Efficient and versatile CuNi alloy nanocatalysts for the highly selective hydrogenation of furfural

The development of efficient and environmental benign non-noble bimetallic nanocatalysts is highly desirable and attractive in the upgrading of biomass-derived platform compounds to high-valued chemicals. A series of highly dispersed and versatile CuxNiy (x/y = 7:1, 3:1, 1:1, 1:3, 1:7) alloy supported nanocatalysts derived from layer double hydroxides (LDHs) precursors were fabricated and used for the selective hydrogenation of furfural to tetrahydrofurfuryl alcohol (THFA) and furfuryl alcohol (FOL). It was found that the chemical composition, preparation method and especially the reduction temperature of LDHs precursors greatly affected the properties of the resultant CuxNiy/MgAlO catalysts. Systematic characterizations revealed that the reduction temperature of catalyst precursor was closely related to the dispersion and homogeneous composition of CuNi alloy nanoparticle as well as the surface basicity of catalysts, which played crucial roles in achieving excellent catalytic performances. The optimized CuNi/MgAlO and Cu1Ni3/MgAlO nanocatalysts showed high activity and selectivity for the hydrogenation of furfural to THFA in ethanol compared with the monometallic Ni and the CuNi supported catalysts prepared with other methods, such enhanced catalytic performance was investigated to be enabled by the synergistic effect within the CuNi alloy nanoparticles. Interestingly, our bimetallic nanocatalysts could also realize efficient production of FOL from the selective hydrogenation of furfural at its aldehyde group by simply changing the solvent to methanol. Moreover, the bimetallic nanocatalysts showed good recyclability in the liquid phase hydrogenation. Our efficient and versatile CuNi alloy nanocatalysts not only provide promising candidates for effective upgrading of furfural but also broaden the application of non-noble bimetallic nanocatalysts for hydrogenative transformations.