Deactivation mechanism of the simultaneous removal of carbonyl sulphide and carbon disulphide over Fe–Cu–Ni/MCSAC catalysts

Abstract

The deactivation mechanism of the simultaneous removal of COS and CS 2 over a Fe-Cu-Ni/MCSAC catalyst was investigated using SEM/EDS, XPS and in situ DRIFTS methods. The results show that the catalytic hydrolysis of COS and CS 2 over the Fe-Cu-Ni/MCSAC catalyst involves two steps: hydrolysis of COS/CS 2 and oxidation of H 2 S. The SEM/EDS and XPS results indicate that that catalytic hydrolysis of CS 2 can be achieved by the actions of alkaline groups and active components. When O 2 was introduced into the system, oxidation of H 2 S occurred viaH 2 S → S → SO 2− 4 /sulphate. In situ DRIFTS experiments indicated that the formation of sulphate may occur as follows: (a) H 2 S + O 2 → S + H 2 O, (b) S+O 2 → SO , (c)-COO+H 2 S →-CH+S-O, (d) C-OH+H 2 S →-CH+S-O. The in situ DRIFTS experiments also indicated that the C-OH groups,-COO groups and O 2 played important roles in the deactivation of the catalyst, which was consistent with the XPS results. Meanwhile, the SO 2− 4 /sulphate content increased during the reaction, which led to its occupancy of the catalyst's surface activity sites. Additionally, the alkaline groups and active components were removed, which could also result in the deactivation of the catalysts. Keywords. Deactivation mechanism; simultaneous catalytic hydrolysis of CS 2 and COS; Fe-Cu-Ni/MCSAC catalyst; closed carbide furnace tail gas.

Sodium-treated sepiolite-supported transition metal (Cu, Fe, Ni, Mn, or Co) catalysts for HCHO oxidation

“…The presence of four component peaks was detected at 710.7, 724.0, 713.2, and 725.9 eV in the Fe 2p XPS spectrum. The components at 710.7 and 724.0 eV represented the Fe 2p3/2 and Fe 2p1/2 final states of the surface Fe 2+ species [29], respectively, whereas the peaks at 713.2 and 725.9 eV were attributed to the Fe 2p1/2 and Fe 2p3/2 final states of the surface Fe 3+ species. Therefore, both Fe 2+ and Fe 3+ species were present in the sample.…”

Research on the Catalytic Hydrolysis of COS by Fe−Cu/AC Catalyst and Its Inactivation Mechanism at Low Temperature**

“…The leading technologies for COS removal include organic amine solution absorption, [4] hydrogenation, [5] oxidation, [6] adsorption, [7] catalytic hydrolysis, [8] etc. Among these methods, an effective way of removing COS is catalytic hydrolysis with advantages of low reaction temperature requirement, low energy consumption, less side reaction, and higher conversion rate.…”

Experimental and Theoretical Studies on the Influence of Carrier Gas for COS Catalytic Hydrolysis over MgAlCe Composite Oxides

“…So far, catalytic hydrolysis method is regarded as the suitable way for the removal of COS because of high removal efficiency, low operation cost, and mild reaction condition. 7−11 The hydrolysis products of COS are CO 2 and H 2 S. 12−16 H 2 S can be removed more easily than COS. In our previous study, hydrotalcite-like compounds-derived MgAlCe composite oxides (MgAlCeO x ) show 100% COS removal efficiency under N 2 atmosphere condition.…”

“…However, the existence of COS is not conducive to the purification of CO, which leads to environmental pollution and equipment corrosion. − Therefore, it is important to remove COS from these industrial tail gases. So far, catalytic hydrolysis method is regarded as the suitable way for the removal of COS because of high removal efficiency, low operation cost, and mild reaction condition. − The hydrolysis products of COS are CO 2 and H 2 S. − H 2 S can be removed more easily than COS. In our previous study, hydrotalcite-like compounds-derived MgAlCe composite oxides (MgAlCeO x ) show 100% COS removal efficiency under N 2 atmosphere condition .…”