CO2 Separation Membrane Developed for Industrial Exhaust Gas ~ Confirmed Approximately Five Times the Separation Factor of DDR-Type Zeolite Membrane

NGK INSULATORS, LTD. (“NGK”) has developed a carbon dioxide (CO₂) separation membrane for industrial exhaust gas. In testing with simulated industrial exhaust gas, the membrane achieved CO₂ separation factor approximately five times that of conventionally developed DDR-type zeolite membrane used for CO₂ separation. The Company aims to continue with development for further increases in separation performance, aiming for commercialization in 2030 after demonstration testing.

The Company has been successful in developing a DDR-type zeolite membrane, which is one of the world’s largest ceramic CO₂ separation membranes. Demonstration testing of these membranes is currently in progress with a view to using them for separating CO₂ from associated gas and natural gas. Amid a global shift towards carbon neutrality, there is a growing social need for CO₂ separation and recovery technology for industrial exhaust gas emitted from plants and so forth. NGK has therefore used its large membrane manufacturing technologies and technologies for forming uniformly membranes to develop a new CO₂ separation membrane for industrial exhaust gas.

The conventionally developed DDR-type zeolite membrane can be used for CO₂separation using differences in molecule size. It is easily able to separate CO₂in associated gas and natural gas, since methane, their major component, has a larger molecule size than CO₂. On the other hand, in industrial exhaust gas, the major components are nitrogen and oxygen, which have molecule sizes similar to CO₂. Therefore, it is difficult to precisely separate CO₂ from industrial exhaust gas using a DDR-type zeolite membrane. The newly developed CO₂ separation membrane for industrial exhaust gas makes use a difference in adsorption characteristics (affinity) for molecules to separate CO₂ from nitrogen and oxygen, which increases CO₂ separation factor. In testing uses simulated industrial exhaust gas, the new membrane was confirmed to have approximately five times the CO₂separation factor of a conventionally developed DDR-type zeolite membrane. Using the characteristics of ceramics, which can be used under harsh conditions, the Company is working to increase the separation factor even further for high temperature industrial exhaust gases, aiming for commercialization in 2030 after demonstration testing.

In April 2021, the NGK Group formulated the NGK Group Environmental Vision. The vision calls for 50% reduction in CO₂ emissions compared with fiscal 2013 by fiscal 2030 and aims to achieve net zero emissions by fiscal 2050. Through the development and provision of various membrane technologies going forward, NGK will work to reduce CO₂ emissions through the spread of technologies for the separation, recovery, and effective use of CO₂, and contribute to the realization of carbon neutrality.

Subnano-ceramic membrane

Subnano-ceramic membrane separation system

Comparison of separation factor of CO₂ and nitrogen (N₂)