Aqueous reactions of chlorine dioxide with hydrocarbons

Rav-Acha, Chaim; Choshen, Ehud

doi:10.1021/es00164a004

Cited by 28 publications

(21 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…1 Because many oxidizing agents currently used in the industry are selective [5][6][7] and air regulations require mass removal data, quantitative removal efficiency data based on individual compounds are required for design and optimization of air pollution control devices. In an industrial-scale wet scrubber using ClO 2 (pH 3.66 and 35°C), removal efficiencies were significantly higher for methanethiol compared with the aldehydes hexanal, 2-methylpropanal, 3-methylbutanal, and 2-methylbutanal.…”

Section: Discussionmentioning

confidence: 99%

“…5 Kinetic data suggest that typical oxidizing agents used in wet scrubbers (e.g., ClO 2 and O 3 ) do not react or react slowly with many of the VOCs in rendering plant waste gases. 6,7 However, the kinetics of reaction between ClO 2 (and other oxidizing agents) and the major VOCs fractions in rendering emissions have not been measured. Reaction rate constants ranging from 4 ϫ 10 4 to 3 ϫ 10 8 L/mol/sec are reportedly required to achieve rapid removal in wet scrubbers.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Effect of pH and Temperature on the Kinetics of Odor Oxidation Using Chlorine Dioxide

Kastner

Das

et al. 2003

Journal of the Air & Waste Management Association

View full text Add to dashboard Cite

Increasing public concerns over odors and air regulations in nonattainment zones necessitate the remediation of a wide range of volatile organic compounds (VOCs) generated in the poultry-rendering industry. Currently, wet scrubbers using oxidizing chemicals such as chlorine dioxide (ClO 2 ) are utilized to treat VOCs. However, little information is available on the kinetics of ClO 2 reaction with rendering air pollutants, limiting wet scrubber design and optimization. Kinetic analysis indicated that ClO 2 does not react with hexanal and 2-methylbutanal regardless of pH and temperature and implied that aldehyde removal occurs primarily via mass transfer. Contrary to the aldehydes, ethanethiol or ethyl mercaptan (a model compound for methanethiol or methyl mercaptan) and dimethyl disulfide (DMDS) rapidly reacted with ClO 2 . The overall reaction was found to be second and third order for ethanethiol and DMDS, respectively. Moreover, an increase in pH from 3.6 to 5.1 exponentially increased the reaction rate of ethanethiol (e.g., k 2 ϭ 25-4200 L/mol/sec from pH 3.6 to 5.1) and significantly increased the reaction rate of DMDS if increased to pH 9 (k 3 ϭ 1.4 ϫ 10 6 L 2 /mol 2 /sec). Thus, a small increase in pH could significantly improve wet scrubber operations for removal of odor-causing compounds. However, an increase in pH did not improve aldehyde removal. The results explain why aldehyde removal efficiencies are much lower than methanethiol and DMDS in wet scrubbers using ClO 2 .

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Effect of pH and Temperature on the Kinetics of Odor Oxidation Using Chlorine Dioxide

Kastner

Das

et al. 2003

Journal of the Air & Waste Management Association

View full text Add to dashboard Cite

show abstract

“…4 Kinetic data suggest that typical oxidizing agents used in wet scrubbers (e.g., ClO 2 and ozone) do not react or react slowly with many of the VOCs in rendering plant waste gases. 5,6 Reaction rates ranging from 4 × 10 4 to 3 × 10 8 (L/mol/sec) are reportedly required to achieve rapid removal in wet scrubbers. 4 Benzaldehyde, a representative aldehyde periodically measured in rendering emissions, 7 has a reported reaction rate of less than 3 × 10 -4 (L/mol/sec) with ClO 2 .…”

Section: Discussionmentioning

confidence: 99%

“…13 It is likely that periodic, incorrect mixing of the reactants 14 Most wet scrubber analysis in the rendering industry has been based on odor intensity, with little quantification of efficiency toward individual compounds, especially for industrial-scale wet scrubbers. 3 Because many oxidizing agents currently used in the industry are selective 5,6 and air regulations require mass removal data, quantitative removal efficiency data based on individual compounds is required for the design and optimization of air pollution control devices. For the compounds quantified, the total VOC removal efficiency ranged between 20 and 64% for both plants (see Tables 3, 4, and 6).…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Wet Scrubber Analysis of Volatile Organic Compound Removal in the Rendering Industry

