Fe/MCSAC catalysts surface modified with nitrogen DBD non-thermal plasma for carbonyl sulfide catalytic hydrolysis activity enhancement

The removal of carbonyl sulfide (COS or S=C=O) from gas streams over Fe/microwave coconut-shell activated carbon (MCSAC) catalysts modified by dielectric barrier discharge non-thermal plasma (NTP) were investigated. The properties of Fe/MCSAC catalysts modified by NTP in different conditions, included kinds of reactors, treatment times and input voltages. The surface properties were evaluated by means of energy-dispersive X-ray spectrometry, Brunauer Emmett Teller, X-ray photoelectron spectroscopy methods and theoretical calculation, which could help us understand the effects of the plasma treatment. The experiments results showed that the COS hydrolysis activities of Fe/MCSAC catalysts were largely enhanced after NTP modification. And the optimal reactor type, treatment time and input voltage were plate-plate type, 10 min and 35 V, respectively. The catalytic activity enhanced effectually due to the improvement of active component's dispersion after NTP modification. In addition, the extended oxygen functional groups on NTP-modified catalyst's surface could contribute to a higher activity for COS catalytic hydrolysis at low temperature. The investigation results indicate that non-thermal plasma treatment is an effective way to manipulate catalyst surface properties for COS catalytic hydrolysis reaction. Copyright (c) 2017 John Wiley & Sons, Ltd.