Preservatives applications

Sodium and potassium benzoate are employed in a wide range of preservative applications because they provide an effective combination of antimicrobial action, low cost, and safety. Although sodium and potassium benzoate are the preservatives offered in the marketplace, the actual active ingredient being sold is free (or undissociated) benzoic acid. The benzoate ion has essentially no antimicrobial properties. Since it is the undissociated (free) benzoic acid that provides the antimicrobial action, sodium benzoate and potassium benzoate are recommended for use in application areas where the pH is at 4.5 or lower (Table 8). 

Nonfood preservative applications of sodium and potassium benzoate are found in pharmaceutical and cosmetic preparations, such as toothpastes and powders, tobacco, pastes and glue, as well as starch and latex (36,37). 

In terms of paper conservation, this work is of value since it is an attempt to determine (i) if UV and EB grafting times for cellulose copolymerization can be shortened significantly by the inclusion of appropriate additives and (ii) if such a process is capable of incorporating into cellulose properties required for preservation, particularly wet and dry strength and flexibility. These studies also should indicate the feasibility of extrapolating data from the present solvent grafting systems to processes based on solvent-free, rapid-cure UV and electron beam (EB) which are the ideal polymerization conditions for preservation applications. 

A number of fatty amines and their derivatives, especially quaternary ammonium compounds, are widely used in formulations for the control of bacteria, fungi, viruses and algae, in disinfectant/sanitizers and wood-preservation applications. Table 14.3 presents the fatty amines and derivatives which are frequently used in biocidal formulations. 

General information. Bronopol is a halogenated diol that also contains an electrophilic carbon atom. It is used extensively in water treatment applications and, like DBNPA (see 5.4.3.), has seen limited applications in the oilfield. It is used primarily in fluid preservation applications, most notable in the preservation of fracturing fluids or other fluids that are neutral to slightly basic in pH. Bronopol is particularly effective against Pseudomonas bacteria. 

General information. Glutaraldehyde is a 5-carbon dialdehyde that has seen extensive use in industrial water treatment applications. In addition to its use as a biocide in oil and gas operations, it is also used in cooling water, paper making, and preservative applications, medical instrument sterilization, and as a non-biocidal crosslinker for leather. X-ray films, and enzyme immobilization. It is often used in oilfield applications in combination with other non-oxidizing biocides such as QAC s and formaldehyde and is compatible with the oxidizing biocides typically used in cooling water applications. 

Active substance Film preservative application Dosage % based on paint Further appUcation Typical dosage % in further applic. 

As is shown by the MIC in Table 88., dithio-2,2 -bis(benzmethylamide) s spectrum of effectiveness covers in particular fungi, but yeasts and bacteria, too. This and the solubility properties of the microbicide make it suitable for anti-fungal protection of dry films (paints, adhesives, sealants) and for wet state preservation applications. The addition rates of a formulation containing 25% a. i. move between 0.05-0.20% for the in-can/in-tank preservation of aqueous products and 0.5-2.0% for dry film applications. The agent is active over pH range 4-12. 

National Historic 1 Requires action to preserve Applicable to property Cultural Survey to determine if 2... 

Adhesive properties sometimes have a decisive effect on the choice of methods and conditions for the preparation, preservation, application, and transportation for powdered materials. These properties must never be neglected when constructing and preparing the working parts of mechanisms intended for working with powders. 

Beyond the traditional uses and the recently renewed capacity to repair natural cement buildings and stmctures in kind, natural cement holds great promise as a specialty material for use in a variety of restoration and preservation applications. They promise to be a resource that will remain in good supply, as well. Unlike the exhausted or inaccessible sources elsewhere, the mines in Rosendale, New York, still... 

This makes MITROL PQ-56 a product of choice for preservative application where environmental safety is of prime importance. 

Latest technological developments have yielded a full line of Registered M-GARD products designed to replace pentachloro-phenol and creosote for various wood preservative applications. 

Benzaldehyde is easily oxidised by atmospheric oxygon giving, ultimately, benzoic acid. This auto-oxidation is considerably influenced by catalysts tiiose are considered to react with the unstable peroxide complexes which are the initial products of the oxidation. Catalysts which inhibit or retard auto-oxidation are termed anti-oxidants, and those that accelerate auto-oxidation are called pro-oxidants. Anti-oxidants find important applications in preserving many organic compounds, e.g., acrolein. For benzaldehyde, hydroquinone or catechol (considerably loss than U-1 per cent, is sufficient) are excellent anti-oxidants. 

Enzymes not only produce characteristic and desirable flavor (79) but also cause flavor deterioration (80,81) (see Enzyme Applications, Industrial). The latter enzyme types must be inactivated in order to stabilize and preserve a food. Freezing depresses enzymatic action. A more complete elimination of enzymatic action is accompHshed by pasteurization. 

Miscellaneous Applications. CeUular plastics have been used for display and novelty pieces from their eady development. Polystyrene foam combines ease of fabrication with lightweight, attractive appearance, and low cost to make it a favorite in these uses. PhenoHc foam has its principal use in doral displays. Its abiHty to hold large amounts of water for extended periods is used to preserve cut dowers. CeUular poly(vinyl chloride) is used in toys and athletic goods, where its toughness and ease of fabrication into intricate shapes have been valuable. 

NHydroxyben2oic acid is of significant commercial importance. The most familiar application is the use of several of its esters as preservatives, known as parabens. Also of interest is the use in liquid crystal polymer applications. 

U.S. EPA, Membrane Treatment ofWood Preserving Site Groundwater by SBP Technologies, Inc., Applications Analysis Report, EPA/540/AR-92/014, Washington, D.C., 1993. 

Start agitator. Add preservatives if applicable, and mix until dissolved. 

Hexamethyleneimine, N-nitroso-synthesis, 7, 518 Hexamethylenetetramine applications, 3, 529 degradative nitrosation, 3, 488 food preservative, 1, 411 quatemization, 3, 488 reactivity, 3, 487 88 structure, 2, 6 synthesis, 3, 509... 

Vertical Pressure Leaf Filters are essentially the same as Horizontal Plate Filters except for the orientation of the filter elements which are vertical rather than horizontal. They are applied for the polishing slurries with very lov solids content of 1-5% or for cake filtration with a solids concentration of 20-25%. As with the horizontal plate filter the vertical leaf filters are also well suited for handling flammable, toxic and corrosive materials since they are autoclaved and designed for hazardous environments when high pressure and safe operation are required. Likewise, they may be readily jacketed for applications whenever hot or cold temperatures are to be preserved.The largest leaf filters in horizontal vessels have a filtration area of 300 m and vertical vessels 100 m both designed for an operating pressure of 6 bar. 

The odor control market is the largest and much of this market is in sewage treatment plants. Use of ozone for odor control is comparatively simple and efficient. The application is for preservation of environmental quality in addition, alternative treatment schemes requiring either liquid chemical oxidants (like permanganate or hydrogen perioxide) or incineration can significantly increase capital and costs. 

A platform was being constructed from one storage tank to another, without the workers knowing that mixture of benzoic acid and air in the open storage tank could explode. DSM is the largest European producer of benzoic acid which is used in a range of applications from a pla.sttcizcf to food preservative. DSM s capacity here is 440 million lb per year. 

---