Harris: Quantitative Chemical Analysis, Eight Edition CHAPTER 23: GAS CHROMATOGRAPHY
|
|
- Charlotte Newman
- 5 years ago
- Views:
Transcription
1 Harris: Quantitative Chemical Analysis, Eight Edition CHAPTER 23: GAS CHROMATOGRAPHY
2 Chapter 23. Gas Chromatography What did they eat in the year 1,000? GC of Cholesterol and other lipids extracted from British bones (AD 500~1,800)
3 Chapter 23. Gas Chromatography
4 23-1 The Separation Process in Gas Chromatography Mobile phase : Carrier gas (He, H 2, N 2...) Stationary phase : i) nonvolatile liquid on a solid support (gas-liquid partition chromatography) ii) solid particles (gas-solid adsorption chromatography) Analyte : gas or volatile liquid
5 23-1 The Separation Process in Gas Chromatography - The column must be hot enough to provide sufficient vapor pressure for analytes to be eluted in a reasonable time. - The detector is maintained at a higher temperature than the column so that all analytes will be gaseous.
6 23-1 Open Tubular Columns Fig 23-2a Typical dimensions of open tubular gas chromatography column. Fig 23-2b Fused silica column with a cage diameter of 0.2 m and column Length of m.
7 23-1 Open Tubular Columns Fig 23-2c Cross sectional view of open tubular column.
8 23-1 Open Tubular Columns
9 -Narrow columns provide higher resolution than wider columns, but require higher operating pressure and have less sample capacity
10 Resolution is proportional to then square root of plate number or to the column length
11 - Increasing thickness (0.25 to 1.0 um) increases retention time and thus increases resolution of early eluting peaks.
12 The choice of liquid stationary column like dissoves like
13 Common Stationary Phases
14 Choice of liquid stationary phase like dissolves like rule - Nonpolar columns are best for the nonpolar solutes. - Intermediate columns are best for the intermediate solutes. - Polar columns are best for the polar solutes.
15
16 23-1 The Separation Process in Gas Chromatography : Packed Columns Packed columns : - Stationary phase : i) Fine particles of solid support coated with nonvolatile liquid ii) or Fine particle itself - Comparison of packed column with open tubular column 1) Weak points of packed column : i)broader peaks, ii) longer retention times, iii) lower resolution 2) If uniform particle size smaller multiple path term If small particle size smaller equilibration time term but, needs higher pressure 3) Strong point : larger capacity due to a great deal of stationary phase useful for preparative separations which require a great deal of stationary phase or to separate gases that are poorly retained.
17 Fig Chromatogram of alcohol mixture using Packed Column poor resolution
18 23-1 The Retention Index * The relative retention times (t r ) of polar and nonpolar solutes change as the polarity of the stationary phase changes : 1) Non-polar stationary phase : the order of volatility of the solutes (Fig.23-9a) 2) polar stationary phase strongly retain the polar solutes Alcohols (3, 6, 9) > Ketones (1, 4, 7) > Alkanes (2, 5, 8, 10) (Fig. 23-9b)
19 Fig Separation of 10 compounds on a) Nonpolar and b) Strongly polar 1 um thick stationary phase in open tubular column at 70 0 C.
20 23-1 Temperature and Pressure Programming Temperature programming : the temperature of a column is raised during separation to increase solute vapor pressure. 1) It decreases retention time of late- eluting components. 2) It sharpens peaks. *Avoid raising the temp. so high that analytes and stationary phase decompose. Pressure programming : The inlet pressure increases to increase the flow of mobile phase. 1) It decreases retention time of late- eluting components. 2) The pressure can be rapidly to the initial value for the next run, whereas in temperature programming, time is wasted waiting for a hot column to cool before the next injection. 3) Programmed pressure is useful for analytes that cannot tolerate high temperature.
21 Figure. Comparison of a) Isothermal (constant) and b) programmed temperature chromatography of linear alkanes.
22 Figure. Comparison of a) Isothermal (constant) and b) programmed temperature chromatography of linear alkanes. - At a constant temperature of C, the more volatile compounds emerge close together, and less volatile compounds may not even be eluted from the column.
23 Figure. Comparison of a) Isothermal (constant) and b) programmed temperature chromatography of linear alkanes. - If the temperature increases from 50 0 C to C at a rate of 8 0 C /min, all compounds are eluted and the separation of peaks is fairly unifrom.
