Benzoate potassium

Aqueous solutions are slightly alkaline and have a sweetish astringent taste. 

Benzoate of potash benzoic acid potassium salt E212 kalium benzoat potassium salt trihydrate ProBenz PG. 

Potassium benzoate is predominantly used as an antimicrobial preservative in a wide range of beverages, foods and some pharmaceutical formulations. Preservative efficacy increases with decreasing pH it is most effective at pH 4.5 or below. However, at low pH undissociated benzoic acid may produce a slight though discernible taste in food products. 

Increasingly, potassium benzoate is used as an alternative to sodium benzoate in applications where a low sodium content is desirable. 

Therapeutically, potassium henzoate has also been used in the management of hypokalemia. See also Table I. 

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Dissolve 27 g. of potassium hydroxide in 25 ml. of water contained in a beaker or conical flask, and cool the solution to about 20° in ice water. Pour the solution into a 250 ml. reagent bottle, and add 30 g. (29 ml.) of pure benzaldehyde ("1) cork the bottle securely and shake the mixture vigorously until it has been converted into a thick emulsion. Allow the mixture to stand overnight or for 24 hours in the stoppered bottle. Add just sufficient water (about 105 ml.) to dissolve the potassium benzoate. Pour the liquid into a separatory funnel, rinse out the bottle with about 30 ml. of ether and add this ether to the solution in the funnel. Shake the... 

Mitsubishi Chemical Industries, Ltd. practiced a Henkel II technology starting with toluene to produce benzoic acid. Reaction of benzoic acid with potassium hydroxide resulted in potassium benzoate, which was subjected to a disproportionation reaction to produce dipotassium terephthalate and benzene. Dipotassium terephthalate reacted with sulfuric acid, and the resulting terephthahc acid was recovered by filtration and drying (65,66). Here, dipotassium sulfate was the by-product. 

The Henkel process employing potassium benzoate has been used in Japan for the manufacture of terephthaUc acid by the following scheme ... 

The growth of demand for benzoic acid is expected to increase at a rate of between 1 and 2% per year (17). Glycol dibenzoate plasticizers have been growing at close to 10% annually for the past several years, in part due to environmental concerns with regard to phthalate plasticizers (qv). The growth of the diet soft drink market has increased the demand for sodium and potassium benzoates (17). 

The largest use for benzoic acid is as a chemical raw material in the production of phenol, caprolactam, glycol dibenzoate esters, and sodium and/or potassium benzoate. 

Sodium and Potassium Benzoate. These salts are available in grades meeting the specifications of the 25ationalVormulary (18) and the Vood Chemicals Codex (19) (Table 7). Sodium benzoate [532-32-1] is produced by the neutralization of benzoic acid with caustic soda and/or soda ash. The resulting solution is then treated to remove trace impurities as weU as color bodies and then dried in steam heated double dmm dryers. The product removed from the dryers is light and fluffy and in order to reduce shipping and storage space the sodium benzoate is normally compacted. It is then milled and classified into various product forms, the names of which often bear Httle relationship to the actual form of the product. 

Potassium benzoate will be included in the Food Chemical Codex in the next supplement. Until such time potassium benzoate is sold as food-grade. Anhydrous basis. 

Potassium benzoate [582-25-2] is produced by neutralizing benzoic acid with caustic potash. The resulting solution is processed in a fashion nearly identical to that of sodium benzoate. Product forms are also similar. 

Sodium and potassium benzoate are employed in a wide range of preservative appHcations 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 appHcation areas where the pH is at 4.5 or lower (Table 8). 

Benzoic acid is suppHed to this market in the form of salts because the benzoate salts have a high solubiUty in water and aqueous stock solutions of up to 35% can easily be prepared. In addition, it is easier, and therefore cheaper, to purify sodium and potassium benzoate than to produce the USP/FCC grade of benzoic acid. 

Sodium and potassium benzoate are substances that may be added direcdy to human food and are affirmed as GRAS (33—35). Benzoic acid and sodium and potassium benzoate are now used as preservatives in such foods as sauces, pickles, cider, fmit juices, wine coolers, symps and concentrates, mincemeat and other acidic pie fillings, margarine, egg powder, fish (as a brine dip component), bottled carbonated beverages, and fmit preserves, jams, and jellies. The popularity of diet soft drinks has led to increased demand for both benzoate salts. 

