Paper making and fiber liberation – Processes of chemical liberation – recovery or purification... – Gas – vapor or mist contact
Reexamination Certificate
2011-07-12
2011-07-12
Daniels, Matthew J (Department: 1741)
Paper making and fiber liberation
Processes of chemical liberation, recovery or purification...
Gas, vapor or mist contact
C162S009000, C162S074000
Reexamination Certificate
active
07976677
ABSTRACT:
This invention relates to an improved bleaching process for bleaching pulp comprising at least one bleaching stage which comprises treating a hardwood pulp with a bleaching agent comprising ClO2in the presence of a weak base such as, for example, Mg(OH)2preferably at pH from about 3.5 to about 6.5. The invention is also relates a bleaching process for bleaching pulp having two or more bleaching stages, at least one of which and preferably two of which comprises treating a hardwood pulp with a bleaching agent comprising ClO2in the presence of a weak base such as, for example, Mg(OH)2preferably at pH from about 3.5 to about 6.5.
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Witherspoon Kent
Yin Caifang
Barnes, III Thomas W.
Calandra Anthony J
Daniels Matthew J
Eslami Matthew M.
Guttag Eric W.
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