26th February 2020
Hydrogen gas has many uses in the lab. Often required as a carrier gas or a fuel gas in GC applications, hydrogen supplied by an on-site hydrogen generator is the safer and cost-effective alternative to pressurized cylinders. But which H2 generator should you opt for?
What to consider when buying a hydrogen generator for GC
When making the switch from pressurized cylinders to an on-site hydrogen generator, there are a couple of considerations to make which can help you buy the right hydrogen generator model for your lab and application. This depends on a number of factors, such as whether you’re using hydrogen as a carrier gas or a fuel gas and what type of flow rate you require.
In this blog, we’ll highlight the main points you will need to consider to make the right choice. If you’re looking to buy a hydrogen generator for carrier gas, you will first need to verify whether you can use hydrogen gas for your method. You can view our method list here to confirm. You can also use our free GC Calculator online for guidance on determining your GC requirements for your lab.
Thinking about your purity requirements for your application is a good starting point. If you’re going to use hydrogen as a carrier gas, it’s highly likely you will need a higher purity hydrogen generator. If, on the other hand, you require hydrogen as a fuel gas for applications such as FID, having the highest purity won’t normally be critical to your hydrogen requirements.
If you need hydrogen as a fuel gas, we would recommend Peak’s Precision Hydrogen and Precision Hydrogen SL models. These hydrogen generators are developed to offer a robust and reliable supply of hydrogen gas to detectors. The proton exchange membrane technology produces hydrogen from deionized water, which is then dried by desiccant filtration.
If you are going to use hydrogen as a carrier gas, our range of Precision Hydrogen Trace models would be your best option. While it can also be used for detectors requiring hydrogen as a fuel gas, Precision Hydrogen Trace is primarily designed for GC carrier gas use. Precision Hydrogen Trace produces hydrogen at 99.9999% purity by creating hydrogen from deoinized water utilizing its proton exchange membrane, which is then passed through a PSA dryer to remove moisture content.
Another factor to consider which will influence your choice of hydrgen generator if you require hydrogen for carrier gas is your flow requirement. To determine your flow rate, you will need to know your instrument’s total hydrogen demand at peak consumption. Once you’ve confirmed the maximum flow demand for each instrument, you can determine the total flow rate by adding these values together. For a rough guide of your flow rate requirements, multiply your total by 1.25 and 1.5 to get a buffer estimate of your flow rate. This means if your instruments’ total flow rate added up to 100mL/min, with estimates ranging between 125mL/min and 150mL/min, we would recommend a Precision Hydrogen generator with a maximum output of 200mL/min.
For pressure, you will find that for most GC instruments, up to 100psi delivery pressure is rarely critical. However, should your instrument be located far away from your generator, you will need to consider your pressure requirements in case there is a pressure drop through the tubing.
You might wonder whether hydrogen generators are difficult to maintain. Unlike cylinders or dewars, which need to be safety-checked regularly, hydrogen generators are hassle-free and require very little maintenance, all of which can be carried out in a lab. All you will need to do is refill the deionized water reservoir roughly once per week. Preventative maintenance is required annually for Precision H2, Precision SL and Precision Trace models, with swap out of the deioniser cartridge required to protect the PEM cell.
On-site hydrogen generators have paved the way for safer and cost-effective methods of supplying hydrogen gas. What is more, the popularity of hydrogen generators for GC applications has seen an increase with the recent helium shortage. Labs previously using helium for carrier gas are now opting for hydrogen supplied by a hydrogen generator as a more viable alternative. A hydrogen generator means labs can have a reliable source of hydrogen gas, eliminating risks of interrupted analyses. Labs can also produce their own gas, without relying on third parties for their gas supply, thereby reducing their overall costs.
When purchasing It’s essential for labs to know there are different types of hydrogen generators and that one generator might be more suited for their requirements than another. Should you require further information, get in touch today - Peak Scientific is here to help you with your selection.
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