Catalytic oxidation of S(IV) in seawater slurries of activated carbon

Journal Article · Fri Jul 01 00:00:00 EDT 2005 · Environmental Science and Technology

DOI:https://doi.org/10.1021/es048929x· OSTI ID:20638440

Vidal, B F; Ollero, P; Gutierrez Ortiz, F J; Arjona, R ^[1]

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1. University of Seville, Sevilla (Spain). Department of Chemical and Environmental Engineering

Flue gas desulfurization (FGD) by means of SO{sub 2} absorption in seawater is a well-known process with a main drawback; due to the low S(IV) oxidation rate at the low pH values of the absorption tower effluent, a large oxidation basin is required. Laboratory reactor tests, in which a commercially available activated carbon was used, showed a significant catalytic effect. It is shown that the kinetic equation for the catalytic oxidation of S(IV), in seawater slurries of activated carbon, is first-order with respect to S(IV) and zero-order with respect to oxygen. The dependence of the kinetic constant with respect to pH, temperature, and catalyst size particles were also obtained. The study showed that using an appropriated size and concentration of catalyst, it is possible to reach, at pH = 4, S(IV), oxidation rates similar to those obtained at pH = 6 without catalyst. Operating at pH = 4 requires less seawater flow rate in the oxidation basin than at pH = 6. Thus, the volume of the water treatment plant can be reduced too. The space requirements and both the capital and the operating cost are lower, a critical issue concerning the retrofitting of existing power stations. 12 refs., 9 figs., 3 tabs.

• OSTI ID: 20638440
• Journal Information: Environmental Science and Technology, Vol. 39, Issue 13; Other Information: [e-mail]; ISSN 0013-936X
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
20 FOSSIL-FUELED POWER PLANTS
ACTIVATED CARBON
FLUE GAS
DESULFURIZATION
SULFUR DIOXIDE
ABSORPTION
SEAWATER
CHEMICAL REACTION KINETICS
OXIDATION
SULFUR
SLURRIES
CATALYSIS
CATALYSTS
PARTICLE SIZE
CATALYTIC EFFECTS
TEMPERATURE DEPENDENCE
FLOW RATE
COASTAL REGIONS
DEACTIVATION
FOSSIL-FUEL POWER PLANTS
COST
WATER TREATMENT PLANTS