24
25 23-1 Carrier Gas H A + B u x + Cu x [22-33] mass transfer = Cux = ( Cs + H C ) u m x [22-35] C s = 3( k 2k + 1) 2 d D 2 s (22 35a) C m = 1+ 6k 24( k + 11k + 1) 2 2 r D 2 m (22 35b) If the stationary phase is thin enough ( <0.5 um), mass transfer is dominated by slow diffusion through the mobile phase rather than through the stationary phase. In other words, C s << C m in eqs a & b. -For a column of a given radius, r, and a solute of a given retention factor k, the only variable affecting the rate of mass transfer in the mobile phase is the diffusion coefficient of solute through the mobile phase. (Diffusion coefficients of solute: H 2 > He > N 2 ) decrease in C m (eq b)
26 23-1 Carrier Gas (Diffusion coefficients of solute: H 2 > He > N 2 ) decrease in C m (eq b) - H 2, He and N 2 give the same optimal plate height (0.3 mm) at different flow rates. - H 2, He give better resolution (smaller H) than N 2 at high flow rate because solute diffuse more rapidly through H 2, He than through N 2. - Faster separation can be achieved with H 2 as a carrier gas, and H 2 can be run much faster than its optimal velocity with little penalty in resolution. Fig Van Deemter curves for GC of n-c 17 H 36 at C
27 Fig Separation of two polyaromatic hydrocarbons on a open tubular column with different carrier gases. - As the carrier gas changed from N 2 to He to H 2, resolution increased and analysis time decreased. - H 2 : speed of analysis (advantage), good column efficiency : dangerous (explosive with air) and reactive (hydrogenation of C=C bonds) at elevated temp. He : good alternative for H 2
28 23-3 Detectors
29 23-3 Detectors Thermal Conductivity Detector (TCD) Filament; hot tungsten (w)-rhenium (Re) filament Stream; Analyte of different thermal conductivity + carrier gas (He)
30 23-3 Detectors The thermal conductivity of the mixed stream decrease because He has the second highest thermal conductivity (next slide). The filament gets hotter. Its electrical resistance increases. The voltage drop through the filament changes. The detector (TCD) measures the change in voltage
31 Thermal Conductivity Detector (TCD) Remark : i) The thermal conductivity (TC) of H 2 and He = 6 ~ 10 times greater than those of most organic compounds. Consequently, the detector undergoes a relatively large decrease in TC even at the presence of small amount of organic materials. ii) H 2 and He give the lowest detection limit.
32 Thermal Conductivity Detector (TCD) Remark : iii) Sensitivity increases with increasing filament current decreasing flow rate decreasing detector surrounding block temp. iv) In the past, TCD was the most common in GC because they are simple and universal. v) It s not sensitive enough to detect minute quantities of analytes.
33 Flame Ionization Detector (FID) - Most organic compounds, when pyrolyzed at the temp. of H 2 /air flame, produce CH radicals, which are thought to produce CHO + ions in the flame. CH radicals + O CHO + + e - - The charged species (CHO + ) are attracted to and captured by a collector. - The ion current that results is then amplified and recorded.
34 Flame Ionization Detector (FID) - In the absence of organic solutes, the current is almost zero. (The ionization in a flame is a poorly understood process) - Only about 1 in 10 5 carbon atoms produces an ion, but ion production is strictly proportional to the number of susceptible carbon atoms entering the flame.
35 Flame Ionization Detector (FID) Remark : i) FID is insensitive to noncombustible gases (N 2, O 2, H 2 O, CO 2, SO 2, H 2 S, No x, etc) These properties make FID a useful general detector for most organic samples, including those contaminated with water and the oxides of nitrogen and sulfur. ii) Advantages high sensitivity ( g/ml), The detection limit is ~100 times smaller than TCD. The detection limit is further reduced by 50 % when N 2 is used instead of He (N 2 gives best detection limit ). large linear response ( 10 7 ), low noise, ruggedness convenience iii) Disadvantages destroy the sample
36 Electron Capture Detector (ECD) * Most detectors other than FID and TCD respond to much more limited classes of analytes. Electron Capture Detector (ECD) - Carrier gas : N 2 or 5% CH 4 in Ar. (Moisture decrease sensitivity) - A gas (or effluent from the column) is passed over a beta emitter (Ni 63 or H 3 ). An electron from the emitter causes ionization of the carrier gas and production of a burst of electrons.
37 Electron Capture Detector (ECD) - Electrons thus formed are attracted to an anode, producing a small steady current, - However, in the presence of analyte molecules with a high e - affinity which capture some of the electrons, the current decreases. - The ECD responds by varying the frequency of voltage pulses between the anode and cathode to maintain a constant current.
38 Electron Capture Detector (ECD) - Remark : i) Highly sensitive to electronegative functional groups (halogens, conjugated C=O, -C N, -NO 2, -O-O-) See detection limit in Table ii) Insensitive to compounds (amine, alcohols, hydrocarbons) iii) Application : detection of chlorinated pesticides iv) Advantage : Not consuming the sample to any significant extent
39 Fig.. Partial gas chromatogram using an ECD to measure halogenated compounds (green house gases) in the air at an altitude of 800 m.
