Inhibition of CO in Blast Furnace Flue Gas on Poisoning and Deactivation of a Ni/Activated Carbon Catalyst in COS Hydrolysis

Abstract

A new method for delaying or avoiding catalyst poisoning in COS catalytic hydrolysis was found by using one of the existing gas components in blast furnace flue gas: CO. In this work, wood-based activated carbon (AC) catalysts were prepared, and the experimental results of COS catalytic hydrolysis showed that 10% Ni/AC could completely hydrolyze COS in a N2 atmosphere within 380 min, while there was no obvious deactivation within 1200 min in a CO atmosphere. The corresponding characterization showed that the oxidation process of H2S to sulfate (SO4 2–) was inhibited, and it was easier to desorb from the catalyst surface in a CO atmosphere. Obvious electron transfer occurred on the catalyst surface, and the enrichment and conversion of sulfate (SO4 2–) on the catalyst surface were inhibited. The excellent durability in CO can be attributed to the inhibition of sulfate formation by the presence of CO and the supplement of hydroxyl consumed on the catalyst surface by the presence of H2O, which is the key factor to inhibit the poisoning or deactivation of the catalyst in COS hydrolysis.

Adsorption Behaviors of H2S and CO2 on the Synergistic Removal of HCl and Hg0 in Pyrolytic Waste Plastic Gas on 4Ca-1Co/CA

“…In addition, several characteristic peaks of CaSO 4 (PDF#74-1639) could be found at 25.5°, 29.5°, 43.0°, 47.4°, and 50.6° in the XRD spectrum, corresponding to (310), (400), (003), (601), and (313) crystal planes. It reveals that H 2 S dissociates and generates sulfate, which may block the pores and cause the adsorbent to deactivate. , …”

“…It reveals that H 2 S dissociates and generates sulfate, which may block the pores and cause the adsorbent to deactivate. 34,35 Further exploration on the compounds in the spent sample with (without) H 2 S is performed and shown in Figure 5, Figure S3, and Figure S4 by the XPS spectra. As illustrated in Figure 5a, the peaks located at 347.8 and 350.7 eV allocate to CaO, and the peaks centered at 348.2 and 351.4 eV correspond to CaSO 4 , which is consistent with the XRD results.…”

A study on the catalytic performance of the ZrO2@γ-Al2O3 hollow sphere catalyst for COS hydrolysis

“…After loading ZrO 2 , COS and H 2 O molecules fill the surface of the ZrO 2 @g-Al 2 O 3 hollow sphere hydrolysis catalyst through two processes of adsorption and transfer, and ZrO 2 can effectively enhance the overflow of the hydrolysis catalytic product H 2 S and to a certain extent avoid the decrease of hydrolysis catalytic activity due to H 2 S adsorption on the catalyst surface. [30][31][32][33][34] At appropriate humidity, COS mostly combines with -OH in the basic center of the ZrO 2 @g-Al 2 O 3 hollow sphere hydrolysis catalyst surface due to the ionic dipole to form intermediates, which later react with H 2 O molecules adsorbed in the active center of the catalyst surface to break the CQS double bond of COS molecules to form C-S, while the S in the C-S bond easily combines with -H ions in H 2 O molecules to form -SH, and with further reaction, COS is eventually hydrolyzed to H 2 S and CO 2 . The hydrolysis reaction is the key process in the whole process of hydrolysis catalysis.…”

The influence of H2O or/and O2 introduction during the low-temperature gas-phase sulfation of organic COS + CS2 on the conversion and deposition of sulfur-containing species in the sulfated CeO2-OS catalyst for NH3-SCR

“…pointed out that the hydrolysis activity of the catalyst was significantly low under an anhydrous atmosphere, and the reintroduction of H 2 O quickly improved the hydrolysis activity. 15 However, the presence of excess H 2 O hindered the reaction between organic sulfur and active components of the catalyst owing to the formation of a water film and reduced the hydrolysis of COS and CS 2 because of the competitive adsorption of H 2 O with organic sulfur on the surfaces of the catalysts. [16][17][18] Simultaneously, the enhancement of O 2 concentration during the hydrolysis process also made the hydrolysis activity of organic COS and CS 2 first increase and then decrease.…”