Polyoxometalates Immobilized on Covalent Triazine Framework as Efficient Catalysts for Deep Oxidative Desulfurization
Chengpeng Liu, Zhen Li, Huifang Liu, Jing Dong, Yingnan Chi, Changwen Hu
Abstract
Abstract The immobilized polyoxometalates (POMs) with evenly dispersed catalytic sites, amphiphilic surface, and excellent recyclability are highly desired in many important reactions. Herein, PMo 12 @CTF has been successfully fabricated by the electrostatic assembly of H 3 PMo 12 O 40 (PMo 12 ) with porous cationic covalent triazine framework (CTF), where PMo 12 are evenly dispersed on the support. The synthesized PMo 12 @CTF is highly active for oxidative desulfurization of diesel fuel and dibenzothiophene (DBT) can be completely converted in 2 h under mild conditions (40 °C) in a biphasic system. Impressively, the catalytic activity of heterogeneous PMo 12 @CTF (conversion: 100 %) is much higher than that of homogeneous PMo 12 (conversion: 20 %). The control experiments and contact angle measurements reveal that the CTF endows PMo 12 @CTF with large surface area and amphiphilic feature and the catalyst can effectively contact with both oxidant H 2 O 2 in extraction phase and DBT in oil phase. Moreover, PMo 12 @CTF is robust and its catalytic activity is basically maintained after ten cycles.