Ru-MOF enwrapped by montmorillonite for catalyzing benzene hydrogenation

In this work, the metal-organic frameworks of ruthenium [Ru-2(II,III)(BTC)(2)XXY1.5 - x] (BTC = 1,3,5-benzenetricarboxylate, X, Y = Cl- or OH-, termed as Ru-MOFs) that are grown on montmorillonite (Mt) in a solvothermal reaction, and a type of composite materials (Ru-MOF_Mt) with open channels have been fabricated. Due to the high pore volume, the Ru-MOF particles are found to greatly enlarge the surface area of the hybrid material. To activate the metal centers in the Ru-MOF, the hybrids are annealed in a flow of H-2 at mid-level temperatures (similar to 300 degrees C). With this H-2-annealing treatment the frameworks are found to be partly decomposed, and the coordinatively unsaturated sites (CUS) are produced. The annealed Ru-MOF Mt is highly efficient in catalyzing reactions of benzene hydrogenation. The turn-over frequency (TOF) of benzene to hexane reaches 3478 h(-1). This catalyst is able to be reused at least five times without any de-activation demonstrating that the CUS are readily protected by the Mt layers. (C) 2015 Elsevier B.V. All rights reserved.