Process for bleaching pulp
US8906199B2 · kind B2 · utility
3Cited by
3References
10Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Nov 3, 2008 |
| Grant date | Dec 9, 2014 |
| Priority date | — |
| Expiry date | Jun 6, 2029 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD21C9/163
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A process for the bleaching of wood pulp using one or more peroxide oxidising agents wherein the process includes treatment of the pulp with a mixture of chelating agents comprising: (a) a first chelating agent selected from the group consisting of: ethylenediamine N,N-disuccinic acid, methylglycinediacetic acid, glutamic acid N,N-diacetic acid, imino disuccinic acid and anions and mixtures thereof; and (b) a second chelating agent selected from the group consisting of: diethylene triamine pentaacetic acid, ethylenediamine tetraacetic acid, diethylenetriamine penta methylene phosphonic acid and anions and mixtures thereof.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.