High Efficient Bleaching of Old Newsprint Deinked Pulp
The efficiency of three chlorine-free bleaching chemicals,hydrogen peroxide(H2O2,P),sodium hydrosulfite(Na2S2O4,Y)and formamidine sulphinic acid(FAS,F),as well as their different combinations on old newsprint deinked pulp was investigated.The experimental results showed that the final brightness after bleaching was greatly influenced by the effective residual ink concentration(ERIC)of the deinked pulp.The pulp with more residual inks was more difficult to be bleached to a higher brightness.In the single stage H2O2 bleaching of the old newsprint deinked pulp,the highest brightness could be obtained when 40％ of the total dosage was used during the pulping process.Compared to H2O2and Na2S2O4 bleaching,FAS bleaching gave the highest brightness,b* of the deinked pulp decreased after bleaching with FAS and NaES2O4.The brightness of the deinked pulp could reach 60.0％ISO when two-stage bleaching sequences P-P,P-Y,P-F were used.Among these sequences,the P-F sequence gave the highest brightness.
old newsprint deinked pulp bleaching
QINGHUA XU YINGJUAN FU QUAN LIN ZHIYONG SHAO
Shandong Institute of Light Industry,Changqing,Jinan,Shandong,P.R.China School of Printing and Packaging,Wuhan University,P.R.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
479-481
2008-05-14（万方平台首次上网日期，不代表论文的发表时间）