Removal of CH₃SH with in‐situ generated ferrate(VI) in a wet‐scrubbing reactor

Abstract

BACKGROUND A wet scrubbing process with in‐situ electro‐generation of ferrate(VI) has been developed for removing odour from foul gas in wastewater treatment plants. In this process, methyl mercaptan (CH3SH) in synthetic gas is removed through absorption and oxidation by contacting the gaseous stream with aqueous NaOH electrolyte that offers in‐situ generation of ferrate(VI). RESULTS The process parameters including electrolyte concentration, applied current density, initial CH3SH concentration, gas flow rate and gaseous CH3SH compositions were investigated to determine the best operating conditions and design parameters for a scale‐up design. Under all the experimental conditions, gaseous CH3SH was completely removed by the wet scrubbing process at room temperature and atmospheric pressure. The process proved to be quite effective for dissolved CH3S‐ degradation under the optimum experimental condition at the NaOH concentration of 6 mol L–1, current density of 2.22 mA cm‐2 and CH3SH loading below 30 g m‐3 h‐1. A very short contact time of 0.06 s between the gas and the liquid phases was achieved in this in‐situ ferrate(VI) generation reactor. CONCLUSIONS This process is effective for CH3SH control, and holds great promise for industrial applications due to its high efficiency, simplicity and stability. © 2013 Society of Chemical Industry

Current Status and Outlook of Odor Removal Technologies in Wastewater Treatment Plant

“…Alfonsín et al [27] also pointed out that CS presented the highest impacts in freshwater eutrophication, photochemical oxidant formation, human toxicity and ecotoxicity due to the use of large amounts of chemicals. H 2 O 2 is a promising oxidant except for its instability in basic aqueous solution and the low efficiency of CH 3 SH removal [48,49]. The emerging oxidants of CS like peroxymonosulfate (PMS) has a similar structure with H 2 O 2 but the oxidation-reduction potential is stronger than H 2 O 2 [50].…”

Nanocellulose–Zeolite Composite Films for Odor Elimination

“…6,7 Packaging solutions for odor removal that utilizes commercially available adsorbents e.g. zeolites, activated alumina, activated carbon, silica, sodium bicarbonate, and titanium oxide have been developed and reported in the scientific and patent literature.…”

Ferrate(VI): A Green Molecule in Odorous Gas Treatment

“…In recent years, studies have been made to remove methyl mercaptan (CH 3 SH) by in-situ electrochemically generated ferrate(VI) (14,55,56). Several parameters of the in-situ process were studied, which included electrolyte concentration, applied current density, and initial CH 3 SH concentration in gaseous and aqueous phases.…”

“…One is dry processes, which include cold plasma, UV, thermal, and activated carbon adsorption (10)(11)(12)(13). The second is wet processes such as biological (biofilters or bioscrubbers) and absorption (chemical scrubbers) (6,14). In the chemical scrubbing process, odorants are oxidized rapidly in aqueous media and then oxidized by oxidants.…”