40 Flame Photometric Detector (FPD) - Eluate from the column passes through a H 2 -Air flame - Excited atoms (S, P, Pb, Sn. etc.) emit characteristic light - P (536 nm), S (394 nm) emission is isolated by a narrow-band interference filter and detected with a photo multiplier tube - Application: For example, detection of pesticides containing P & S
41 Sulfur Chemiluminescence Detector - It takes the exhaust from FID detector where S compound H 2 -O 2 flame FID SO + Products - Mixing it with ozone to form an excited state of SO 2. SO + O 3 SO 2 * + O 2 _- Excited state of SO 2 emits blue light and UV. SO * 2 SO 2 + hν (emission of blue light and U.V.) Emission intensity mass of S in sample - A Nitrogen Chemiluminescence Detector works in an analogous manner times greater sensitivity to S or N than to hydrocarbons.
42 Fig Gas chromatograms showing sulfur compounds in natural gas. a) FID, b) sulfur chemiluminescence detector.
43 23-3 Detectors
Chapter 27: Gas Chromatography
Chapter 27: Gas Chromatography Gas Chromatography Mobile phase (carrier gas): gas (He, N 2, H 2 ) - do not interact with analytes - only transport the analyte through the column Analyte: volatile liquid
More informationGas chromatography. Advantages of GC. Disadvantages of GC
Advantages of GC Gas chromatography Fast analysis, typically minutes Effi cient, providing high resolution Sensitive, easily detecting ppm and often ppb Nondestructive, making possible on - line coupling;
More informationGas Chromatography. Introduction
Gas Chromatography Introduction 1.) Gas Chromatography Mobile phase (carrier gas) is a gas - Usually N 2, He, Ar and maybe H 2 - Mobile phase in liquid chromatography is a liquid Requires analyte to be
More informationGAS CHROMATOGRAPHY. Mobile phase is a gas! Stationary phase could be anything but a gas
GAS CHROMATOGRAPHY Mobile phase is a gas! Stationary phase could be anything but a gas Gas Chromatography (GC) GC is currently one of the most popular methods for separating and analyzing compounds. This
More informationCh24. Gas Chromatography (GC)
Ch24. Gas Chromatography (GC) 24.1 What did they eat in the year 1000? From 13 C content of cholesterol in ancient bone 13 C : 1.1%, 12 C: 98.9% 13 C/ 12 C ratio types of plants Bones of 50 people in Barton-on-Humber
More informationChapter 31 Gas Chromatography. Carrier Gas System
Chapter 31 Gas Chromatography GAS-LIQUID CHROMATOGRAPHY In gas chromatography, the components of a vaporized sample are fractionated as a consequence of being partitioned between a mobile gaseous phase
More informationGas Chromatography. Rosa Yu, David Reckhow CEE772 Instrumental Methods in Environmental Analysis CEE 772 #16 2
Print version Gas Chromatography Rosa Yu, David Reckhow CEE772 Instrumental Methods in Environmental Analysis CEE 772 #16 1 Contents The primary components to a GC system 1. Carrier Gas System (including
More informationChromatographic Methods of Analysis Section: 5 Gas Chromatography (GC) Prof. Tarek A. Fayed
Chromatographic Methods of Analysis Section: 5 Gas Chromatography (GC) Prof. Tarek A. Fayed Gas Chromatography (GC) In gas chromatography, the sample is vaporized and injected onto the head of a chromatographic
More informationGC Instruments. GC Instruments - Sample Introduction
GC Instruments 1 Fairly simple instrumentation Maintaining constant average pressure is important! Pressure controls flow rate T influences retention (k ) Flow rate monitoring Changing flow rate changes
More information2401 Gas (liquid) Chromatography
2401 Gas (liquid) Chromatography Chromatography Scheme Gas chromatography - specifically gas-liquid chromatography - involves a sample being vaporized and injected onto the head of the chromatographic
More informationCHAPTER 6 GAS CHROMATOGRAPHY
CHAPTER 6 GAS CHROMATOGRAPHY Expected Outcomes Explain the principles of gas chromatography Able to state the function of each components of GC instrumentation Able to state the applications of GC 6.1
More informationGas Chromatography. Vaporization of sample Gas-solid Physical absorption Gas-liquid Liquid immobilized on inert solid
Gas Chromatography Vaporization of sample Gas-solid Physical absorption Gas-liquid Liquid immobilized on inert solid Principles Instrumentation Applications 18-1 Retention Volumes Volumes rather than times
More informationChromatography. Gas Chromatography
Chromatography Chromatography is essentially the separation of a mixture into its component parts for qualitative and quantitative analysis. The basis of separation is the partitioning of the analyte mixture
More information10/27/10. Chapter 27. Injector typically 50 C hotter than oven
Sample and solvent are vaporized onto the head of a column Vaporized solvent and solute are carried through the column by an inert gas (mobile phase) The mobile phase does not interact with compounds of
More information2. a) R N and L N so R L or L R 2.
