发明名称 |
BLEACHING OF CHEMICAL PULP AND TREATMENT WITH A CHELATING AGENT |
摘要 |
The invention relates to a process for the bleaching of chemical pulp, wherein the pulp is delignified and/or bleached with chlorine dioxide or with a combination of chlorine dioxide and a per-compound, and additionally the pulp is chelated in order to bind heavy metals, such as Fe, Mn and/or Cu, to a chelate complex. The chelate complex is selected from the group made up of N-bis-[(1,2-dicarboxylethoxy)-ethyl]-amine, N-bis[(1,2-dicarboxylethoxy)-ethyl]-aspartic acid and N-tris-[(1,2-dicarboxylethoxy)-ethyl]-amine, and the alkali metal and earth-alkali metal salts of these, and the chelating treatments are carried out simultaneously by combining the chelating chemical with the pulp in the same bleaching stage as chlorine dioxide.
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申请公布号 |
WO9925919(A1) |
申请公布日期 |
1999.05.27 |
申请号 |
WO1998FI00887 |
申请日期 |
1998.11.13 |
申请人 |
KEMIRA CHEMICALS OY;JAEKAERAE, JUKKA;AKSELA, REIJO;PAREN, AARTO;RENVALL, ILKKA |
发明人 |
JAEKAERAE, JUKKA;AKSELA, REIJO;PAREN, AARTO;RENVALL, ILKKA |
分类号 |
D21C9/10;D21C9/14;D21C9/16;(IPC1-7):D21C9/16 |
主分类号 |
D21C9/10 |
代理机构 |
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代理人 |
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地址 |
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