Impure chemical mixtures can now be separated based on differences in molecular silhouette. Membranes have been developed with nanoscale pores that match the shape of impurities in the mix so that only the impurity can pass through. KAUST researchers have suggested that the first application of these metal-organic framework (MOF) based shape-selective membranes could be energy-efficient, low-cost purification of natural gas. 

MOFs are organic-inorganic hybrid crystalline porous materials that can feature different types of pores through their structure. By constructing MOFs from different organic and inorganic building blocks, researchers can finely tune the pore structure and aperture. MOF membranes have previously shown great potential for separating mixtures of molecules based on differences in their size or polarizability.

Read the whole story at KAUST Discovery