Mesoporous silica gel doped with dysprosium and modified with copper: A selective catalyst for the hydrogenation of 1-hexyne/1-hexene mixture

The selective hydrogenation of 1-hexyne/1-hexene mixture in the temperature range 100-140 degrees C and a hydrogen pressure of 3 atm was studied on catalysts based on mesoporous silica gel modified with copper and mesoporous silica gel doped with dysprosium and modified with copper. The physicochemical characteristics of the samples were studied by low temperature nitrogen adsorption-desorption method, scanning electron microscopy (SEM), X-ray fluorescence (XRF), and inductively coupled plasma mass spectrometry (ICP-MS). In addition, theoretical calculations of the entropies and energies of formation of activated complexes of the hydrogenation reactions of 1-hexyne and 1-hexene in the gas phase have been calculated with Gaussian 09 software using the density functional theory (DFT) B3LYP/cc-pVQZ method. It was found that the presence of dysprosium in the structure of mesoporous silica gel leads to an increase in catalytic activity in the hydrogenation of 1-hexyne. Moreover, it was shown that mesoporous silica gel modified with copper has the highest selectivity for hexene-1 in the hydrogenation reaction of 1-hexyne/1-hexene mixture at 130 degrees C.