Ácido benzóico

O ácido benzóico é um composto orgânico aromático cristalino, incolor ou branco, com odor característico e ligeiramente balsâmico, apresentando ponto de fusão em torno de 122 °C e baixa volatilidade à temperatura ambiente. Classificado como um ácido carboxílico aromático, é obtido principalmente pela oxidação parcial do tolueno ou por hidrólise de benzonitrila. Industrialmente, atua como importante intermediário químico na síntese de ésteres benzóicos, benzoatos de sódio e potássio, além de derivados utilizados em fragrâncias, conservantes alimentares e agentes de cura para polímeros. Suas principais aplicações concentram-se nos setores de alimentos (como conservante), farmacêuticos (na formulação de fármacos tópicos e excipientes), cosméticos (em produtos de higiene pessoal) e indústria de plásticos (como precursor de plastificantes e estabilizadores).

1. Used as a chemical reagent and preservative.2. Benzoic acid is important type food preservative. Under acidic conditions, It has inhibitory effects to mold, yeast and bacteria , but the effect is weak acid producing bacteria. The most appropriate antimicrobial pH values is ranging from 2.5 to 4, generally lower, the pH value is appropriate from 4.5 to 5. In the food industry with plastic barrels concentrated fruit and vegetable juice, the maximum use amount shall not be over 2.0g/kg; in jam (excluding canned), (taste) juice drink, soy sauce, vinegar in the maximum dose of 1.0g/kg; in soft candy, wine, wine in the maximum dose of 0.8 g/kg separately; in the low salt pickled vegetables, the sauce, candied fruit, maximum dose is 0.5 g/kg; in carbonated drinks in the largest amount of use is 0.2g/kg. due to benzoic acid, slightly soluble in water, its use can be a small amount of ethanol enable dissolved. 3.Preservative; anti microbial agents.Due to the low solubility of benzoic acid and use shall be stirring, or dissolved in a small amount of hot water or ethanol. When used in the soft drink with fruit juice concentrate, for benzoic acid easy volatile with the water vapor, so often used in the sodium salt, besides the above sodium equivalent to benzoic acid 0.847g.4.Often used as a fixative agent or preservative. Also used as a fruit juice aroma conservation agents. As a perfume with perfume fragrance. Can also be used for chocolate, lemon, orange, berries, nuts, candied fruit type edible essence. Tobacco flavor is also commonly used.5.Benzoic acid and its sodium salt are food preservatives. Under acidic conditions, it has inhibition of yeasts and molds. When pH 3, antibacterial strength and when pH 6, many fungi effect is very poor, so the antibacterial optimum pH is 2.5-4.0. Benzoic acid is mainly used for the production of sodium benzoate preservatives, dyes intermediates, pesticides, plasticizers, mordant, medicine, spice and also can be used as alkyd resin and polyamide resin modifier for the production of polyester, terephthalic acid and used equipment, iron and steel anti rust agent.6.Mainly used for antifungal and antiseptic.7.Used in medicine, dye carriers, plasticizer, spices and food preservatives such as production, and can also be used to paint of alkyd resin performance improvement; used as pharmaceutical and dye intermediates, used for the preparation of plasticizer and spices etc., as well as equipment, iron and steel anti rust agent.
Scaly or needle like crystals. With the smell of formaldehyde or benzene. Slightly soluble in water, soluble in ethanol, methanol, diethyl ether, chloroform, benzene, toluene, CS2, CCl4 and turpentine.