Sander Van Donk

A novel method of monitoring the sulfidation of hydrotreating catalysts: the conversion of carbonyl sulfide

During the sulfidation of hydrotreating catalysts under a H2S/H2 flow, the conversion of carbonyl sulfide (COS), present as an impurity, allows one to determine the starting and ending temperatures of the formation of the active sulfide phase. This new and simple method is validated by comparing it with CO adsorption monitored by IR spectroscopy for two CoMo catalysts sulfided either after calcination or after drying. Both methods show that the formation of CoMoS sites occurs at higher temperature when the catalyst is dried instead of calcined before the sulfidation.

From Gas to Liquid Phase Sulfidation: An IR Spectroscopy Study

A side by side characterization of gas and liquid phase activation of a CoMo/Al2O3 hydrodesulfurization (HDS) catalyst is reported using thiophene HDS as a test reaction and CO adsorption monitored by infrared spectroscopy. The liquid phase sulfidation (high pressure, dimethyldisulfide) leads to the formation of CoMoS sites with higher intrinsic activity compared to the gas phase (H2S/H2).Graphical AbstractAs compared to the classical gas phase (H2S/H2), the liquid phase sulfidation (high pressure, feed, dimethyldisulfide) changes drastically the spectrum of CO adsorbed on the CoMo/Al2O3: the band attributed to CO in interaction with CoMoS sites is downward shifted (−17 cm−1) while its intensity is decreased