Catalytic hydrogenation of 2,4-dinitroethylbenzene to 2,4-diaminoethylbenzene over Ni/HY catalysts: The solvent effect

• The hydrogenation of 2,4-DNEB exhibits better performance in protic solvents.
• The good performance is correlated with their higher H-bond donating capability.
• The hydrogenation can be accelerated in the mixed solvents of water and ethanol.

Catalytic hydrogenation of 2,4-dinitroethylbenzene over Ni/HY catalysts in different solvents was studied, which demonstrated that the reaction exhibits the best performance in protic solvents. The reason is hypothesized to be the strong hydrogen-bond interaction between the protic solvents with the reactant, intermediates and product due to their excellent hydrogen-bond donating capability, which favors the desorption of the adsorbed intermediates and product from the catalysts and helps to polarize the NO bonds of the reactant and intermediates. Subsequently, the hydrogenation in the mixed solvents of water and ethanol was investigated, which showed that the reaction can be significantly accelerated by adding water into ethanol and the optimum volume percentage of water is verified to be 40%.