Bleach boosting

Enzymes in Pulp and Paper Production. Enzyme-modified starch has been used for adhesives to strengthen paper base and for surface coating. Developments since the late 1980s of further uses of enzymes in papermaking include pitch control and bleach boosting, (see Paper Pulp). 

L. S. Pederson, On EseofPulpgymeHA for Bleach Boosting Novo Nordisk A/S, Bagsvaerd, Denmark, Sept. 1989. 

Blattellaquinone, 27 259 Bleach activator, ethyleneamines application, 8 500t, 504-505 Bleach boosting, 70 304-305 Bleached board products, 78 130 Bleached chemo-thermo mechanical pulp (BCTMP), 74 57 Bleached montan wax, 9 677 Bleaches. See also Bleaching... 

Until recently, the use of enzymes in the paper and pulp industry was not cortsidered technically or economically feasible. Quite simply, suitable enzymes were not readily available, except for the limited use of enzymes to modify starch for paper coatings. However, research by scientific institutions and enzyme producers has led to the development of new enzymes that offer significant benefits for the industry, particrrlarly from the environmental point of view. Two examples of applications, in addition to the starch modification, made possible by new enzyme developments are given here bleach boosting and pitch control. 

Bleach boosting (lignin removal) paper pulp through hemiceUulose hydrolysis Xylanase... 

Lin XQ, Han SY, Zhang N, Hu H, Zheng SP, Ye YR, Lin Y. (2013). Bleach boosting effect of xylanase A from Bacillus halodurans C-125 in ECE bleaching of wheat straw pulp. Enzyme Microb Technol, 52, 91-98. 

Scheper, W. M., Sivik, M. R., Perkins, C. M. et al.. Bleach boosting catalyst for use in automatic dish-wash detergents, HAPPI (October) 58-68, 1998. 

Starch-coating, de-inking, drainage Bleach boosting... 

It is sometimes possible to add properties in Hquid formulations that provide additional functions. Examples in development or in commercial use as of 1993 include microencapsulation (qv) of enzymes for protection against bleach when dispersed in a Hquid detergent addition of certain polymers to protect the enzyme after it has been added to Hquid detergents (32), or to boost activity in the final appHcation addition of surfactants or wetting agents. 

Sodium carbonate peroxide breaks down into sodium carbonate and hydrogen peroxide. The hydrogen peroxide acts as a bleach and as an antimicrobial agent. The high alkalinity of the sodium carbonate boosts the bleaching effect of hydrogen peroxide. 

Since common bleach activators lack reactivity below 40°C, several attempts have been made to boost their performance by adding on catalyticaUy acting molecules. In the 1980s, the use of sodium bromide [175] was recommended, which then forms hypobromite in the wash process—an effective but not environmentally friendly compromise. 

The efficiency of defibrillation in the ultrasonic process is dependent on power, concentration, temperature, size of fibers, time and distance from probe tip to collector [77]. In some cases, researchers have been used a combination of ultrasonication with other methods to increase fibrillation of nanoscale cellulose. For example, Li et al. [78] prepared nanocrystalline cellulose by ultrasonication and acid hydrolysis with H SO from bleached softwood pulp. They found that ultrasonication led to folding and erosion of the cellulose surface, and thus provided more reactive site to penetrate acid and prepare high-crystalline and small-size nanocellulose. Furthermore, Wang and Chen [77] reported that a combination of ultrasonication and homogenization boosts uniformity and fibrillation of cellulose nanofiber in comparison to ultrasonication solely. In addition, when compared to mechanical blender, ultrasonic bath and ultrasonic probe, Mishra et al. [79] concluded that TEMPO-oxidized fiber treatment with ultrasonic probe was more efficient for nanocellulose production than the other three methods. 

In some coimtries, it is the practice for the bleach to be added separately from the detergent formulation, either to provide bleach action for formulations that do not contain a coformulated bleach dr to boost flie performance of those that already do. Such dry bleaches or bleach boosters contain typically 10-15% TAED and 35-50% sodium perborate. 

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