D21C9/147

Oxygen Treatment of High Kappa Fibers

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).

Methods of pulp fiber treatment

In some embodiments, a method may include treating pulp in pulp and paper mills. The methods may include providing a peracetate oxidant solution and generating a reactive oxygen species. The peracetate solution may include peracetate anions and a peracid. In some embodiments, the peracetate solution may include a pH from about pH 10 to about pH 12. In some embodiments, the peracetate solution has a molar ratio of peracetate anions to peracid ranging from about 60:1 to about 6000:1. In some embodiments, the peracetate solution has a molar ratio of peracetate to hydrogen peroxide of greater than about 16:1. The peracetate oxidant solution may provide enhanced treatment methods of bleaching, brightening, and delignifying pulp fibers involving the use of peracetate oxidant solutions.

BLEACHING AND SHIVE REDUCTION PROCESS FOR NON-WOOD FIBERS
20210032812 · 2021-02-04 ·

The present invention is directed to a method of increasing the brightness of non-wood fibers and nonwoven fabric fabrics produced by the method. In one aspect, the method includes forming a mixture of non-wood fibers and exposing the mixture to a brightening agent to produce brightened fibers. The brightening agent is oxygen gas, peracetic acid, a peroxide compound, or a combination thereof. The brightened fibers have a brightness greater than the fibers of the mixture before exposure as measured by MacBeth UV-C standard.

BLEACHING AND SHIVE REDUCTION PROCESS FOR NON-WOOD FIBERS
20210032812 · 2021-02-04 ·

The present invention is directed to a method of increasing the brightness of non-wood fibers and nonwoven fabric fabrics produced by the method. In one aspect, the method includes forming a mixture of non-wood fibers and exposing the mixture to a brightening agent to produce brightened fibers. The brightening agent is oxygen gas, peracetic acid, a peroxide compound, or a combination thereof. The brightened fibers have a brightness greater than the fibers of the mixture before exposure as measured by MacBeth UV-C standard.

BLEACHING AND SHIVE REDUCTION FOR NON-WOOD FIBERS
20210032801 · 2021-02-04 ·

The present invention is directed to a method of increasing the brightness of non-wood fibers and nonwoven fabric fabrics produced by the method. In one aspect, the method includes forming a mixture of non-wood fibers and exposing the mixture to a brightening agent to produce brightened fibers. The brightening agent is oxygen gas, peracetic acid, a peroxide compound, or a combination thereof. The brightened fibers have a brightness greater than the fibers of the mixture before exposure as measured by MacBeth UV-C standard.

Methods of pulp fiber treatment
10883224 · 2021-01-05 · ·

In some embodiments, a method may include treating pulp. The method may include contacting a wood pulp with a singlet oxygen source. The method may include contacting the wood pulp with an alkaline peroxide source. The singlet oxygen source may include a peracetate oxidant solution and generating a reactive oxygen species. The peracetate oxidant solution may include peracetate anions and a peracid. In some embodiments, the peracetate solution may include a pH from about pH 10 to about pH 12. In some embodiments, the peracetate solution has a molar ratio of peracetate anions to peracid ranging from about 60:1 to about 6000:1. In some embodiments, the peracetate solution has a molar ratio of peracetate to hydrogen peroxide of greater than about 16:1. The peracetate oxidant solution may provide enhanced treatment methods of bleaching, brightening, and delignifying pulp fibers involving the use of peracetate oxidant solutions.

Methods of pulp fiber treatment
10883224 · 2021-01-05 · ·

In some embodiments, a method may include treating pulp. The method may include contacting a wood pulp with a singlet oxygen source. The method may include contacting the wood pulp with an alkaline peroxide source. The singlet oxygen source may include a peracetate oxidant solution and generating a reactive oxygen species. The peracetate oxidant solution may include peracetate anions and a peracid. In some embodiments, the peracetate solution may include a pH from about pH 10 to about pH 12. In some embodiments, the peracetate solution has a molar ratio of peracetate anions to peracid ranging from about 60:1 to about 6000:1. In some embodiments, the peracetate solution has a molar ratio of peracetate to hydrogen peroxide of greater than about 16:1. The peracetate oxidant solution may provide enhanced treatment methods of bleaching, brightening, and delignifying pulp fibers involving the use of peracetate oxidant solutions.

Bleaching and shive reduction process for non-wood fibers
10844538 · 2020-11-24 · ·

The present invention is directed to a method of increasing the brightness of non-wood fibers and nonwoven fabric fabrics produced by the method. In one aspect, the method includes forming a mixture of non-wood fibers and exposing the mixture to a brightening agent to produce brightened fibers. The brightening agent is oxygen gas, peracetic acid, a peroxide compound, or a combination thereof. The brightened fibers have a brightness greater than the fibers of the mixture before exposure as measured by MacBeth UV-C standard.

Bleaching and shive reduction process for non-wood fibers
10844538 · 2020-11-24 · ·

The present invention is directed to a method of increasing the brightness of non-wood fibers and nonwoven fabric fabrics produced by the method. In one aspect, the method includes forming a mixture of non-wood fibers and exposing the mixture to a brightening agent to produce brightened fibers. The brightening agent is oxygen gas, peracetic acid, a peroxide compound, or a combination thereof. The brightened fibers have a brightness greater than the fibers of the mixture before exposure as measured by MacBeth UV-C standard.

Crosslinked cellulose as precursor in production of high-grade cellulose derivatives and related technology
10829892 · 2020-11-10 · ·

A pulp in accordance with a particular embodiment includes crosslinked cellulose fibers. The pulp can have high brightness, reactivity, and intrinsic viscosity. The pulp, therefore, can be well suited for use as a precursor in the production of low-color, high-viscosity cellulose derivatives. A method in accordance with a particular embodiment of the present technology includes forming a pulp from a cellulosic feedstock, bleaching the pulp, crosslinking cellulose fibers within the pulp while the pulp has a high consistency, and drying the pulp. The bleaching process can reduce a lignin content of the pulp to less than or equal to 0.09% by oven-dried weight of the crosslinked cellulose fibers. Crosslinking the cellulose fibers can include exposing the cellulose fibers to a glycidyl ether crosslinker having two or more glycidyl groups and a molecular weight per epoxide within a range from 140 to 175.