Insights into the Adsorption of VOCs on a Cobalt-Adeninate Metal-Organic Framework (Bio-MOF-11)

Ruofei Chen; Zhengxin Yao; Ning Han; Xiancheng Ma; Liqing Li; Shaomin Liu; Hongqi Sun; Shaobin Wang

doi:10.1021/acsomega.0c01504

Insights into the Adsorption of VOCs on a Cobalt-Adeninate Metal-Organic Framework (Bio-MOF-11)

ACS Omega. 2020 Jun 15;5(25):15402-15408. doi: 10.1021/acsomega.0c01504. eCollection 2020 Jun 30.

Authors

Ruofei Chen^{1

2}, Zhengxin Yao², Ning Han², Xiancheng Ma¹, Liqing Li¹, Shaomin Liu², Hongqi Sun³, Shaobin Wang^{2

4}

Affiliations

¹ School of Energy Science and Engineering, Central South University, Changsha, Hunan 410083, China.
² WA School of Mines: Minerals, Energy and Chemical Engineering (WASM-MECE), Curtin University, Perth, Western Australia 6845, Australia.
³ School of Engineering, Edith Cowan University, Joondalup, Western Australia 6027, Australia.
⁴ School of Chemical Engineering, The University of Adelaide, Adelaide, South Australia 5005, Australia.

Abstract

With increasingly severe air pollution brought by volatile organic compounds (VOCs), the search for efficient adsorbents toward VOC removal is of great significance. Herein, an adenine-based metal-organic framework, namely, bio-MOF-11 [Co₂(ad)₂(CH₃CO₂)₂·0.3EtOH·0.6H₂O, ad = adeninate], was synthesized via a facile method, and its VOC adsorption was reported for the first time. This novel bio-MOF-11 was investigated by employing four common VOCs (i.e., methanol, acetone, benzene, and toluene) as adsorbates. The saturated adsorption capacity of these targeted VOCs on bio-MOF-11 was estimated to be 0.73-3.57 mmol/g, following the order: toluene < benzene < acetone < methanol. Furthermore, with the adsorption temperature increasing from 288 to 308 K, the saturated adsorption capacity was reduced by 7.3-35.6%. It is worth noting that acetone adsorption is most sensitive to temperature ascribed to its low boiling point and strong polar nature. Meanwhile, owing to the molecular sieve effect, the adsorption capacity appears negatively correlated to the size of VOC molecules. Besides, the abundant exposed nitrogen atoms and amino groups in bio-MOF-11 cavities facilitate the adsorption of polar VOC molecules. This work promotes the fundamental understanding and practical application of bio-MOF for adsorptive removal of VOCs.