Air Products licenses NTNU CCS membrane tech

AIR PRODUCTS has exclusively licensed CO₂ membrane capture technology developed by chemical engineers at the Norwegian University of Science and Technology (NTNU).

The proprietary fixed site carrier membrane was developed by NTNU chemical engineering professor May-Britt Hägg and her team. It will be used by Air Products as part of its PRISM gas separation membrane technology offerings, which are already used by industries around the world to separate gases such as nitrogen, hydrogen and methane with high purity.

Most CCS plants use amine solvents to capture CO₂ but attention is increasingly turning to membranes as the solvents require a relatively expensive regeneration step. Hägg explained to The Chemical Engineer the membrane technology is “also a modular technology so it is easy to adapt to large or small gas streams. Last but not least, it is less energy demanding and has a smaller footprint, which usually means it will be cheaper than other capture technologies.”

The membrane developed by Hägg and her team is based on a composite membrane of hollow fibres, spun from polysulfone, supplied by Air Products in its proprietary PRISM casing. Hägg’s team has developed a thin selective coating for the membrane, made from polyvinylamine, which separates the CO₂. It contains fixed amine groups on the polymer backbone which, says Hägg, function as the carrier for the CO₂ through the membrane when humidity is present in the gas stream.

“The preparation of this coating and various other aspects concerning the application of the coating was patented by NTNU. Air Products has now licensed these patents, and will in the future do all the steps of the preparation of the modules themselves, as well as further scaling up,” Hägg told The Chemical Engineer.

Air Products expects the new technology to be particularly useful for coal-fired power plants and in the cement industry, and says that it will take CO₂ capture to “a new level of efficiency”.

Charles Page, director of Air Products' PRISM Membranes division, added: “Air Products is committed to developing solutions that enable our customers to minimise the impact of their operations on the environment. We are confident that our licence agreement with NTNU will provide Air Products with the technology to manufacture gas membrane separators that are revolutionary in CO₂ capture.”

It is not yet clear when the new membranes will be commercially available.