1. Use the formulae on the Some Key Equations and Definitions for Chromatography sheet. a) 0.74 (remember that w b = 1.70 x w ½ ) b) 5 c) 0.893 (α always refers to two adjacent peaks) d) 1.0x10 3 e) 0.1
More informationGas Chromatography (GC)! Environmental Organic Chemistry CEE-PUBH Analysis Topic 5
Gas Chromatography (GC)! Environmental Organic Chemistry CEE-PUBH 5730-6730 Analysis Topic 5 Chromatography! Group of separation techniques based on partitioning (mobile phase/stationary phase). Two immiscible
More informationGas Chromatography. Presented By Mr. Venkateswarlu Mpharm KTPC
Gas Chromatography Gas Chromatography Presented By Mr. Venkateswarlu Mpharm KTPC What is Gas Chromatography? It is also known as Gas-Liquid Chromatography (GLC) GAS CHROMATOGRAPHY Separation of gaseous
More informationChromatographic Analysis
Chromatographic Analysis Distribution of Analytes between Phases An analyte is in equilibrium between the two phases [S 1 ] [S 2 ] (in phase 1) (in phase 2) AS [S2 ] K 2 A S [S1 ] 1 AS, A 1 S Activity
More informationPRINCIPLES AND APPLICATION OF CHROMATOGRAPHY. Dr. P. Jayachandra Reddy Mpharm PhD Principal & professor KTPC
PRINCIPLES AND APPLICATION OF CHROMATOGRAPHY Dr. P. Jayachandra Reddy Mpharm PhD Principal & professor KTPC CHROMATOGRAPHY Laboratory technique for the Separation of mixtures Chroma -"color" and graphein
More informationLuminescence transitions. Fluorescence spectroscopy
Luminescence transitions Fluorescence spectroscopy Advantages: High sensitivity (single molecule detection!) Measuring increment in signal against a dark (zero) background Emission is proportional to excitation
More informationAnalytical techniques: Environmental samples. Lecture 2 Universidade do Algarve
Analytical techniques: Environmental samples Lecture 2 Universidade do Algarve Terms, definitions & applications Difference between technique and method: Analytical technique: Fundamental scientific application
More informationIntroduction to Gas Chromatography
Introduction to Gas Chromatography 31-1 Objectives To know what is chromatography To understand the mechanism of compound separation To know the basic of gas chromatography system 31-2 Chromatography Definition
More informationGas Chromatography CHEM Dr. Reem M. Alghanmi st term
Gas Chromatography CHEM 313-5 Dr. Reem M. Alghanmi 2017 1 st term 17.7 Gas Chromatography Introduction There are two types of gas chromatography: Gas-solid (adsorption) chromatography. Gas-liquid (partition)
More informationChem 230, Fall, 2014 Homework Set # 3 Short Answer SOLUTIONS
Chem 230, Fall, 2014 Homework Set # 3 Short Answer SOLUTIONS 1. List two advantages of temperature programming in GC. a) Allows separation of solutes with widely varying retention factors in a reasonable
More informationGas Chromatography. Chromatography Laboratory Course. Dr. Christian Jungnickel Chromatography Course GC September 2005
Gas Chromatography Chromatography Laboratory Course The laboratory course experiments General Aim: Gain general experience using a GC Constant Injection technique Temperature variations Qualitative and
More informationCH 2252 Instrumental Methods of Analysis Unit V Gas Chromatography. M. Subramanian
CH 2252 Instrumental Methods of Analysis Unit V Gas Chromatography M. Subramanian Assistant Professor Department of Chemical Engineering Sri Sivasubramaniya Nadar College of Engineering Kalavakkam 603
More informationSkoog/Holler/Crouch Chapter 26 Principles of Instrumental Analysis, 6th ed. CHAPTER 26
Skoog/Holler/Crouch Chapter 26 Principles of Instrumental Analysis, 6th ed. Instructor s Manual CHAPTE 26 26-1. (a) Elution is a process in which species are washed through a chromatographic column by
More informationIntroduction to Capillary GC
?? Kβ? Page 1 Typical GC System Gas supply Injector Detector Data handling GAS Column Oven Page 2 CARRIER GAS Carries the solutes down the column Selection and velocity influences efficiency and retention
More informationVolatile organic compounds (VOCs):
Volatile organic compounds (VOCs): Organic chemicals with a high vapour pressure at room temperature. High vapour pressure results from a low boiling point. The World Health Organization (WHO) defined
More informationChromatographic Separation
What is? is the ability to separate molecules using partitioning characteristics of molecule to remain in a stationary phase versus a mobile phase. Once a molecule is separated from the mixture, it can
More information1. Carrier gas supply. - Flow rate measurement
Chapter 27 Gas chromatography Gas Chromatography - The components of a vaporized sample are separated as a consequence of being partitioned between a mobile gaseous phase and a liquid or a solid stationary
