in autosampler vial 10 ml)with 3 ml of diethyl ether and mix
Dieldrinp,p’-DDEEndosulfan IIp,p’-DDDEndrin AldheydeEndossulfan SulfateEndrin KetoneMethoxychlor
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a-BHCb-BHCg-BHCd-BHCHeptachlorAldrinHeptachlor EpoxideEndosulfan I
910121314151718
GC Analysis using PTV Solvent Split /LVI /ECD
88Gamal A. Hamid
Petrochemical and Gas
Large replacement business
Refinery
Oil Industry
Gas suppliers
Requirements of the applications
Multi-valves applications
Fastest possible cycle time
QC of gases: sensitivity
Customized software
Easy to use data handling and reporting
89Gamal A. Hamid
Mineral oil analysis
Analysis of trace of mineral oil in ground water byin vial extraction and large sample volume injection
Solvent:
Column:
Precolumn:
Inj. volume:
Inj. speed:
Inj. temp.:
Inj. pressure:
SVE time:
Oven program:
Petroleum ether
DB1, 30 m x 0.32 mm ID0.25 µm film thickness
UNCORET
200 µl
5 µl/s
45°C
100 kPa
18 s
45°C (3 min) to 320°C(10 min) at 20°C/min
C-10
C-12
C-14
C-16
C-18C-20
C-22C-24
C-26C-28
C-30C-32
0 6 12 18 24 Time (min)
SAMPLEPREPARATION
TriPlussyringe
water
petroleumether
90Gamal A. Hamid
Mineral Oil Analysis
Sample:Column:
Temp. progr.:
Carrier gas:
Inj. mode:Inj. temp:Detector:
0.2 µl of mineral oil15 m x 100 µm ID,SE54 0.15 µm f.t.60°C to 350°C (3 min)at 40°C/minHydrogen at 0.35 ml/minconstant flowsplit (1:400 split ratio)320°CFID at 370°C
Narrow Bore Capillary Column
91Gamal A. Hamid
FID detection of Hydrocarbons
CH4
C2H6
C3H
8
i-C4H10n-C4H10
i-C5H12n-C5H12n-C6H14
Peak area reproducibilityComponents CH4 C2H6 C3H8 iC4 nC4 iC5 nC5 C6+
1998128 142669 215792 296627 308001 40857 41287 423612007363 143282 216169 297831 309222 41377 41847 522232003870 143012 216065 297847 311117 41297 41791 522351997464 142518 215470 296846 308465 40967 41240 52361
Average 2001706 142870.3 215874 297287.8 309201.3 41124.5 41541.25 49795Standard dev 4742.756 343.6145 312.7544 642.8102 1372.734 251.5784 322.1039 4956.393Relative Standard dev % 0.24% 0.24% 0.14% 0.22% 0.44% 0.61% 0.78% 9.95%
92Gamal A. Hamid
Food & Beverages
• Very extended market field
• No really regulated methods
• Ideal market to exploit the TRACE GC modularity
• Requirements of the applications
▫ QC of producers: Sensitivity and rapidity
▫ Multi detection capability
▫ Correct sample inlet (PTV-OC)
▫ Easy to use data handling and reporting
93Gamal A. Hamid
Determination of Fat Content of Foods
GC Analysis of FAME
94Gamal A. Hamid
Pharmaceutical
Highly regulated market (pharmacopeia)
Requires Validation package
Requirements of the applications
• Limited instrument requirements SSL/NPD/FID
• Highly Automated market
• High sensitivity detectors
• A unified chromatography software
95Gamal A. Hamid
pharmaceutical
Application focus
• OV solvent residual in tablets (20%)
• Drugs lab testing (50%)
96Gamal A. Hamid
Antihistaminic Drugs analysisInj. volume:Column:Oven:
Inj. mode:Carrier:Detector:
1 µlOV1, 25m x 0.32 mm ID, 0.15 µm f.t.140°C for 3 min140°C to 230°C at 20°C/min230°C for 2 min230°C to 260°C at 20°C/min260°C for 15 minsplitless (250°C)HeliumNPD (275°C)z
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PheniramineDiphenhydramineTripelennamineCl. PheniramineCyclizineCarbinoxamineBr. PheniramineMianserineMepyraminePromethazine7-Methyl Mianserine (I.S)MeclizineFlunarizineCinnarizine
CompoundsPeaks
97Gamal A. Hamid
Forensic/Medical
Application focus
• Blood Alcohols analysis (20%)
• Breathe oxygen purity (5%)
