Professor Suk Bong Hong (School of Environmental Science and Engineering) and his research group have discovered that PST-1 (POSTECH number 1), the newly named synthetic small-pore zeolite molecular structure, selectively adsorbs hydrogen.

The zeolites’ ability to discriminate between molecules of different sizes and shapes has long been recognized. However, examples of selective adsorption of the smallest gases in zeolites are scarce.

PST-1, the synthetic small-pore zeolite with the natrolite topology and a potassium gallosilicate composition, was discovered to adsorb only the smallest gases, thus allowing discrimination from slightly larger molecules, and furthermore, to be selective for hydrogen over helium, despite the smaller size of the latter.

The research has been watched closely, because PST-1, which dehydrates easily at low temperature (60°C) and stably maintains its structure at high temperature (800°C), suggests the possibility of its utilization as the first selective separation material for the small gas molecules such as hydrogen and helium. The PST-1 zeolite is also expected to be used in effective discrimination of carbon dioxide, the primary greenhouse gas.

The pre-existing method used for hydrogen separation requires a temperature above 300°C, or removes impurities rather than adsorb hydrogen, so the synthesis of PST-1 is expected to propel development of more economical and selective manufacturing process for high purity hydrogen, explained Professor Hong.

An international patent application process is ongoing for the technology, with the anticipation that the high purity hydrogen production and carbon dioxide dissociation using the unique discriminative quality of PST-1 is to become pivotal technology in the environmental and energy industries.

The research results were introduced in Angewandte Chemie Volume 48, Issue 36.

Professor Suk Bong Hong
School of Environmental Science and Engineering
Tel: +82-54-279-2284
Fax: +82-54-279-8299
E-mail: sbhong@postech.ac.kr