More informationChemistry Instrumental Analysis Lecture 27. Chem 4631
Chemistry 4631 Instrumental Analysis Lecture 27 Gas Chromatography Introduction GC covers all chromatographic methods in which the mobile phase is gas. It may involve either a solid stationary phase (GSC)
More informationChromatography Outline
Chem 2001 Summer 2004 Outline What is? The Chromatogram Optimization of Column Performance Why Do Bands Spread? Gas High-Performance Liquid Ion-Exchange 2 What is? In chromatography, separation is achieved
More informationDisadvantage: Destructive Technique once analyzed by GC, the sample is lost
Gas Chromatography Like other methods of chromatography, a partitioning of molecules must occur between the stationary phase and the mobile phases in order to achieve separation. This is the same equilibrium
More informationG a s C h r o m a t o g r a p h y Determination of Ethanol in Wine by Head-Space Gas Chromatography
G a s C h r o m a t o g r a p h y Determination of Ethanol in Wine by Head-Space Gas Chromatography Pibulsongkram Rajabhat University Department of Agro-Industry Faculty of Food and Agricultural Technology
More informationGas Chromatography (GC)
Gas Chromatography (GC) Ahmad Aqel Ifseisi Assistant Professor of Analytical Chemistry College of Science, Department of Chemistry King Saud University P.O. Box 2455 Riyadh 11541 Saudi Arabia Office: AA53
More informationCourse goals: Course goals: Lecture 1 A brief introduction to chromatography. AM Quality parameters and optimization in Chromatography
Emqal module: M0925 - Quality parameters and optimization in is a separation technique used for quantification of mixtures of analytes Svein.mjos@kj.uib.no Exercises and lectures can be found at www.chrombox.org/emq
More informationChapter 1. Chromatography. Abdul Muttaleb Jaber
Chapter 1 Chromatography Abdul Muttaleb Jaber What is Chromatography? Chromatography is a physico-chemical process that belongs to fractionation methods same as distillation, crystallization or fractionated
More informationBiochemistry. Biochemical Techniques. 12 Gas Liquid Chromatography
Description of Module Subject Name Paper Name 12 Module Name/Title 12 Gas - liquid Chromatography 1. Objectives 1.1 To understand principle of Gas Liquid Chromatography 1.2 To explain the different components
More informationCHEMISTRY Unit 3, Area of Study 1: Chemical Analysis
Watch this lesson online: https://edrolo.com.au/vce/subjects/chemistry/vce-chemistry/aos-1-chemical-analysis/chromatography-hplc-glc/column-chromatography/#watch CHEMISTRY Unit 3, Area of Study 1: Chemical
More informationExperiment 6 Simple and Fractional Distillation
Experiment 6 Simple and Fractional Distillation Vapor Pressure vs Temperature of Water Vapor Pressure vs Temperature of Water 25 Vapor Pressure vs Temperature of Water 25 Vapor Pressure (kpa) (kpa) 2 2
More informationChapter 11 Conventional Gas Chromatography
Chapter 11 Conventional Gas Chromatography Gas Chromatography GC is the first instrumental chromatographic method developed commercially It is relatively easy to introduce a stable flow and pressure for
More informationChapter 27: Gas Chromatography. Principles Instrumentation Detectors Columns and Stationary Phases Applications
Chapter 27: Gas Chromatography Principles Instrumentation Detectors Columns and Stationary Phases Applications GC-MS Schematic Interface less critical for capillary columns Several types of Mass Specs
More informationIntroduction to Capillary GC. Page 1. Agilent Restricted February 2, 2011
?? Kβ? Page 1 Typical GC System Gas supply Injector Detector Data handling GAS Column Oven Page 2 CARRIER GAS Carries the solutes down the column Selection and velocity influences efficiency and retention
More informationGC Instruments. GC Instruments - Columns
GC Instruments 1 Fairly simple instrumentation Maintaining constant average pressure is important! Pressure controls flow rate T influences retention (k ) Flow rate monitoring Changing flow rate changes
More informationLab 3 Guide: Gas Chromatography (GC) (Sept 8-14)
Lab 3 Guide: Gas Chromatography (GC) (Sept 8-14) How GC works The Basic Idea Gas chromatography (GC) is mainly used for the qualitative analysis of samples: it answers the question What chemicals are present
More informationChromatography and other Separation Methods
Chromatography and other Separation Methods Probably the most powerful class of modern analytical methods for analyzing mixture of components---and even for detecting a single component in a complex mixture!
