Synthesis
 From toluene in the presence of cobalt naphthenate catalyst to take pre-emptive air oxidation of benzoic acid, then acid as raw materials, each with sodium bicarbonate, active carbon, then the results of filtration, drying, crushing the product were.

 Quality standards
 The national standard GB 1902-94 with reference to the provisions of the quality indicators of sodium benzoate,

 Benzoic acid and sodium benzoate
 At present, China mainly uses food preservative sodium benzoate and potassium sorbate, sodium benzoate as cheap, widely used by food companies.

 Physical and chemical properties (Wan Su-Ying, 1998; Ling Guan Ting, 2003):

 Benzoic acid
 (Benzoic Acid)

 Molecular formula: C6H5COOH

 Also known as benzoic acid, benzoin odorless or slight odor, widely used as a food preservative, found naturally in cranberries, prunes, cinnamon, cloves, is an aromatic acid, can also be added as a spice. Acid dissociation has no antibacterial activity, the PH value 2.5-4.0 range, was the best activity. Toxicological basis: LD oral rat 2530mg. kg-1 (bw) 50GRAS FDA-21CFR 184.1021ADI 0-5mg. kg-1 (bw) (the total amount of formic acid and its salts, benzoic acid count) (FAO / WHO, 1994)