Study of Calcium-Based Sorbents for High-Temperature H2S Removal. 1. Kinetics of H2S Sorption by Uncalcined Limestone

Simultaneous Production of High-Purity Hydrogen and Sequestration-Ready Co2 From Syngas

“…Fenouil [36][37][38] Borgwardt [40] determined that the combined effects of H 2 O and CO 2 on the sintering of CaO at a given temperature were greater than the summative effect of each gas alone, and surface area loss was more strongly affected than porosity. It was determined that grain boundary and surface diffusion mechanisms were responsible.…”

Trends in Research and Technical Development of Sorbents for Hot Gas Desulfurization for H2S Removal

“…그러나 석회석은 전 세계적으로 널리 분포하는 광물 중 하나이며 석회석의 소성 후 얻어지는 CaO는 고온건식탈황에서 이론적으로 95% 이상의 높은 황 제거율을 가진다고 보고되고 있을 뿐만 아니라, 30) 수 mm 입도가 되더라도 빠르고 완전하게 CaS로 전환 되기 때문에, 아직까지 칼슘계 탈황제에 대한 많은 연 구가 이루어지고 있는 상황이다. …”

Hot Gas Clean‐Up with Dolomites: Effect of Gas Composition on Sulfur Removal Activity

“…Unreactive MgO in the matrix hinders sintering of CaO and CaS, and facilitates gas diffusion within the solid. Consequently, dolomite has a higher H 2 S removal efficiency than limestone . However, due to thermodynamic constraints, the H 2 S removal efficiencies of calcium containing sorbents are about 90 % under typical coal gasification conditions, resulting in residual H 2 S levels of 100 ppmv (0.1 dm 3 /m 3 ) or greater.…”

“…Specific activities of copper and cobalt-based catalysts that are used in methanol and Fischer-Tropsch fuel synthesis, respectively, significantly degrade in the presence of H 2 S. The H 2 S level is required to be lower than 1 ppmv for most applications. [1][2][3][4] Therefore, in many cases, it would be necessary to reduce the H 2 S concentration from several percentages to a few ppmv levels.…”

“…Consequently, dolomite has a higher H 2 S removal efficiency than limestone. [1,4,[10][11][12] However, due to thermodynamic constraints, the H 2 S removal efficiencies of calcium containing sorbents are about 90 % under typical coal gasification conditions, resulting in residual H 2 S levels of 100 ppmv (0.1 dm 3 /m 3 ) or greater. Therefore, these sorbents are mostly preferred for bulk H 2 S removal and an additional downstream guard bed of proper sorbent is needed for further sulfur polishing.…”