More informationPrinciples of Instrumental Analysis
Principles of Instrumental Analysis Chapter 27 Gas Chromatography Gas Chromatography (GC): vaporized analytes (solutes) are partitioned between a mobile gaseous phase and a liquid or a solid stationary
More informationUnderstanding Gas Chromatography
Understanding Gas Chromatography What is Really Going on Inside the Box? Simon Jones GC Applications Engineer Page 1 Group/Presentation Title Month ##, 200X ?? K? Page 2 Typical GC System Gas supply Injector
More information2] The plate height in chromatography is best described as 2
9 Chromatography. General Topics 1] Explain the three major components of the van Deemter equation. Sketch a clearly labeled diagram describing each effect. What is the salient point of the van Deemter
More informationChem 321 Name Answer Key D. Miller
1. For a reversed-phase chromatography experiment, it is noted that the retention time of an analyte decreases as the percent of acetonitrile (CH 3 CN) increases in a CH 3 CN/H 2 O mobile phase. Explain
More informationHPLC. High Performance Liquid Chromatography (HPLC) Harris Chapter 25
High Performance Liquid Chromatography (HPLC) Harris Chapter 25 12/1/2005 Chem 253 - Chapter 25 1 HPLC Separation of nonvolatile or thermally unstable compounds. If the analyte/sample can be found to be
More informationHigh Pressure/Performance Liquid Chromatography (HPLC)
High Pressure/Performance Liquid Chromatography (HPLC) High Performance Liquid Chromatography (HPLC) is a form of column chromatography that pumps a sample mixture or analyte in a solvent (known as the
More informationLEARNING OBJECTIVES CHEM 212: SEPARATION SCIENCE CHROMATOGRAPHY UNIT. Thomas Wenzel, Bates College. In-class Problem Set Extraction.
LEARNING OBJECTIVES CHEM 212: SEPARATION SCIENCE CHROMATOGRAPHY UNIT Thomas Wenzel, Bates College In-class Problem Set Extraction Problem #1 1. Devise a scheme to be able to isolate organic acids, bases
More informationIntroduction to Chromatographic Separations
Introduction to Chromatographic Separations Analysis of complex samples usually involves previous separation prior to compound determination. Two main separation methods instrumentation are available:
More informationAnalytical Chemistry
Analytical Chemistry Chromatographic Separations KAM021 2016 Dr. A. Jesorka, 6112, aldo@chalmers.se Introduction to Chromatographic Separations Theory of Separations -Chromatography Terms Summary: Chromatography
More informationGas Chromatography. A schematic diagram of a gas chromatograph
Gas Chromatography In gas liquid chromatography (GLC) partition of solutes occurs between a mobile gas phase (the "carrier gas") and a stationary liquid phase present in the column. The gas-phase concentration
More informationCHEM 429 / 529 Chemical Separation Techniques
CHEM 429 / 529 Chemical Separation Techniques Robert E. Synovec, Professor Department of Chemistry University of Washington Lecture 1 Course Introduction Goal Chromatography and Related Techniques Obtain
More informationCHEM340 Tutorial 4: Chromatography
CHEM340 Tutorial 4: Chromatography 1. The data in the table below was obtained from a chromatogram obtained with a 10 cm liquid chromatography column. Under the conditions used, the compound uracil is
More informationPrinciples of Gas- Chromatography (GC)
Principles of Gas- Chromatography (GC) Mohammed N. Sabir January 2017 10-Jan-17 1 GC is a chromatographic technique utilizes gas as the mobile phase which is usually an inert gas (Hydrogen, Helium, Nitrogen
More informationHPLC Background Chem 250 F 2008 Page 1 of 24
HPLC Background Chem 250 F 2008 Page 1 of 24 Outline: General and descriptive aspects of chromatographic retention and separation: phenomenological k, efficiency, selectivity. Quantitative description
More informationPartitioning. Separation is based on the analyte s relative solubility between two liquid phases or a liquid and solid.
Chromatography Various techniques for the separation of complex mixtures that rely on the differential affinities of substances for a gas or liquid mobile medium and for a stationary adsorbing medium through
More informationCEE 772: Instrumental Methods in Environmental Analysis
Updated: 3 November 2014 Print version CEE 772: Instrumental Methods in Environmental Analysis Lecture #14 Chromatography: Theory (Skoog, Chapt. 26, pp.674-693) (Harris, Chapt. 23) (641-664) David Reckhow
More informationDATES: LAB: Liquid Chromatography Separation of Grape Kool-Aid
NAME: AP CHEMISTRY DATES: LAB: Liquid Chromatography Separation of Grape Kool-Aid PURPOSE There are a number of analytical techniques used to separate components of a mixture, or solution. They include
More informationChapter 26. An Introduction to Chromatographic Separations. Chromatography
Chapter 26 An Introduction to Chromatographic Separations Chromatography 1 Chromatography-Model as Extraction Chromatography-Model as Extraction 2 Chromatography Planar Chromatography-Types paper chromatography
More informationChapter content. Reference
Chapter 7 HPLC Instrumental Analysis Rezaul Karim Environmental Science and Technology Jessore University of Science and Technology Chapter content Liquid Chromatography (LC); Scope; Principles Instrumentation;
More informationLiquid storage: Holds the solvent which is going to act as the mobile phase. Pump: Pushes the solvent through to the column at high pressure.
