Liquid activators, bleaches

In addition to soln. of chloride of lime—lime bleach liquor—bleaching liquids with magnesium, zinc, or aluminium hypochlorites as the active agents have also been made and special virtues claimed for their use. For example, if magnesium sulphate be added to a soln. of bleaching powder, calcium sulphate is precipitated and a soln.—magnesia bleach liquor—of magnesium hypochlorite can be decanted off similarly with zinc hypochlorite—zinc bleach liquor and with aluminium hypochlorite—alumina bleach liquor, or Wilson s bleach liquor. 

In an aqueous solution, NaClO does not exist as a complete rmit, but as sodium ions, Na+, and hypochlorite ions, CIO". The ingredient responsible for the bleaching action in this type of bleach is the hypochlorite ion. Many other solid and liquid bleaches contain hydrogen peroxide, H2O2, instead of sodium hypochlorite. In these bleaches, the active substance in solution is the perhydroxyl ion, HOO. What do the CIO and HOO" ions have in common ... 

Liquid activators are preferred in industrial applications, because they are easy to dose via pumps and dissolve more quickly in the bleaching bath than solid activators. Besides MOR, acetyl caprolactam (ACL) [31] (Figure 16.10) can also be used for this purpose. 

Sodium hypochlorite [II, 21.2.2d. Sodium hypochlorite is a clear, slightly yellow liquid aqueous. Household bleach has active concentrations between 5.25 and 6.00% whereas concentrations of 5 to 15% are used in the industry. Most commercial applications use the more concentrated solutions. One gallon of sodium hypochlorite yields approximately the same quantity of active chlorine as one pound of chlorine gas. 

The seasoning is subsequently stored it is filtered several times before filling. Apart from liquid food seasoning, seasoning in paste and powder form and mixtures for use in dry soups and sauces are produced. These products are partly bleached with activated carbon and the taste is neutralized. 

Filter aids may be applied in one of two ways. The first method involves the use of a precoat filter aid, which can be applied as a thin layer over the filter before the suspension is pumped to the apparatus. A precoat prevents fine suspension particles from becoming so entangled in the filter medium that its resistance becomes exces-sive. In addition it facilitates the removal of filter cake at the end of the filtration cycle. The second application method involves incorporation of a certain amount of the material with the suspension before introducing it to the filter. The addition of filter aids increases the porosity of the sludge, decreases its compressibility, and reduces the resistance of the cake. In some cases the filter aid displays an adsorption action, which results in particle separation of sizes down to 0.1 /i. The adsorption ability of certain filter aids, such as bleached earth and activated charcoals, is manifest by a decoloring of the suspension s liquid phase. This practice is widely used for treating fats and oils. The properties of these additives are determined by the characteristics... 

The H2O2 used as substrate is generated by the NADPH oxidase system. CT is the halide usually employed, since it is present in relatively high concentration in plasma and body fluids. HOCI, the active ingredient of household liquid bleach, is a powerful oxidant and is highly microbicidal. When applied to normal tissues, its potential for causing damage is diminished be-... 

The term three-phase fluidization, in this chapter, is taken as a system consisting of a gas, liquid, and solid phase, wherein the solid phase is in a non-stationary state, and includes three-phase slurry bubble columns, three-phase fluidized beds, and three-phase flotation columns, but excludes three-phase fixed bed systems. The individual phases in three-phase fluidization systems can be reactants, products, catalysts, or inert. For example, in the hydrotreating of light gas oils, the solid phase is catalyst, and the liquid and gas phases are either reactants or products in the bleaching of paper pulp, the solid phase is both reactant and product, and the gas phase is a reactant while the liquid phase is inert in anaerobic fermentation, the gas phase results from the biological activity, the liquid phase is product, and the solid is either a biological carrier or the microorganism itself. 

It is sometimes possible to add properties in liquid 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 liquid detergent addition of certain polymers to protect the enzyme after it has been added to liquid deteigents (32), or to boost activity in the final application addition of surfactants or wetting agents,... 

Bleach (sodium hypochlorite) 1 lb liquid bleach, NaOCl, typically contains 12.5% active chemical and 87.5% inactives. 1 lb of liquid bleach provides 0.088 lb HOCI. 

For host/guest systems, tri(acryloxyethyl)trimelletate (7), a liquid trifunctional monomer was employed. This compound is easily and rapidly crosslinked to a tough solid by photopolymerization in the presence of a suitable sensitizer and activator, for example 8 and 9. This particular initiator system is useful because the sensitizer 8 is partially bleached out during irradiation, which allows the light to penetrate the sample as polymerization proceeds. 

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