As labs continue to face shortages and escalating prices of helium gas, many scientists are seeking an alternative solution. With scientists using gas in many ways—including sample preparation and various forms of chromatography—labs need a reliable and affordable supply. Instead of buying tanks of helium, a lab can turn to a hydrogen generator.
To help scientists make the transition from helium to hydrogen gas, product manager Ed Connor of Peak Scientific in Scotland compiled a seven-step plan. In summary, here’s how to make the switch:
1. Confirm that hydrogen can be used in your methods. In some situations, method-translation software can be used to determine the parameters that might need adjustment.
2. Replace the tubing that was used for helium gas to eliminate unwanted background from deposits.
3. Select a hydrogen generator that meets safety concerns of this explosive gas and includes a leak detector that provides automatic shutoff if needed.
4. Install any needed hardware, which for gas chromatography (GC), for example, may include a more efficient vacuum pump or hydrogen upgrade kit for the ion source.
5. Change consumables as needed. In some applications of GC, for instance, the switch to hydrogen may require a smaller-bore column.
6. Set up the system, which will vary based on the platform and application. With GC, for example, the column must be conditioned in a GC oven and the ion source must be baked out according to manufacturer guidelines.
7. Check the performance. As Connor notes, “Signal to noise is often reduced—two to five times depending on the system—when comparing results of samples run with helium compared with hydrogen.” He says: “A few days following changing carrier gas, the background signal should drop to a consistent level.”
Once the decision is made to switch to hydrogen gas, a lab sets up the generator, and this process varies by manufacturer. Some hydrogen gas generators are “very simple in design,” says James Layton, chief technologist at FuelCellsEtc in College Station, TX. According to Layton, “With proton exchange membrane (PEM) hydrogen generators, you simply need to add deionized or distilled water and plug the generator into the wall.” He adds, “There are some types of generators—alkaline—that require a potassium-hydroxide mixture to be added to the reactant tank first, then topping off with deionized or distilled water as needed.”
A hydrogen gas generator can also monitor the production process. As an example, Layton says, “If the hydrogen is filling a large tank or being used in real time, then the unit would continue to operate, producing maximum flow of hydrogen until the pressure reaches its maximum or the generator is turned off.”
In general, the switch from helium to hydrogen is straightforward. If a method can use hydrogen, making the switch to a hydrogen generator is fairly easy. In many cases, a hydrogen generator can be “plug and play.”