High performance liquid chromatography (HPLC) is a much more sensitive and useful technique than paper and thin layer chromatography. The instrument used for HPLC is called a high performance liquid chromatograph.
More informationAbstract: An minimalist overview of chromatography for the person who would conduct chromatographic experiments, but not design experiments.
Chromatography Primer Abstract: An minimalist overview of chromatography for the person who would conduct chromatographic experiments, but not design experiments. At its heart, chromatography is a technique
More informationLiquid Chromatography
Liquid Chromatography 1. Introduction and Column Packing Material 2. Retention Mechanisms in Liquid Chromatography 3. Method Development 4. Column Preparation 5. General Instrumental aspects 6. Detectors
More informationIntroduction to Capillary GC
Introduction to Capillary GC LC Columns and Consumables Simon Jones Chromatography Applications Engineer February 20, 2008 Page 1 Introduction to Capillary GC t r K c?? Kβ k = - tr t m? t m R s Page 2
More informationChapter 26: An Introduction to Chromatographic Separations
Chapter 26: An Introduction to Chromatographic Separations Column Chromatography Migration Rates Distribution Contstants Retention Times Selectivity Factor Zone Broadening & Column Efficiency Optimizing
More informationThe Effects of Carrier Gas Viscosity and Diffusion on Column Efficiency in Capillary Gas Chromatography
Page 1 of 5 Return The Effects of Carrier Gas Viscosity and Diffusion on Column Efficiency in Capillary Gas Chromatography Stephanye D. Armstrong and Harold M. McNair Department of Chemistry, Virginia
More informationhttps://www.chemicool.com/definition/chromatography.html
CHROMATOGRAPHY 1 Chromatography - a physical method of mixture separation in which the components to be separated are distributed between two phases, one of which is stationary (stationary phase) while
More informationHigh Performance Liquid Chromatography
Updated: 3 November 2014 Print version High Performance Liquid Chromatography David Reckhow CEE 772 #18 1 HPLC System David Reckhow CEE 772 #18 2 Instrument Basics PUMP INJECTION POINT DETECTOR COLUMN
More informationHigh Performance Liquid Chromatography
Updated: 3 November 2014 Print version High Performance Liquid Chromatography David Reckhow CEE 772 #18 1 HPLC System David Reckhow CEE 772 #18 2 1 Instrument Basics PUMP INJECTION POINT DETECTOR COLUMN
More informationAUTOMATED ONLINE IDENTIFICATION AND MONITORING OF IMPURITIES IN GASES
JPACSM 127 AUTOMATED ONLINE IDENTIFICATION AND MONITORING OF IMPURITIES IN GASES Trace Analytical Inc. Menlo Park, CA ABSTRACT GC based gas analyzers with Reduction Gas Detector (RGD) and Flame Ionization
More informationInstrumentation. Components of a gas chromatograph
Gas chromatography Instrumentation Components of a gas chromatograph The components include the Mobile phase (Carrier gas) supply and pressure and flow rate regulators Injector the column the detector
More information1. Cyclic voltammetry involves the measurement of a diffusion controlled at an electrode in which the is controlled. (4 points)
Chem 454 First Exam Feb. 20, 2002 1. Cyclic voltammetry involves the measurement of a diffusion controlled at an electrode in which the is controlled. (4 points) 2. (5 points) A. Sketch a cyclic voltammogram
More informationColumn Liquid Chromatography Experiment Adapted for Use in Secondary Schools
Column Liquid Chromatography Experiment Adapted for Use in Secondary Schools Mark Langella WISTA The most modern and sophisticated methods of separating mixtures that the organic chemist has available
More informationGas chromatography. Flow measurement. Flow control. Injection methods. Flow measurement
Gas chromatography Schematic of a packed column gas chromatograph First instrumental chromatographic method developed commercially. Reason - it is relatively easy to produce a stable flow and pressure
More informationGas Chromatography. 1. Experiment Category: 2. Experiment Name: 3. Date and Issue number: 4. Instructor Name: 5. Institution: Ain Shams University
Project Title: e-laboratories for Gas chromatography 1. Experiment Category: Chemistry >> chromatography 2. Experiment Name: Gas Chromatography 3. Date and Issue number: 4. Instructor Name: 5. Institution:
More informationIntroduction to Chromatographic Separations (Chapter 1) Many determinations involve separation followed by analysis chromatography electrophoresis
Introduction to Chromatographic Separations (Chapter 1) Many determinations involve separation followed by analysis chromatography electrophoresis Chromatography: sample transported by mobile phase electrostatic
More informationCHROMATOGRAPHY. The term "chromatography" is derived from the original use of this method for separating yellow and green plant pigments.