Nonfood preservative appHcations 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). 

The use of the potassium salt of benzoic acid is relatively new. Concerns regarding sodium intake and its possible relationship to high blood pressure have caused some soft drink manufacturers to switch to potassium benzoate. 

Potassium hen ate [582-25-2], C H COOK, is even more soluble in water than sodium benzoate (73.6 g dissolve in 100 g of water at 25°C). A 25% aqueous solution of potassium benzoate exhibits a pH of 8—8.5. 

Prior to the commercial development of this process benzyl alcohol was obtained from benzaldehyde [100-52-7] which undergoes the Cannizzaro reaction (2) upon treatment with potassium hydroxide. High yields of benzyl alcohol and potassium benzoate are obtained by this route which cannot compete with the present day process because of the high cost of benzaldehyde (qv). 

Sodium or potassium benzoate at a concentration of 0.05% is a universally used preservative agent active against yeast and mold. At higher concentrations benzoate is also effective against bacteria. It is most effective at a pH between 2.0 and 4.0. Sodium or potassium sorbate inhibits the growth of yeast and mold and is most effective below pH 6.5. 

In 1909, Claisen described the first such reaction. Treating 2,5-di-methylisoxazolium methosulfate (140) with potassium benzoate in aqueous media he obtained the iV-methyl-iV-benzoyl amide (141) of acetoacetic acid. ... 

Terephthalic acid is an important monomer for producing polyesters. The main route for obtaining the acid is the catalyzed oxidation of paraxylene. It can also be produced from benzoic acid by a disproportionation reaction of potassium benzoate in the presence of carbon dioxide. Benzene is the coproduct ... 

Self-Tfst 10.14A Estimate the pH of 0.10 m KC6H5C02(aq), potassium benzoate see Table 10.1 for data. 

In a similar process, potassium benzoate heated with cadmium salts dispropor-tionates to benzene and 44. The term Henkel reaction (named for the company that... 

CgHjCHO + CsHjCHO — C.HsCHjOH + C.HjCOOK Benzaldehyde Benzyl alcohol Potassium benzoate... 

Similarly to classical PTC reaction conditions, under solid-liquid PTC conditions with use of microwaves the role of catalyst is very important. On several occasions it has been found that in the absence of a catalyst the reaction proceeds very slowly or not at all. The need to use a phase-transfer catalyst implies also the application of at least one liquid component (i.e. the electrophilic reagent or solvent). It has been shown [9] that ion-pair exchange between the catalyst and nucleophilic anions proceeds efficiently only in the presence of a liquid phase. During investigation of the formation of tetrabutylammonium benzoate from potassium benzoate and tetrabu-tylammonium bromide, and the thermal effects related to it under the action of microwave irradiation, it was shown that potassium benzoate did not absorb micro-waves significantly (Fig. 5.1, curves a and b). Even in the presence of tetrabutylammonium bromide (TBAB) the temperature increase for solid potassium benzoate... 

Henkel Also named Raecke, after the inventor. A process for making terephthalic acid from potassium benzoate by disproportionation ... 

Potassium salt trihydrate, C7H5K02. 3HzO, potassium benzoate. Cryst powder. Sol in water, ale. 

Potassium bases, 20 604-605 Potassium benzoate, 3 632t, 633-634, 635 Potassium P-alumina, 2 406t Potassium bicarbonate, 20 632 Potassium bifluoride, 11 838 Potassium borohydride, 13 615, 620 production process for, 13 617 Potassium bromate, 4 334-335 20 630 Potassium bromide, 20 630... 

Freshly distilled benzaldehyde (20 g.) is shaken in a stoppered cylinder or in a thick-walled flask with a cold aqueous solution of potassium hydroxide (18 g. in 12 g. of water) until a permanent emulsion is formed. The container is corked and left over night. To the crystalline paste (potassium benzoate) which separates, just sufficient water2 is added to enable the benzyl alcohol to be ex-... 

A series of imidate esters derived from secondary alcohols has been found to react with potassium benzoate or potassium phthalimide to give products of 5 n2 substitution in excellent yields and with clean inversion of stereochemistry. ... 

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