Abstract

The reaction between hypochlorous acid and chlorite ions is the rate limiting step for in situ chlorine dioxide regeneration. The possibility of increasing the speed of this reaction was analyzed by the addition of tertiary amine catalysts in the system at pH 5. Two amines were tested, DABCO (1,4-diazabicyclo[2.2.2]octane) and its derivative CEM-DABCO (1-carboethoxymethyl-1-azonia-4-aza-bicyclo[2.2.2]octane chloride). The stability of the catalysts in the presence of both reagents and chlorine dioxide was measured, with CEM-DABCO showing to be highly stable with the mentioned chlorine species, whereas DABCO was rapidly degraded by chlorine dioxide. Hence, CEM-DABCO was chosen as a suitable candidate to catalyze the reaction of hypochlorous acid with chlorite ions and it significantly increased the speed of this reaction even at low catalyst dosages. This research opens the door to a faster regeneration of chlorine dioxide and an improved efficiency in chlorine dioxide treatments.

Highlights

  • Tertiary amines are versatile compounds that can catalyze a wide range of organic (Ammer et al 2010) and oxidation reactions (Prütz 1998; Huang and Shah 2018)

  • Tertiary amines can be used as catalysts in polyurethane production (Sardon et al 2015), in the Baylis–Hillman reaction, enhancing the generation of new C–C bonds (Basavaiah et al 2010) and in water treatment

  • The first value corresponds to the pKa of CEM-DABCO, while the second inflection was likely caused by the alkali-catalyzed hydrolysis of the methyl ester and neutralization of the formed CM-DABCO (Dawson 2018)

Read more

Summary

Introduction

Tertiary amines are versatile compounds that can catalyze a wide range of organic (Ammer et al 2010) and oxidation reactions (Prütz 1998; Huang and Shah 2018). It is known that the addition of a tertiary amine such as DABCO (1,4-diazabicyclo[2.2.2]octane) to hypochlorous acid ( HOCl ) produces a highly reactive chlorommonium cation (Rosenblatt et al.1972). This chloroammonium cation can oxidize saturated structures faster than

Objectives
Methods
Results
Conclusion

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.