CHROMATOGRAPHY The term "chromatography" is derived from the original use of this method for separating yellow and green plant pigments. THEORY OF CHROMATOGRAPHY: Separation of two sample components in
More informationIntroduction to Chromatography
Introduction to Chromatography Dr. Sana Mustafa Assistant Professor Department of Chemistry, Federal Urdu University of Arts, Science & Technology, Karachi. What is Chromatography? Derived from the Greek
More informationExam 3 Chem 454 April 25, 2018, Name
Exam 3 Chem 454 April 25, 2018, Name K = Cs/Cm k = (tr tm)/tm tr = tr tm = tr2 /tr1 = K2/K1 H = L/N = 2 /L Rs = tr/wavg R s t r, B r, A N t t r, B 4 70 total points. 14 questions @ 5 points each.s 1] Sketch
More informationCapillary GC Column Selection and Method Development A Primer on Column Parameters and Instrument Conditions
Capillary GC Column Selection and Method Development A Primer on Column Parameters and Instrument Conditions Michael D. Buchanan September 11, 2014 sigma-aldrich.com/analytical 2012 Sigma-Aldrich Co. All
More informationGas Chromatography notes
Gas Chromatography notes 1. Here is some terminology related to this experiment: Chromatography is a technique in which compounds to be separated are distributed between a mobile phase and a stationary
More informationInstrumental Chemical Analysis
L2 Page1 Instrumental Chemical Analysis Chromatography (General aspects of chromatography) Dr. Ahmad Najjar Philadelphia University Faculty of Pharmacy Department of Pharmaceutical Sciences 2 nd semester,
More informationFall 2012 Due In Class Friday, Oct. 19. Complete the following on separate paper. Show your work and clearly identify your answers.
CHEM 322 Name Fall 2012 Due In Class Friday, Oct. 19 Complete the following on separate paper. Show your work and clearly identify your answers. General Separations 1. Describe the relative contributions
More informationChromatographic Methods
10.537 Nanomaterial Characterization I Chromatographic Methods Prof. David Ryan Department of Chemistry UMass Lowell 1 Definitions Analytical Chemistry qualitative and quantitative measurement of chemical
More informationHPLC Workshop 16 June 2009 What does this do? Chromatography Theory Review Several chromatographic techniques Even though each method utilizes different techniques to separate compounds, the principles
More informationAtomization. In Flame Emission
FLAME SPECTROSCOPY The concentration of an element in a solution is determined by measuring the absorption, emission or fluorescence of electromagnetic by its monatomic particles in gaseous state in the
More informationExperiment 8: Chlorination of 1-Chlorobutane
1 Experiment 8: Chlorination of 1-Chlorobutane Alkanes contain only nonpolar carbon-hydrogen and carbon-carbon single bonds, which makes them unreactive toward most acidic and basic reagents. They can,
More informationChemistry Instrumental Analysis Lecture 34. Chem 4631
Chemistry 4631 Instrumental Analysis Lecture 34 From molecular to elemental analysis there are three major techniques used for elemental analysis: Optical spectrometry Mass spectrometry X-ray spectrometry
More informationAN INTRODUCTION TO ATOMIC SPECTROSCOPY
AN INTRODUCTION TO ATOMIC SPECTROSCOPY Atomic spectroscopy deals with the absorption, emission, or fluorescence by atom or elementary ions. Two regions of the spectrum yield atomic information- the UV-visible
More informationTheory and Instrumentation of GC. Chromatographic Parameters
Theory and Instrumentation of GC Chromatographic Parameters i Wherever you see this symbol, it is important to access the on-line course as there is interactive material that cannot be fully shown in this
More information/Chapter 27.ppt
Information given in these slides are, either in part or all, recollection from the followings: http://bionmr.unl.edu/courses/chem421-821/lectures/chapter-2... http://faculty.atu.edu/abhuiyan/course/chem
More informationChem 454 instrumental Analysis Exam 1 February 6 th, 2008
Chem 454 instrumental Analysis Exam 1 February 6 th, 2008 1 Name: 1] A glass electrode was immersed into a solution of ph 4.33 gave a response of 677.1 mv. This electrode was used to measure a sample solution
More informationIonization Techniques Part IV
Ionization Techniques Part IV CU- Boulder CHEM 5181 Mass Spectrometry & Chromatography Presented by Prof. Jose L. Jimenez High Vacuum MS Interpretation Lectures Sample Inlet Ion Source Mass Analyzer Detector
More informationChromatography and Functional Group Analysis
Chromatography Chromatography separates individual substances from a mixture. - to find out how many components there are - to match the components with known reference materials - to use additional analytical
More information