Keggin-POM@rht-MOF-1 composite as heterogeneous catalysts towards ultra-deep oxidative fuel desulfurization

Abstract POM@MOF composites have aroused much concern regarding their amazing catalytic performance, reliable stability and recyclability; however, it remains great challenge on synthesizing expected POM@MOF composites and catalyzing organic reactions. Herein, a series of three Keggin-POM@rht-MOF-1 (POM = H3+nPMo12-nVnO40, n = 1, (Mo11V1); n = 2, (Mo10V2); n = 3, (Mo9V3)), have been isolated by using a large internal cavity window of rht-MOF-1 to encapsulate the guest molecules of Keggin-POM. X-ray crystallographic analysis reveals that Keggin-POM@rht-MOF-1 composites are of high load efficiency and chemical stability. Upon employed as catalysts on the desulfurization reaction of model diesels and real diesels, the as-synthesized Keggin-POM@rht-MOF-1 composites exhibit high percent conversion of desulfurization up to 96% by Mo9V3 and 90% by Mo9V3, respectively. Its derivatives from both the advantages of the host of rht-MOF-1) and the Keggin-POM guest. The size-matched rht-MOF-1 prevented the leaching of Keggin-POM, while the Keggin-POM retain the reachability of dibenzothiophene (DBT), 1-benzothiophene (BT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT) for the catalyzing the oxidation reactions.