Reaction kinetics and simulation models for novel high-temperature desulfurization sorbents: Final report
A kinetic study of two mixed-metal oxide sorbents (zinc ferrite and zinc titanate) was conducted to obtain kinetic data at the temperatures and pressures typically encountered in coal gasifiers. These sorbents are used to remove H/sub 2/S from the hot coal- derived gases and can be subsequently regenerated for use in a cyclical operation. The qualitative behavior of zinc titanate was found to be quite similar. Sulfidation kinetic rate increased with H/sub 2/S concentration, slightly increased with temperature, increased with pressure at a constant H/sub 2/S mol fraction with pressure at a constant H/sub 2/S partial pressure, and increased with decreasing pellet diameter. The regeneration rates of both zinc ferrite and zinc titanate increased with temperature, O/sub 2/ concentration, and pressure at a constant O/sub 2/ mole fraction. The formation of zinc sulfate was found to be significant during regeneration of zinc ferrite at sufficiently low temperatures, high pressures, and high O/sub 2/ concentrations. Reducing gas concentrations of 65-75% (H/sub 2/ + CO) simulating the output from the Texaco gasifier operated in the oxygen-blown mode were used to assess the impact on sorbent performance. The shrinking core kinetic model was found to fit the experimental data very well. Correlations were made using a priori estimates of all parameters including diffusivity and mass transfer coefficients. Quantitative agreement was best obtained by treating the diffusivity term and/or the mass transfer term as best fit parameters. 22 refs., 69 figs., 18 tabs.
- Research Organization:
- RTI International, Durham, NC (United States); Louisiana State Univ., Baton Rouge (USA)
- DOE Contract Number:
- AC21-87MC24160
- OSTI ID:
- 6381431
- Report Number(s):
- DOE/MC/24160-2671; ON: DE89000950
- Resource Relation:
- Other Information: Portions of this document are illegible in microfiche products
- Country of Publication:
- United States
- Language:
- English
Similar Records
Integration and testing of hot desulfurization and entrained-flow gasification for power generation systems. Volume 2, Evaluation of zinc loss from zinc titanate sorbents during hot gas desulfurization: Final report, October 1, 1987--October 31, 1993
Bench-scale testing of novel high-temperature desulfurization sorbents: Final report
Related Subjects
COAL GAS
DESULFURIZATION
FERRITES
SORPTIVE PROPERTIES
SULFIDATION
REACTION KINETICS
TITANATES
ZINC COMPOUNDS
HOT GAS CLEANUP
MECHANICAL PROPERTIES
POROSITY
PRESSURE EFFECTS
PROGRESS REPORT
REGENERATION
SORPTION
TEMPERATURE EFFECTS
CHEMICAL REACTIONS
DOCUMENT TYPES
FERRIMAGNETIC MATERIALS
FLUIDS
GASES
IRON COMPOUNDS
KINETICS
MAGNETIC MATERIALS
MATERIALS
OXYGEN COMPOUNDS
PURIFICATION
SURFACE PROPERTIES
TITANIUM COMPOUNDS
TRANSITION ELEMENT COMPOUNDS
010800* - Coal
Lignite
& Peat- Waste Management
010404 - Coal
Lignite
& Peat- Gasification