Processes for pulping raw pulp material, such as wood chips, to provide pulp fibers having increased bulk, as well as bleaching the resulting pulp fibers to provide bleached pulp fibers having increased bulk. These pulp fibers and bleached pulp fibers may be incorporated into or used various products, such as multi-ply coated paperboards, fluff pulp, etc.

A method of producing bleached microcrystalline cellulose which method comprises neutralizing or alkalizing an acidic microcrystalline production reaction mixture slurry, typically produced by acid hydrolysis or by electronic beam irradiation, followed by adding an oxidant to such reaction mixture. This practice of this method permits the production of microcrystalline cellulose having desirable color stability as well as compression characteristics suitable for pharmaceutical binder use from paper grade and other low purity pulps.

An omnibus process of pulping and bleaching lignocellulosic materials in which a charge of a lignocellulosic material is biopulped and/or water extracted prior to pulping and bleaching. The lignocellulosic material may be mechanically pulped and bleached in the presence of an enzyme that breaks lignin-carbohydrate complexes.

An omnibus process of pulping and bleaching lignocellulosic materials in which a charge of a lignocellulosic material is biopulped and/or water extracted prior to pulping and bleaching. The lignocellulosic material may be mechanically pulped and bleached in the presence of an enzyme that breaks lignin-carbohydrate complexes.

A surfactant treated bleached softwood kraft pulp fiber, useful as a starting material in the production of cellulose derivatives including cellulose ether, cellulose esters and viscose, is disclosed. Methods for making the kraft pulp fiber and products made from it are also described.

An omnibus process of pulping and bleaching lignocellulosic materials in which a charge of a lignocellulosic material is biopulped and/or water extracted prior to pulping and bleaching. The lignocellulosic material may be mechanically pulped and bleached in the presence of an enzyme that breaks lignin-carbohydrate complexes.

A surfactant treated bleached softwood kraft pulp fiber, useful as a starting material In the production of cellulose derivatives including cellulose ether, cellulose esters and viscose, is disclosed. Methods for making the kraft pulp fiber and products made from it are also described.

Recycle fiber bleaching includes an oxygen pre-treatment to activate the fiber for further bleaching. A preferred method of making a high brightness papermaking pulp from recycled cellulose fiber includes: (a) pre-treating a first recycled cellulosic fiber mix with oxygen, said first recycled cellulosic fiber mix having a first high Kappa number prior to pre-treatment and a reduced Kappa number after pre-treatment that is lower than said first high Kappa number; and (b) blending the pre-treated first recycled cellulosic fiber mix with the reduced Kappa number with a second recycled cellulosic fiber mix having a second Kappa number lower than the first high Kappa number of the first recycled cellulosic fiber mix; and (c) oxidatively bleaching the blended recycled cellulosic fiber mix of step (b); and optionally (d) reductively bleaching the blended recycled cellulosic fiber mix of step (c).

In a process/an apparatus for producing bleached cellulose in which a lignin- and cellulose-containing suspension is subjected to at least one process step for oxygen-assisted bleaching in a reactor, such as alkaline oxygen delignification, oxygen-enhanced extraction or oxygen-enhanced peroxide bleaching, the oxygen required for the oxygen-assisted bleaching is supplied to the reactor at least partially in the form of oxygen-containing nanobubbles. The small size and high stability of the nanobubbles allow uniform distribution of the oxygen in the suspension and a comparatively long exposure time. The efficiency of the bleaching is thus substantially increased.