What is column in gas chromatography?
The column is the heart of the gas chromatograph. It is through interactions between solutes (individual compounds in the sample, also called analytes) and the stationary phase within the column that separation can occur.
How does Column length affect gas chromatography?
A longer column generally improves the separation. The trade-off is that the retention time increases proportionally to the column length and a significant peak broadening will be observed as well because of increased longitudinal diffusion inside the column.
What is the stationary phase of GC column?
A stationary phase is the film chemically bonded to or coated on the inner wall of a capillary column, and should be selected based on the application to be performed.
What is the length of GC column?
4. Column Length
| Column Length (m) | Inlet Pressure (psi) | Peak 1 Retention (min) |
|---|---|---|
| 15 | 5.9 | 8.33 |
| 30 | 12.0 | 16.68 |
| 60 | 24.9 | 33.37 |
| Note: Theoretical values for 0.25 mm I.D. columns with 85% coating efficiency, 145 Â °C isothermal analyses, helium at 21 cm/sec, k (peak 1) = 6.00 |
How many columns are in GC?
Thus, the total plates available in long capillary columns range from 180 000 to 300 000, whereas packed columns typically generate only 4000 plates and have much lower resolution….Figure 5.
| Column length | Resolution | Speed |
|---|---|---|
| Medium (25–30 m) | Good compromise between resolution and speed | |
| Short (5–10 m) | Moderate | Fast |
How many columns are used in gas chromatography?
Two types
Two types of columns are used in gas chromatography: packed columns and capillary columns.
What makes a restek RXi column so good?
In addition to outstanding performance, this combination of column characteristics assures Rxi columns will have long lifetimes. Restek chemists have also developed a stable, reproducible manufacturing process so that Rxi columns will meet your needs every time you install a new column.
Why are RXi columns used in high GC ovens?
Rxi columns are manufactured for low column bleed—even at high GC oven temperatures—to shorten post-installation conditioning time and get your instrument up and running faster. All of these characteristics help minimize the need for maintenance, reduce your downtime, and raise the productivity of your instrument.
What makes RXi capillary GC columns the best?
Rxi fused silica capillary GC columns were designed specifically to be the best columns available for exceptional inertness, ultra-low bleed, and reproducible retention and selectivity. In addition to outstanding performance, this combination of column characteristics assures Rxi columns will have long lifetimes.
Why do you need a stationary phase in RXi GC?
Choosing the right stationary phase can make all the difference for the success of your analysis. We have developed a wide selection of stationary phases that span the polarity range, so you can easily select a perfectly matched Rxi GC column that helps you run faster and produce unbeatable results.