A quantitive microscale dynamic column breakthrough apparatus for measurement of unary and binary adsorption equilibrium on milligram quantities of adsorbent

A microscale dynamic column breakthrough (μDCB) apparatus with the ability to measure unary and binary adsorption equilibrium on a milligram-scale quantity of adsorbent is described. The μDCB is a low cost system that can be constructed through minor modifications of a commercial gas chromatograph and uses a thermal conductivity detector. The small scale of the apparatus allows for the rapid collection of dynamic column breakthrough experiments. The mass balances for adsorption and desorption experiments were derived along with a description of the blank. The μDCB apparatus was tested with 238.9 mg of zeolite 13X and 180.2 mg of activated carbon with single-component N2/He and CH4/He adsorption and desorption measurements. The measured equilibrium data agreed well with volumetrically collected data. These measurements are both accurate and precise. Multicomponent adsorption was also studied on zeolite 13X and activated carbon for CH4/N2 and CO2/CH4 mixtures. This data was compared with ideal and adsorbed solution theory, extended dual-site Langmuir calculations and the literature.

A Review on the Challenges of Using Zeolite 13X as Heat Storage Systems for the Residential Sector

In recent years, several attempts have been made to promote renewable energy in the residential sector to help reducing its CO2 emissions. Among existing approaches utilizing substances capable of directly storing and transporting thermal energy has recently become a point of interest. Zeolite 13X with exceptional capacity to safely store thermal energy for long periods and release heat due to its unique molecular structure is known to be one of the best options serving this purpose. However, the application of this ceramic as a heat storage material in the residential sector is associated with significant challenges dictated by the limitations of the sector, such as space restrictions and affordability. The current review attempts to explore the extent of these challenges, mainly related to design and efficiency from different perspectives. The main aim here is to provide a clear vision for a better understanding of the state of the art of this technology and to help to identify possible solutions fostering the adaptation of this technology to the residential sector.

Diversifying databases of metal organic frameworks for high-throughput computational screening

By combining metal nodes and organic linkers, an infinite number of metal organic frameworks (MOFs) can be designed in silico. When making new databases of such hypothetical MOFs, we need to assure that they not only contribute towards the growth of the count of structures but also add different chemistry to existing databases. In this study, we designed a database of ~20,000 hypothetical MOFs which are diverse in terms of their chemical design space—metal nodes, organic linkers, functional groups and pore geometries. Using Machine Learning techniques, we visualized and quantified the diversity of these structures. We find that on adding the structures of our database, the overall diversity metrics of hypothetical databases improve, especially in terms of the chemistry of metal nodes. We then assessed the usefulness of diverse structures by evaluating their performance, using grand-canonical Monte Carlo simulations, in two important environmental applications—post combustion carbon capture and hydrogen storage. We find that many of these structures perform better than widely used benchmark materials such as Zeolite-13X (for post combustion carbon capture) and MOF-5 (for hydrogen storage).