【正文】 for archival filing certification, enterprises sold every batch of goods to perform detailed registration, and to the public security an for the record. According to the legal provisions, to undocumented units 200 kg acetic anhydride, will be sentenced to 3 years imprisonment. Industrialization of acetic anhydride production process has three kinds: the oxidation of acetaldehyde, ethylene ketone and methyl acetate carbonylation. Acetaldehyde oxidation technology source for the Canadian Sha Winigan chemical pany. The production process is as follows: acetaldehyde and oxygen at 60 degrees C, 101 kPa or 70 degrees C, 600700kPa under the conditions of the oxidation reaction, oxygen or air as the oxidant, using ethyl acetate as solvent, cobalt acetate as catalyst, acetic acid copper as promoter. Acetaldehyde and oxygen ( in excess of about 1%2%) reaction is first generated peroxy acetic acid, acetic acid and acetaldehyde reaction of acetic anhydride and acetic acid. Under this 1 condition, the conversion rate of acetaldehyde acetic anhydride and acetic acid production rate is 95%, the mass ratio of 56: 44. The total yield of 70%75% acetic anhydride. By changing the processing conditions, can improve the yield of acetic anhydride. Reaction equation: CH3CHO+O2 CH3COOOH。Acetic anhydride production process Acetic anhydride is a colorless volatile, with a strong irritating smell and corrosiveness liquid. Name of acetic anhydride, molecular formula C4H6O3, the flash point of DEG c.. Density of 0g / cm3. Melting point DEG c.. The boiling point of DEG c.. The refractive index nD . 20 degrees of viscosity of mPa? S. Spontaneous ignition temperature of DEG c.. Soluble in cold water, in water is deposed into acetic acid, ethyl acetate and ethanol production. Soluble in chloroform, ether and benzene. Toxic, eye and mucosa has a strong irritating, mass concentration of mg / m3 when the eye irritation。 / m3, can change a person39。 CH3COOOH+CH3CHO CH3COOOCH ( OH ) CH3 ( single peroxy acetic ester )。 CH3COOOCH ( OH CH3 2CH3COOH ). Acetaldehyde acetic anhydride consumption per ton of T, 2300 m3 standard air. Acetaldehyde oxidation method has the advantages of simple process, technology is mature, but the serious corrosion, high consumption, has gradually been eliminated. In foreign countries have been carbonylation of methyl acetate and vinyl ketone method alternative. China Shanghai Chemical Reagent Factory of this device has been in a state of production. Vinyl ketone law in accordance with the different materials can be divided into: acetic acid and acetone method. Acetic acid process technology from Germany Wacher chemical pany. The production process is as follows: in the first step, the acetic acid in 700750 C, 1020kPa pressure and %% phosphoric acid three ethyl ester (by acetic acid quality plan) as catalyst under the conditions of dehydration, cracking ethylene ketone acetate made, conversion rate is about 85%90%, on vinyl ketone selectivity (corporeal quantity meter ) is about 90%95%. Reaction equation: CH3COOH CH2 = C = O+H2O+147 kJ / mol.