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).

The application relates to a method for preparing dissolving pulp by totally chlorine-free bleaching of poplar kraft pulp, including: preparing poplar kraft pulp by pre-hydrolysis kraft process with poplar as raw material; ZOQP bleaching of poplar kraft pulp to obtain dissolving pulp, wherein Z denotes ozone bleaching, O denotes oxy delignification, Q denotes chelation treatment, and P denotes hydrogen peroxide bleaching. In this way, washing and bleaching wastewater can be recycled in entire preparation process described above, achieving zero discharge. The dissolving pulp prepared by the method has no residual toxic substances, and exhibits that all indexes exceed the requirements of qualified products in dissolving pulp industry standard (QB/T 4898-2015), and most of indexes meet those of excellent products; thus, it can replace imported dissolving pulp. The use of the method significantly solved the problems of large pollution in the production and shortage of raw materials for viscose fibers.

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.

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.

The present application discloses an alternative method for selective removal of K.sup.+ and Cl.sup. from recovery boiler electrostatic precipitator ashes in a kraft-pulp process through the use of pure or impure CO.sub.2, complemented or not with a mineral acid, for instance Sulfuric Acid/Spent Acid.

A bleached softwood kraft pulp fiber with high ?-cellulose content and a low CED viscosity is provided, A surfactant treated fiber useful in the production of chemical derivatives is also described. Methods for making the kraft pulp fiber and products made from it are also described.

A pulp fiber with an enhanced carbonyl content resulting in improved antimicrobial, anti-yellowing and absorptive properties. Methods for making the kraft pulp fiber and products made from it are also described.

The invention provides a method for the application of a bleaching agent to a substrate, the method comprising the treatment of the substrate in an aqueous system comprising a liquid bleaching agent in a closed container, the treatment being carried out at a ratio of liquor to substrate which does not exceed 3:1. Typically, the method is applied to the bleaching of textile fibres and may optionally comprise a bleaching and scouring treatment. The invention also provides a method for the removal of surplus bleaching agents following the bleaching treatment, the method comprising not more than three aqueous wash-off treatments of the substrate. In addition to facilitating the use of much reduced liquor levels, the method also allows for significant reductions to be achieved in usage levels of bleaching agents, auxiliary agents and rinsing agents, thereby reducing generation of waste liquors requiring disposal. Furthermore, treatment temperatures are also significantly lower than for prior art methods, providing yet further benefits in environmental and cost terms.

The present invention relates to compositions for use in an aqueous pulp bleaching process, comprising one or more alkaline earth metal oxides and/or one or more alkaline earth metal hydroxides; one or more alkaline earth metal salts; and optionally, one or more pitch control additives. Methods and kits for the formation of said compositions, are also part of the invention, as is the use of said compositions, methods and kits.

The present disclosure provides a cigarette wrapper including a nanocellulose film, a smoking article comprising the same, and a method for manufacturing the cigarette wrapper including a nanocellulose film.

Through this, there is an advantage in that it is possible to minimize the generation of paper smell and steaming smell of paper-type cigarette paper used in the past, to reduce the smoker's displeasure, and to further improve the satisfaction of smoking.