Kastner

Das

2002

Journal of the Air & Waste Management Association

View full text Add to dashboard Cite

The promulgation of odor control rules, increasing public concerns, and U.S. Environmental Protection Agency (EPA) air regulations in nonattainment zones necessitates the remediation of a wide range of volatile organic compounds (VOCs) generated by the rendering industry. Currently, wet scrubbers with oxidizing chemicals are used to treat VOCs; however, little information is available on scrubber efficiency for many of the VOCs generated within the rendering process. Portable gas chromatography/mass spectrometry (GC/MS) units were used to rapidly identify key VOCs on-site in process streams at two poultry byproduct rendering plants. On-site analysis was found to be important, given the significant reduction in peak areas if samples were held for 24 hr before analysis. Major compounds consistently identified in the emissions from the plant included dimethyl disulfide, methanethiol, octane, hexanal, 2-methylbutanal, and 3-methylbutanal. The two branched aldehydes, 2-methylbutanal and 3-methylbutanal, were by far the most consistent, appearing in every sample and typically the largest fraction of the VOC mixture.A chlorinated hydrocarbon, methanesulfonyl chloride, was identified in the outlet of a high-intensity wet scrubber, and several VOCs and chlorinated compounds were identified in the scrubbing solution, but not on a consistent basis. Total VOC concentrations in noncondensable gas streams ranged from 4 to 91 ppmv. At the two plants, the odor-causing compound methanethiol ranged from 25 to 33% and 9.6% of the total VOCs (v/v). In one plant, wet scrubber analysis using chlorine dioxide (ClO 2 ) as the oxidizing agent indicated that close to 100% of the methanethiol was removed from the gas phase, but removal efficiencies ranged from 20 to 80% for the aldehydes and hydrocarbons and from 23 to 64% for total VOCs. In the second plant, conversion efficiencies were much lower in a packed-bed wet scrubber, with a measurable removal of only dimethyl sulfide (20-100%). INTRODUCTIONPoultry rendering operations convert organic wastes (feathers, offal, dead birds, blood, hatchery byproducts, etc.) to products such as feed additives and fertilizer. In poultry rendering operations, feathers are typically hydrolyzed in batch mode at 140-150 ºC (276-345 kPa) for 20-45 min to breakdown the keratin, 1 and the meat byproducts or offal are typically treated at 121-135 ºC (172-517 psig) with varying residence times depending on the mode of operation, batch or continuous. 2,3 In some cases, the hydrolyzed feathers are then combined with offal and dried. In both of these steps, volatile organic compounds (VOCs) are generated, some of which are odorous. Overhead vapors from the feather hydrolyzer and driers are passed through condensers to remove some VOCs. The noncondensable gases typically are passed through wet scrubber units to remove the VOC fraction not removed in the condensers.

show abstract

Reactions of PAH with Chlorine and Chlorine Dioxide in Coal Tar Lined Pipes

Merkel¹,

Maier²,

Sacher³

et al. 1998

Acta hydrochim. hydrobiol.

View full text Add to dashboard Cite

In presence of disinfectants, PAH are remobilized from the coal tar lining of water distribution mains. Reactions of the PAH with chlorine and chlorine dioxide can lead to chlorinated PAH that might show higher mutagenic effects than the parent PAH. The application of the solid‐phase microextraction as a sampling preparation method in combination with a gas chromatographic mass spectrometric device is a reliable and useful method to achieve detection limits in the lower nanogramme‐per‐liter level for PAH and chlorinated PAH. Thus, the reactions of four PAH (anthracene, fluoranthene, fluorene, and phenanthrene) with chlorine and chlorine dioxide under conditions prevalent in drinking water distribution systems could be investigated. In batch experiments with demineralized and drinking water at pH 7, the concentrations of fluoranthene, fluorene, and phenanthrene remained constant, whereas anthracene reacted quantitatively with both disinfectants. In these reactions, no chlorinated products could be detected, only mono‐hydroxyanthracene and anthraquinone were formed. A reaction mechanism for both reaction products is proposed. The results suggest that oxidation is the major pathway of the reaction of PAH with disinfectants in the systems under investigation.

show abstract

Aqueous reactions of chlorine dioxide with hydrocarbons

Cited by 28 publications

References 11 publications

Effect of pH and Temperature on the Kinetics of Odor Oxidation Using Chlorine Dioxide

Effect of pH and Temperature on the Kinetics of Odor Oxidation Using Chlorine Dioxide

Wet Scrubber Analysis of Volatile Organic Compound Removal in the Rendering Industry

Reactions of PAH with Chlorine and Chlorine Dioxide in Coal Tar Lined Pipes

Contact Info

Product

Resources

About