Gas chromatography experiment

Details for producing optimum performing packed, capillary, and fiberfilled columns in inverse gas chromatography experiments are discussed. Also, the crucial factors that might lead to instrumental error in this technique are evaluated and cautions are provided. 

Figure 1. Experimental apparatus for inverse gas chromatography experiment.

Figure 4. Comparison of Inverse gas chromatography experiments on Illinois No. 6 coal.

Figure 10. Comparison of inverse gas chromatography experiments on the Upper Freeport coals that have undergone various oxidative treatments.

Your instructor will select one experiment for teams to perform validation studies. An example is a gas chromatography experiment such as Experiment 32, but for one analyte. A flow injection analysis (FIA) experiment, such as Experiment 37, would be a good choice as well, since multiple measurements can be made rapidly. The team will determine linearity, accuracy, precision, sensitivity, range, limit of detection, limit of quantitation, and robustness (repeatability) of the method. In addition, a control chart will be prepared over at least one laboratory period. The instructor will have available a reference standard to use for accuracy studies. Plan for two laboratory periods for the completed study. A report of the method will be prepared and documented. Before beginning the experiment, you should review method validation in Chapter 4. 

Fig. 3.9 Structure of A[Cu3((jl3-OH)( X3—4-carboxypyrazolato)3] (A = NH or Et3NH+) and the results of variable-temperature pulse gas chromatography experiments based on an equimo-lecular C2H2/N2/CH4/CO2 gas mixture passing through a chromatographic column packed with this material. Reprinted from Ref. [57] Copyright 2011, with permission from Elsevier...

A careful discussion of the results of online isothermal gas chromatography experiments with the group-4 elements Zr, Hf, and Rf, is given by Turler (1996). The most recent results are given by Kadkhodayan et al. (1996). In these experiments, a M0O3 aerosol gas jet was used to transport the activities from the recoil chamber to the chromatography apparatus. 

Gas chromatography experiments (injection port 150°, column 60°) on the chelates in hfaa solutions gave two distinct peaks, the first presumably due to the solvent, and the second that of the chelate. However, the retention times of the individual chelates (with the columns so far used) did not differ sufficiently to make quantitative determinations possible. No third peak which might be attributed to acetone from the addition product was observed. 

Due to the presence of some methylene chloride in the sample of the chiral amine, you may obtain low rotation values from polarimetry. Because of this, your calculated value of the optical purity (enantiomeric excess) and percentages of the enantiomers will be in error. The percentages of the enantiomers obtained from the optional chiral gas chromatography experiment below should provide more accurate percentages of each of the stereoisomers. 

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