Gas Phase Chromatography - Kaiser, Rudolf

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Sommaire:
1. Theory of Capillary Chromatography.- The separation process in the capillary-The retention time as a characteristic value-Column performance of the capillary-The van Deemter-Golay equation-Optimum linear gas velocity and minimum HETP-Load capacity of the capillary-Summary of the factors which influence good column performance-Film thickness dF-Type and velocity of carrier gas.- Analytical task, time of analysis, and column performance required.- The required column performance-Determination of the number of theoretical plates-The required number of theoretical plates-Rapid analyses-The smallest possible length of capillary -Effect of temperature.- 2. Methods and Apparatus.- The carrier gas.- Type of gas-Gas purification.- Gas flow rate measurement and flowmeters.- Gas throughput measurements at the sample injector-High precision measurements.- The capillary.- Materials for capillaries-Production of long capillaries-Copper capillaries-Glass capillaries-Testing the capillary.- Flow of gas in a capillary.- Testing the capillary for cleanliness-Cleaning the capillary.- Coating the capillary.- The plug method-Film thickness and its control-The auxiliary solvent-Rate of coating-Adjustment of the gas flow rate needed for coating-Coating by the plug method using a microelectrolytic cell-Quantity of coating solution required-Evaporation and ageing of the solution film-The evaporation method-Concentration of coating solution and film thickness-Choice of solvent-Rate of coating-Coating temperature-Ageing of the capillary coating.- The sample injector.- Injection of gaseous substances-Injection of liquids-Injection of solids.- The splitter.- Summary on sample injection.- The detector.- The microflame ionization detector-Principle-Theory.- Amplifiers.- Measurement of amplifier sensitivity and linearity-Amplifier noise-Calculation of the amplifier sensitivity-Checking the sensitivity of the detector-Calculation of the factors for quantitative analysis.- Constructional details of the MFID.- Jet form Jet orifice-Insulated or earthed jet?-Collector electrode holder-Conductor cable, screening and earthing-Ionization voltage-Should the jet be negative or positive?-Ignition of the flame-Triode variant for a.c. operation of the MFID-Heating of the detector chamber-Production of optimum operating conditions-Base line stability-Conclusions -Stability of sensitivity.- ?-ray ionization detectors.- Principle-Sensitivity-Variants of the ?-ray ionization detector-Connection to the recorder-Constructional details-Sensitivity to disturbance.- 3. Applications.- Qualitative analysis.- Methods of identification-Direct chromatographic identification-Identification with selective preliminary separation-Preliminary chemical separation-Physical identifications-Identification by synthesis-Qualitative analysis with the aid of literature data.- Quantitative analysis.