Simultaneous capture of trace benzene and SO2 in a robust Ni(II)-pyrazolate framework

Abstract

Benzene and SO2, coexisting as hazardous air pollutants in some cases, such as in coke oven emissions, have led to detrimental health and environmental effects. Physisorbents offer promise in capturing benzene and SO2, while their performance compromises at low concentration. Particularly, the simultaneous capture of trace benzene and SO2 under humid conditions is attractive but challenging. Here, we address this issue by constructing a robust pyrazolate metal-organic framework (MOF) sorbent featuring rich accessible Ni(II) sites with low affinity to water and good stability. This material achieves a high benzene uptake of 5.08 mmol g–1 at 10 Pa, surpassing previous benchmarks. More importantly, it exhibits an adsorption capacity of ~0.51 mmol g–1 for 10 ppm benzene and ~1.21 mmol g–1 for 250 ppm SO2 under 30% relative humidity. This work demonstrates that a pioneering MOF enables simultaneous capture of trace benzene and SO2, highlighting the potential of physisorbents for industrial effluent remediation, even in the presence of moisture.