In situ NPD studies of Porous Metal-Organic Frameworks for Selective Benzene Capture

Benzene is one of the most important volatile organic compounds (VOCs) as well as a major indoor air pollutant posing a serious threat to public health due to its carcinogenicity. Furthermore, the separation of benzene and cyclohexane is vital for the production of high-purity cyclohexane in chemical industry. The removal of trace amount of benzene from air or benzene/cyclohexane mixture demands materials with outstanding affinity and capture efficiency. Metal-organic frameworks (MOFs) have shown great potential for toxic gas adsorption and separation. We seek to develop new sorbent materials for the efficient capture of benzene and request 4 days on WISH to study the adsorption behaviour of benzene and cyclohexane molecules in two robust MOF materials (MFM-125 and MFM-125-defect). Introduction of structural defects in MFM-125 has led to exceptionally high adsorption capacity for benzene at low-pressure region and high selectivity for benzene/cyclohexane separation in MFM-125-defect, suggesting the presence of specific host-guest interactions. The understanding of the intermolecular interactions between the porous framework and the hydrocarbon guests will tremendously benefit from the high resolution and the high sensitivity to light elements of neutron powder diffraction at WISH.