Presentation on theme: "The world leader in serving science PLOT GC Columns and Applications Bonded TracePLOT Columns."— Presentation transcript:
The world leader in serving science PLOT GC Columns and Applications Bonded TracePLOT Columns
2 PLOT Columns - Introduction Porous Layer Open Tubular (PLOT) GC Columns are made by coating a layer of small particles on the inside wall of capillary tubing. Conventional capillary columns (WCOT, Wall Coated Open Tubular) are made by coating a layer of “liquid” phase on the inside wall of capillary tubing. PLOT columns are the best choice for analysis of highly volatile compounds such as permanent gases, solvents, and volatile petrochemicals such as refinery gases PLOT phases: Phases: TG-BOND Alumina (Na 2 SO 4 ) TG-BOND Alumina (KCl) TG-BOND Msieve 5A TG-BOND Q TG-BOND Q+ TG-BOND S TG-BOND U
4 PLOT – Column Stability “Modern” PLOT columns are engineered to provide stability and reproducibility: Reproducibility Using advances in technology PLOT column manufacturers are able to accurately control the process used to create the particles, enabling reproducible production of small particles with uniform diameter and pore size. Stability All of the particles are bonded to the tubing and/or to other particles, reducing particle generation. This reduces or eliminates detector spiking and changes in the flow characteristics through the column.
5 PLOT – Capillary Tubing Polyimide coating provides strength, flexibility and protection from stress corrosion caused by exposure to moisture Fused silica tubing Control of the Fused Silica dimensions is imperative to the performance of the GC column ID OD Shape Surface Activity
6 Solvent Mixture(TG-BOND Q) Argon in Air(TG-BOND Msieve 5A) Gas Standard (H 2,O 2,N 2,CH 4,CO)(TG-BOND Msieve 5A) Hydrocarbons C1-C4 (TG-BOND Alumina Na 2 SO 4 ) Hydrocarbons C1-C4(TG-BOND Alumina KCl) Application Focus: Refinery Gas Sample(TG-BOND Alumina Na 2 SO 4, Alumina KCl, Q+) PLOT – Applications
11 PLOT – C1-C4 Hydrocarbons Column:TracePLOT TG-BOND Alumina (KCl) 30m x 0.53mm x 10µm Part Number:26002-6080 Temperature:40ºC (1.0 minute hold) Ramp 1:To 200ºC at 10ºC/minute (10 minute hold) Detector Type:FID Carrier Gas:He Flow Rate:40.0 mL/min Injection Volume:100 µL Injection Mode:Splitless, 180°C 1.Methane 2.Ethane 3.Ethylene 4.Propane 5.Propylene 6.n-Butane 7.Acetylene 8.Propyne Note: Change in elution order for peaks 6 & 7
12 PLOT - Refinery Gas Analysis Porous Layer Open Tubular (PLOT) columns are well suited for the analysis of light hydrocarbons such as those found in refinery gases. These highly selective columns are capable of separating low molecular weight hydrocarbons at above ambient temperatures and the columns can then be programmed to higher temperatures to elute higher boiling compounds. The differences in selectivity of several types of PLOT columns is demonstrated by the differences in the separation of light hydrocarbons in a refinery gas sample.
13 PLOT - Refinery Gas Analysis-Alumina PLOT Alumina Columns Alumina is often used for the analysis of volatile hydrocarbons due to its selectivity which provides baseline resolution of most isomers at above ambient temperatures. The highly retentive nature of alumina requires that the surface be deactivated with inorganic salts such as sodium sulfate (Na2SO4) or potassium chloride (KCl) to control retention.
16 PLOT - Refinery Gas Analysis-Alumina Results PLOT Alumina Columns Not shown in these chromatograms, alumina Na2SO4 elutes methyl acetylene (a.k.a. propyne) after 1,3-butadiene, while alumina KCl elutes methyl acetylene before 1,3- butadiene. The selectivity and retention of alumina will be affected by water, which can come from impure carrier gas and from samples. Shorter retention times are evidence of exposure to water. If this occurs regenerate the column by conditioning for 30 minutes at 200°C under normal carrier gas flow. The upper temperature limit for TracePLOT Alumina columns is 200°C. Irreversible changes to the alumina adsorption properties will occur at higher temperatures.
17 PLOT - Refinery Gas Analysis-Porous Polymers Porous Polymer PLOT Columns Porous polymer PLOT columns can also be used for the analysis of the refinery gas sample. TracePLOT TG-BOND Q+ is a porous divinyl benzene homopolymer of intermediate polarity incorporating a lower amount 4-vinyl pyridine into the polymer. Note: Porous Polymer PLOT columns can tolerate water.