Kinetics of Mn-based sorbents for hot coal gas desulfurization: Quarterly progress report, December 15, 1994--March 15, 1995. Task 2 -- Exploratory experimental studies: Single pellet tests; Rate mechanism analysis
In earlier studies, zinc ferrite and zinc titanate were developed as regenerable sorbents capable of removing hydrogen sulfide from hot fuel gases originating from coal gasification. Manganese ore as well as manganese carbonate, precipitated from aqueous solutions, combined with alumina to form indurated pellets hold promise of being a highly-effective, inexpensive, regenerable sorbent for hot fuel gases. Although the thermodynamics for sulfur removal by manganese predicts somewhat higher hydrogen sulfide over-pressures (i.e. poorer degree of desulfurization) than can be accomplished with zinc-based sorbents, zinc tends to be reduced to the metallic state under coal gasification conditions resulting in loss of capacity and reactivity by volatilization of reactive surfaces. This volatilization phenomenon limits the temperatures for which desulfurization can be effectively accomplished to less than 500 C for zinc ferrite and 700 C for zinc titanate; whereas, manganese-based sorbents can be utilized at temperatures well in temperatures exceeding 700 C. Also the regeneration of manganese-based pellets under oxidizing conditions may be superior to that of zinc titanate since they can be loaded from a simulated reducing coal-derived gas and then be regenerated at higher temperatures (up to 1,300 C). The topics that will be addressed by this study include: preparation of an effective manganese-based sorbent, thermodynamics and kinetics of sulfur removal from hot fuel gases by this sorbent, analysis of kinetics and mechanisms by which sulfur is absorbed by the sorbent (i.e., whether by gaseous diffusion, surface-controlled reaction, ore pore diffusion), and cyclic sulfidation and regeneration of the sorbent and recovery of the sulfur.
- Research Organization:
- Minnesota Univ., Minneapolis, MN (United States). Dept. of Civil Engineering
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- FG22-94PC94212
- OSTI ID:
- 61095
- Report Number(s):
- DOE/PC/94212-T2; ON: DE95011393; TRN: AHC29516%%30
- Resource Relation:
- Other Information: PBD: 15 Mar 1995
- Country of Publication:
- United States
- Language:
- English
Similar Records
Kinetics of Mn-based sorbents for hot coal gas desulfurization. Quarterly progress report, September 15, 1995--December 15, 1995
Kinetics of Mn-based sorbents for hot coal gas desulfurization. Quarterly progress report, March 15, 1995--July 15, 1995
Related Subjects
FUEL GAS
HOT GAS CLEANUP
DESULFURIZATION
ADSORBENTS
MANGANESE ORES
SORPTIVE PROPERTIES
THERMODYNAMIC PROPERTIES
MANGANESE CARBONATES
PROGRESS REPORT
HYDROGEN SULFIDES
REMOVAL
ZINC COMPOUNDS
FERRITES
TITANATES
COMPARATIVE EVALUATIONS
CHEMICAL PREPARATION
CHEMICAL REACTION KINETICS
SORPTION
RECYCLING
SULFIDATION
REGENERATION
MATERIALS RECOVERY
PHASE DIAGRAMS
EXPERIMENTAL DATA