Difference in adsorbable organic halogen formation between phenolic and non-phenolic lignin model compounds in chlorine dioxide bleaching

Lisheng Shi; Jiayan Ge; Fuqiang Zhang; Shuangxi Nie; Chengrong Qin; Shuangquan Yao

doi:10.1098/rsos.191202

Difference in adsorbable organic halogen formation between phenolic and non-phenolic lignin model compounds in chlorine dioxide bleaching

R Soc Open Sci. 2019 Oct 9;6(10):191202. doi: 10.1098/rsos.191202. eCollection 2019 Oct.

Authors

Lisheng Shi^{1

2}, Jiayan Ge^{1

2}, Fuqiang Zhang^{1

2}, Shuangxi Nie^{1

2}, Chengrong Qin^{1

2}, Shuangquan Yao^{1

2}

Affiliations

¹ College of Light Industrial and Food Engineering, Guangxi University, Nanning 530004, People's Republic of China.
² Guangxi Key Laboratory of Clean Pulp & Papermaking and Pollution Control, Nanning 530004, People's Republic of China.

Abstract

Adsorbable organic halogen (AOX) is generally formed by the reaction of residual lignin in pulps with chlorine dioxide during bleaching. Lignin has a complex structure. Different functional groups and bonds are present in lignin structures. Phenolic hydroxyl is one of the important functional groups in lignin, and it significantly influences the chemical properties and reactivity. To study the effect of phenolic hydroxyl on AOX formation, vanillyl alcohol (VA) was selected as the phenolic lignin model compound, and veratryl alcohol (VE) was selected as the non-phenolic lignin model compound in this study. The kinetics of AOX formation by the reaction of VA or VE with chlorine dioxide was studied. The effects of pH, chlorine dioxide, lignin model compound concentration and reaction temperature on AOX formation are discussed. The activation energies of the reaction of VA and VE with chlorine dioxide are 16 242.47 J mol^-1 and 281.34 J mol^-1, respectively. Thus, we found that the non-phenolic lignin can react with chlorine dioxide to form AOX more easily than phenolic lignin.

Keywords: adsorbable organic halogen; bleaching; lignin model compound; vanillyl alcohol; veratryl alcohol.

Associated data

figshare/10.6084/m9.figshare.c.4683404