11 June 2021

Contributors invited for study on measuring H20 sorption isotherms

International standardisation network VAMAS Is calling for participants to perform interlaboratory comparison of water/BAM-P109 (activated porous carbon) adsorption isotherms and to recommend best practices for vapour sorption measurements.


Carbon vapour instrument

Water vapour sorption measurement on BAM-P109 in a gravimetric instrument

© Giang Huong Nguyen

Adsorbents are candidate materials for many commercial and industrial applications, including carbon capture, catalysis, environmental remediation, natural gas purification, hydrogen and natural gas fuel storage. 

Although new and improved adsorbents continue to emerge for the various applications, the pace of innovation is hindered by the lack of robust methods to characterise gas sorption behaviour of materials.

There are currently no standards for water adsorption isotherm data. The ISO TC24/SC4 committee has published standards for surface area determination as well as pore size/pore volume characterisation of an adsorbent by physical adsorption. The standards are of high relevance for solid sorbents. Work done under the current study will complement ISO TC24/SC4 standardisation efforts on solid sorbent materials and feed into new water sorption standardisation work. 

The study will measure uptake of water vapour on BAM-P109 at 25°C using a vapour sorption instrument. Water was chosen for the general interest in water sorption on porous materials, which can provide insights into the hydrophilicity, pore structures and chemical stability of a material. The adsorbent will be provided for the study along with a study protocol. Water sorption isotherms may take up to one week or longer to complete.

The resulting methods and data will be made available at the NIST adsorption website and published in a peer ­reviewed journal. The study will feed into ISO water sorption standardisation work. 

Participants will be required to fund their own involvement in the project. Expressions of interest must be made by 17 July 2021 to [email protected]