Click here to learn more about the New CDS Pyrolysis Sample Prep Station where you can prepare and store everything you need to prepare samples all in one unit.
Q- What types of samples can be analyzed with a pyrolyzer?
A- The pyrolysis technique can be used to introduce any volatile and non-volatile organic into a GC, GC/MS or other analytical instruments including FTIR and direct MS. By using a programmed temperature approach, you can selectively analyze polymers, semi-volatile additives and other volatile compounds such as residual monomers, solvents, contaminants etc.
Q- What is the heating rate of the Pyroprobes?
A- All CDS Pyroprobes have adjustable heating rates from a slow .01°C/minute to as fast as 20,000°C/second. You have complete flexibility between these rates for each method you program into the system.
Q- When the sample is removed from the pyrolyzer, will air get into the system?
A- No. All CDS Pyroprobes continually purge the system upon sample removal to prevent this. Either the carrier gas or a separate purge gas (normally He or N2) can be used for this purpose.
Q- What are the differences between resistively heated, Curie Point and furnace technologies?
A- Resistively heated systems use a metal filament to control the pyrolysis temperature. The CDS Pyroprobes use a pure Platinum (Pt) filament which gives it a maximum temperature range of 1400°C. Since the filament is being heated and monitored by the Pyroprobe electronics, the temperature, heat rate and pyrolysis time can be continuously controlled for the widest range of analytical parameters when compared to Curie Point and Furnace technologies.
Curie Point systems use a ferromagnetic sample holder and the sample is then heated by an electromagnetic inductor. Curie point systems cannot control the heat rate (only fast-pulsed pyrolysis) and they have limited programming capabilities within the published temperature range since the actual ferromagnetic sample holder determines the end point temperature.
Furnace pyrolyzers use a micro furnace that is heated to a fixed temperature and the sample is dropped in and pyrolyzed. They have some ability to program the heat rate, but since the furnace heats very slowly, there are limitations in heat rate. Additional cooling gases are needed to cool the system down between runs.
All three technologies offer very similar maximum temperatures, but the flexibility of the resistively heated technology is what really differentiates it from the others.
Q- Can the Pyroprobes perform Evolved Gas Analysis (EGA?)
A- Since all CDS Pyroprobes have programmable heating rates, we can perform EGA directly to the MS or pyrolyze to an analytical (built-in) trap. When operating in this mode, the resultant pyrogram is similar to the results seen from a TGA- MS system, except the pyrolysis system can only determine weight before and after the analysis, if the user chooses to do this.
Q- What is the precision of the programmed temperature?
A- +/- 1°C of the actual set point
Q- What is the published system accuracy?
A- CDS pyrolyzers guarantee the best system accuracy for any laboratory pyrolyzer. Published specifications are < 2% RSD when comparing trimer/monomer ratios of polystyrene samples.
Q- What are the differences between models?
A- Please see the our chart. We have basic single step pyrolyzers to more advanced systems with trapping capabilities, built-in reactors, autosamplers and high-pressure capabilities.
Q- Can you do quantitation with pyrolysis?
A- The pyrolysis technique is very reproducible (see system accuracy specifications) and can be used for quantitation of polymers and additives. As with any form of quantitation, a complete set of analytical standards must be analyzed for any given matrix.
Q- How is the system mounted?
A- CDS recommends the use of a heated transfer line which connects the pyrolyzer to the GC injection port. However, CDS offers both injection port mounted systems and easy install/removal heated sample line versions. All CDS systems will keep the sample at or above the injection port temperature until it enters the injection port.
See chart for model description.
Q- How is the carrier gas of the GC controlled during pyrolysis?
A- The sample is delivered to the GC in GC carrier gas, and the pressure, flow and split ratio are controlled by the GC as with any other application.
Q- How hard is it to remove and reinstall the Pyroprobe?
A- Once installed, the Pyroprobe may be removed by disconnecting the interface or transfer line from the injection port and turning the GC carrier back to the injector, which takes 5 to 10 minutes.
Q- What are the materials of the sample pathway?
A- Our system uses a platinum heating element for accurate programmed heating of the sample. The entire sample pathway uses an inert material, silco-steel, to prevent any secondary reactions.
Q- How do you load the samples?
A- Samples are loaded into quartz tubes or open “boats” and inserted into a coil probe. For liquid samples or meltable solids, you can use the ribbon probe and place them directly on a flat platinum ribbon probe. You can easily change from one probe style to the other.
Q- Are there any maintenance requirements?
A- When used properly, there is very little maintenance required with the manual systems. On average, you may change the filament a few times per year. For the autosampler, valve rotors will need to be changed depending on your sample load. It is an easy process that most users do themselves.
Q- What is the recommended sample size?
A- For most samples, such as paints, rubbers and plastics, you only need to use 50-200 micrograms (µg). Larger sample sizes may overload your GC column or cause some carry over. For samples with trace organics in a non-organic matrix (geological samples), we have larger probe sizes that will facilitate samples over 300 milligrams (mg). It is important to discuss this with your authorized CDS representative or the factory to understand what system is needed.
Q- Can you pyrolyse in any gas other than helium?
A- We offer several trapping pyrolyzers (model 5200, 5250T, 5200HPPR) where you can pyrolyse in any reactant gas (typically Oxygen, Hydrogen, Methane, and Air are used), the products of pyrolysis are trapped on an analytical trap while the reactant gas is vented so that it does not get to the GCMS. Helium, Nitrogen or Hydrogen are typically used as the GC carrier gas, and pyrolysis can be performed in any of these carrier gases as well as the reactant gas. This can easily be controlled by the pyroprobe software.
Q- Do you offer any libraries to help interpret data?
A- Yes, we have a polymer library to help identify polymers (containing over 400) and an additive library. The additive library searches a pyrogram for specific additives or the individual pyrolysis products of additives, directly or using Deconvolution software. Libraries come in several different formats including Chemstation and AMDIS. The additives are broken down into different categories to help aid in the search you are interested in. Both libraries must be used in conjunction with a GCMS system only. Learn more.
Q- Can you upgrade the instruments?
A- All 5000 series CDS pyrolyzers are upgradeable to other models, including to the autosampler. Some are field upgradeable and others may have to come back to the factory. Please contact CDS for further details on upgrades.
Q- What detector is needed?
A- Although most users are using a GCMS, some are still using FID detectors for more routine analysis and QC applications.
Q- Can a liquid sample be analyzed?
A- You can inject liquid samples into the sample tubes/boats or onto the Pt ribbon probe for analysis. Some of the CDS injection port mounted interfaces also have injection ports for a direct syringe injection to the GC.
Q- Are the sample tubes and boats reusable.
A- Yes, but cleaning may be necessary between use. A cleaning function is built into all CDS pyroprobes.
Q- Is software included?
A- All systems come with operating software. Libraries are available for an additional cost.
Q- How do I run the operating software?
A- The software runs on the same computer controlling the GC.
Q- What model GC can we install the pyrolyzer on?
A- CDS can connect with any make or model GC. We will ask you to supply this information upon ordering.
Q- How do I start the GC after pyrolyzing?
A- The pyrolyzer is integrated to the GC through the remote start cable we supply. We supply the appropriate cable for the GC you decide to install the pyrolyzer on. By starting the pyrolyzer, we look for a GC ready signal and when the GC is ready to accept a sample pyrolysis will begin. When the sample is sent to the GC, the GC will automatically be started.
Q- Can glass wool be used to load the sample tubes in place of the quartz wool supplied by CDS?
A- No. Glass wool can’Äôt be used as a substitute for quartz wool as it will melt at the high temperatures used for pyrolysis.