Removal of hexenuronic acid by xylanase to reduce adsorbable organic halides formation in chlorine dioxide bleaching of bagasse pulp.
Xylanase-aided chlorine dioxide bleaching of bagasse pulp was investigated. The pulp was pretreated with xylanase and followed a chlorine dioxide bleaching stage. The ATR-FTIR and XPS were employed to determine the surface chemistry of the control pulp, xylanase treated and chlorine dioxide treated pulps. The hexenuronic acid (HexA) could obviously be reduced after xylanase pretreatment, and the adsorbable organic halides (AOX) were reduced after chlorine dioxide bleaching. Compared to the control pulp, AOX could be reduced by 21.4-26.6% with xylanase treatment. Chlorine dioxide demand could be reduced by 12.5-22% to achieve the same brightness. The ATR-FTIR and XPS results showed that lignin and hemicellulose (mainly HexA) were the main source for AOX formation. Xylanase pretreatment could remove HexA and expose more lignin, which decreased the chlorine dioxide demand and thus reduced formation of AOX.
College of Light Industry and Food Engineering, Guangxi University, Nanning 530004, PR China; Department of Chemical Engineering, University of New Brunswick, Fredericton, NB E3B5A3, Canada.
Shuangxi
S
Nie
College of Light Industry and Food Engineering, Guangxi University, Nanning 530004, PR China.
Shuangfei
S
Wang
College of Light Industry and Food Engineering, Guangxi University, Nanning 530004, PR China.
Chengrong
C
Qin
College of Light Industry and Food Engineering, Guangxi University, Nanning 530004, PR China.
Shuangquan
S
Yao
Department of Chemical Engineering, University of New Brunswick, Fredericton, NB E3B5A3, Canada.
Johnbull Friday
JF
Ebonka
College of Light Industry and Food Engineering, Guangxi University, Nanning 530004, PR China; Department of Chemical Engineering, University of New Brunswick, Fredericton, NB E3B5A3, Canada. Electronic address: sx_ping@163.com.
Xueping
X
Song
Department of Chemical Engineering, University of New Brunswick, Fredericton, NB E3B5A3, Canada.
Kecheng
K
Li
D000327:Adsorption; D002482:Cellulose / Q000737:chemistry*; D017606:Chlorine Compounds / Q000737:chemistry*; D006603:Hexuronic Acids / Q000737:chemistry* / Q000302:isolation & purification; D008031:Lignin / Q000737:chemistry; D010087:Oxides / Q000737:chemistry*; D056951:Photoelectron Spectroscopy; D017550:Spectroscopy, Fourier Transform Infrared; D014995:Xylosidases / Q000737:chemistry*
D017606:Chlorine Compounds; D006603:Hexuronic Acids; D010087:Oxides; C095263:hexenuronic acid; C025109:chlorine dioxide; D002482:Cellulose; D008031:Lignin; C027433:bagasse; D014995:Xylosidases
AOX formation; Bagasse pulp; Chlorine dioxide bleaching; Surface chemistry; Xylanase