Bleaching of deinked paper/wood pulp

Paper making and fiber liberation – Processes of chemical liberation – recovery or purification... – Waste paper or textile waste

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

162 7, 162 78, 162 84, D21C 910, D21C 916

Patent

active

054494362

ABSTRACT:
Deinked paper/wood pulps are improvedly bleached to high levels of whiteness by conjointly treating such pulps with a sulfite bleaching agent, e.g., Na.sub.2 SO.sub.3, NaHSO.sub.3 or mixture thereof, or SO.sub.2 and NaOH, and a reducing agent more electronegative than the sulfite ion, e.g., thiourea dioxide, sodium borohydride or sodium dithionite, in a reaction medium having an initial pH ranging from 6 to 12, advantageously followed by washing sulfite and reducing agent values from the bleached pulp and then treating the washed pulp with hydrogen peroxide in an aqueous alkaline medium.

REFERENCES:
patent: 3384534 (1968-05-01), Kindron et al.
patent: 3981765 (1976-09-01), Kruger et al.
patent: 3985674 (1976-10-01), Ellis et al.
patent: 4812206 (1989-03-01), Devic et al.
patent: 5143581 (1992-09-01), Devic

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Bleaching of deinked paper/wood pulp does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Bleaching of deinked paper/wood pulp, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Bleaching of deinked paper/wood pulp will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-403762

All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.