Effect of Activated Carbon Supports on Removing H₂S from Coal-Based Gases using Mn-Based Sorbents

Abstract

A series of MnO x /AC sorbents were prepared by a sub-or supercritical water impregnation method at different temperatures using three types of active carbons (ACs) as supports. The desulfurization activities of the MnO x /AC sorbents were studied, and the physicochemical properties of fresh and used sorbents were characterized by X-ray diffraction analysis, X-ray photoelectron spectroscopy, scanning electron microscopy, and X-ray absorption near edge structure. The results indicate that the AC composition and preparing temperature affect the desulfurization activity of prepared sorbent by changing the form and dispersion of the active component. MnO x /AC sorbent prepared at 350°C and active carbon AC(Z) from walnut shell as support presents the best desulfurization activity, holding above 22 h under the desulfurization level of nearly entire removing H 2 S in hot coal-based gas with breakthrough sulfur capacity of 7.24 g of S/100 g of sorbent. It is found that the valence of Mn loaded on the different AC supports was various, which related directly to the activity and capacity of the H 2 S removal from hot coal-based gases. The species, content, and the dispersion of the manganese oxide on the surface of the supports were dominated by AC properties. In addition, Mn 3 O 4 is the main active component for the H 2 S removal over MnO x /ACs sorbents.

Activated Carbon and Attapulgite as Adsorbent Composite Carrier for Removing H2S at Low Temperature

“…prepared MnOx/AC adsorbents by impregnation method with three activated carbons as the carriers, and removed 500 ppm H 2 S simulated gas at 350 °C and GHSV 2000 h −1 . The results showed that the adsorbent agent that walnut shell activated carbon was used as carrier has a breakthrough time of 22 h and a sulfur capacity of 72.4 mg g −1 …”

Utilization of cocoa activated carbon for trimethylamine and hydrogen sulfide gas removals in a confined space and its techno‐economic analysis and life‐cycle analysis

“…Compared with other studies, Lee et al reported that TMA adsorption capacity was obtained around 110 mg/g using base or acid‐modified activated carbon. In case of H 2 S adsorption, the maximum adsorption capacity was 72.4 mg/g at 350°C using MnO impregnated activated carbon . In addition, the adsorption of TMA and H 2 S was conducted using the activated carbon derived from rice husk with chemical activation of KOH .…”

“…In case of H 2 S adsorption, the maximum adsorption capacity was 72.4 mg/g at 350 C using MnO impregnated activated carbon. 65 In addition, the adsorption of TMA and H 2 S was conducted using the activated carbon derived from rice husk with chemical activation of KOH. 17 The adsorption capacity for TMA and tion capacity of 654.8 mg/g was much higher than other studies and H 2 S adsorption capacity of 220.37 mg/g is just lower than 410.8 mg/g (our previous study), 17 but still much higher than that of other studies.…”

Effect of lignite as support precursor on deep desulfurization performance of semicoke supported zinc oxide sorbent in hot coal gas

“…The porous supports mainly contain g-Al 2 O 3 , mesoporous silica, zeolite, and carbon materials. [21][22][23][24][25][26][27] Carbon materials including activated carbon and semicoke have attracted more and more researchers' attention due to their abundant pore structure and low cost. In comparison with activated carbon, semicoke is cheaper and more easily attained.…”