The Application of Dicyandiamide in Hydrogen Peroxide Bleaching
The study on the application of dicyandiamide in hydrogen peroxide bleaching of soda-AQ wheat straw pulp was carried out.The results showed that dicyandiamide could enhance hydrogen peroxide delignification performance and improve the brightness of the pulps bleached by OHP and OQPo low pollution bleaching sequences.The conditions of hydrogen peroxide bleaching in OHP sequence were as follows: temperature 85℃,reaction time 120minutes,pulp concentration 10％,NaOH 0.4％,MgSO4 0.5％,Na2SiO3 3％,H2O2 4％.The temperature of pressurized hydrogen peroxide bleaching in OQPo sequence was 100℃.During the total 120 minutes of reaction time,the reaction time with 0.6MPa oxygen pressure was 40 minutes.Other conditions were same as the hydrogen peroxide bleaching conditions in OHP sequence.Dicyandiamide was added in the pulp for five minutes and then hydrogen peroxide bleaching in OHP and OQPo sequence was carried out.The results showed that 1％ dicyandiamide charge was optimal for the delignification and brightness development,the addition of 1％ of dicyandiamide could increase the brightness about 3％ISO and 4％ISO,respectively for the OHP and OQPo sequences,and the viscosity of the bleached pulp was still kept in a high level.
dicyandiamide soda-AQ wheat straw pulp pretreatment hydrogen peroxide bleaching low pollution
ZENG JIAN LI WEIWEI LI JUN MO LIHUAN CHEN KEFU
Guangdong Public Laboratory of Paper Technology and Equipment,South China University of Technology,Guangzhou,Guangdong,510640,China;State Key Lab of Pulp and Paper Engineering,South China University of Technology,Guangzhou,Guangdong,510640,China
国际会议
第二届国际造纸与环境学术会议(The Second International Papermaking & Environment Conference)
天津
英文
454-457
2008-05-14（万方平台首次上网日期，不代表论文的发表时间）