Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference (한국펄프종이공학회:학술대회논문집)
- 2000.11a
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- Pages.15-21
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- 2000
Chlorte Reduction in $ClO_2$ Prebleaching by the Addition of HClO Scavengers
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Yoon, Byung-Ho
(Dept. of Paper Sci. & Eng., Kangwon National University) ;
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Lee, Myoung-Ku
(Dept. of Paper Sci. & Eng., Kangwon National University) ;
- Wang, Li-Jun (Dept. of Paper Sci. & Eng., Kangwon National University)
- Published : 2000.11.01
Abstract
In chlorine dioxide delignification and bleaching the formation of chlorate is undesirable because it does not react with lignin and is harmful to the environment. Chlorate is mainly formed from the in-situ generated hypochlorus acid which is also the main reason for AOX formation. In previous literature scavengers of hypochlorous acid such as sulfamic aicd, DMSO, and hydrogen peroxide have been added to bleaching stages to reduce AOX formation but less attention has been paid to chlorate reduction. This paper thus focuses on the reduction of chlorate content caused by the following additives, sulfamic acid, DMSO, hydrogen peroxide, and oxalic acid. The results show that only sulfamic acid and DMSO reduce chlorate formation under our chlorine dioxide prebleaching conditions. Results by UV spectroscopy and pH adjustment show that scavengers react with hypochlorous acid much faster than with chlorine. Hydrogen peroxide and oxalic acid react with HClO/
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