Australia project showcases hydrogen–helium separation tech

German firm Siqens has proved its hydrogen separation technology at CSIRO’s Hydrogen Technology Demonstration Facility (HTDF) in Victoria, Australia.

The findings could support efforts to separate helium and naturally occurring hydrogen, also known as geological or white hydrogen.

Both gases are often found together and need to be separated using specialist technology for hydrogen to be used as a fuel. For this project, Siqens used CSIRO’s test facility to demonstrate its electrochemical hydrogen separation rig.

The team mimicked the separation of a naturally occurring concentration by feeding hydrogen–helium mixtures ranging from 10% to 75% into the rig.

“We showed that the rig can produce up to 4.7kg of fuel cell quality hydrogen per day, which is much higher … than had previously been demonstrated,” said Matthew Purcell, Project Manager for Siqens.

The electrochemical process works using a special membrane that allows hydrogen atoms to pass through the system. Unlike the size-based ‘sieving’ used in air separation units, the membrane is selective for protons.

To pass through the membrane, a molecule must be able to split into protons – specifically hydrogen ions – and those protons travel through the membrane and recombine into hydrogen on the other side. At the same time, helium, being inert, cannot be broken down and remains on the other side.

By the end of the separation process, the helium is left behind on one side and the recombined purified hydrogen is collected on the other.

The demo project also gave Siqens the opportunity to showcase its separation technology to potential partners. According to Purcell, 25 different organisations came to see the rig in action.

The lure of Australia

The German company chose CSIRO’s facility because of Australia’s ample reserves of naturally occurring hydrogen.

“We wanted to demonstrate our hydrogen separation technology in Australia because of the country’s natural hydrogen industry,” said Purcell.

Interest in the sector has surged, with South Australia seeing a rush of exploration activity. In a twelve-month period between 2021 and 2022, six different companies were either granted or had applied for 18 petroleum exploration licences across the state, according to Australian energy consultancy EnergyQuest.

The area under permit is equivalent to around 32% of the entire state, an approximate 570,000 square kilometres.

The naturally occurring energy source is attractive to many companies because of its potential to be three to four times cheaper than producing it via electrolysis or gas reforming with carbon capture.

Energy firm Gold Hydrogen has previously described natural hydrogen as an “inexhaustible source of green energy” and estimates natural hydrogen could be produced for less than $2.30 per kg, compared to over $6 per kg for hydrogen made via electrolysis or reforming.

However, it is not clear if these costs factor in the well drilling process that is necessary to access concentrations that remain unproven.

The strength of the sector was outlined in the Australian government’s National Hydrogen Strategy, which is supported by Geoscience Australia’s digital mapping capabilities.

Currently, South Australia is the only Australian jurisdiction with laws in place to enable hydrogen exploration. However, the 2024 strategy encourages further research and exploration, even though large-scale development strategies are not yet in place.