Ruthenium nanoparticles intercalated in hectorite: a reusable hydrogenation catalyst for benzene and toluene

The cationic organometallic aqua complexes formed by hydrolysis of [(C6H6)RuCl2]2 in water, mainly [(C6H6)Ru(H2O)3]2+, intercalate into sodium hectorite by ion exchange, replacing the sodium cations between the anionic silicate layers. The yellow hectorite thus obtained reacts in ethanol with mol. hydrogen (50 bar, 100°) with decompn. of the organometallic aqua complexes to give a black material, in which ruthenium(0) nanoparticles (9-18 nm) are intercalated between the anionic silicate layers, the charges of which being balanced by hydronium cations. The black ruthenium-modified hectorite efficiently catalyzes the hydrogenation of benzene and toluene in ethanol (50 bar H2, 50°), the turnover frequencies attaining 7000 catalytic cycles per h. [on SciFinder(R)]