Catalytic ozonation of gaseous reduced sulfur compounds using wood fly ash.
The feasibility of reusing wood ash as an inexpensive catalyst in a catalytic ozonation process has been demonstrated. Catalytic ozonation was demonstrated to oxidize H2S, methanethiol (MT), dimethyl sulfide (DMS), and dimethyl disulfide (DMDS) at low temperatures (23-25 degrees C). The process oxidized 25-50% of an inlet MT stream at 70 ppmv without the formation of DMDS (contrary to ash plus oxygen in air), oxidized 90-95% of an 85 ppmv stream of DMS, and oxidized 50% of a 100 ppmv DMDS stream using 2 g of wood ash at a space velocity of 720 h(-1) using ozone concentrations ranging from 100 to 300 ppmv. Similarly, 60-70% conversion of a 70 ppmv H2S stream was achieved with 2 g of ash in 1.1 s without catalytic deactivation (approximately 44 h). The overall oxidation rate of H2S, DMS, and DMDS increased with increasing ozone concentration contrary to the oxidation rate of MT, which was independent of ozone concentration. Dimethyl sulfoxide and dimethyl sulfone were identified as the primary end products of DMS oxidation, and SO2 was the end product of H2S and MT oxidation.
Kastner
James R
JR
Department of Biological and Agricultural Engineering, Driftmier Engineering Center, The University of Georgia, Athens, Georgia 30602, USA. jkastner@engr.uga.edu
Buquoi
Quentin
Q
Ganagavaram
Rangan
R
Das
K C
KC
D000393:Air Pollutants; D002384:Catalysis; D003247:Conservation of Natural Resources; D006862:Hydrogen Sulfide / Q000737:chemistry; D017745:Incineration; D010083:Oxidants, Photochemical / Q000737:chemistry*; D010084:Oxidation-Reduction; D010126:Ozone / Q000737:chemistry*; D013457:Sulfur Compounds / Q000737:chemistry*; D013458:Sulfur Dioxide / Q000737:chemistry; D014934:Wood
D000393:Air Pollutants; D010083:Oxidants, Photochemical; D013457:Sulfur Compounds; D013458:Sulfur Dioxide; D010126:Ozone; D006862:Hydrogen Sulfide