Effect of Co-B supporting methods on the hydrogenation of m-chloronitrobenzene over Co-B/CNTs amorphous alloy catalysts

Abstract

Carbon nanotubes (CNTs)-supported Co-B amorphous alloy catalysts, with selective deposition of Co-B particles inside or outside of CNTs (labeled as Co-B-in/CNTs and Co-B-out/CNTs), were prepared based on the difference in the interface energies of organic and aqueous solutions with the CNTs surface. The catalysts were tested for the liquid-phase hydrogenation of m-chloronitrobenzene (m-CNB) to m-chloroaniline. Compared with Co-B-out/CNTs, Co-B-in/CNTs shows smaller, homogeneous size, and greatly improved thermal stability. The hydrogenation of m-CNB over Co-B-out/CNTs occurs on the outside of CNTs, while the hydrogenation of m-CNB over Co-B-in/CNTs occurs in the nanospace inside of CNTs. Co-B-in/CNTs exhibits a much higher activity than Co-B-out/CNTs.