Home  Products Search  Properties Search  中文版
Home > Dictionary > Information
Acetic acid;Ethanoic acid
Molecular formula : C2H4O2
MW : No. 60.050
CAS production specimen-19-7

nature : colorless and transparent liquid. 16.635 ° C melting point, boiling point, 117.9 ° C and relative density of 1.0492 (20 / 4 ° C) refractive index of 1.3716, flash point (open cup) 57 ° C, 465 ° C spontaneous combustion point, viscosity 11.83mPa s (20 ° C) . In pure acetic acid at 16 ° C, can be cleared from solid, it said acetic acid. With water, ethanol, benzene and ether Compatibility, not soluble in carbon disulfide. When water is added acetic acid, a mixture of the total volume of smaller, increase in density. Molecular ratio of 1:1, and further diluted and no more changes in the volume of the above. There irritating odor.

preparation methods : acid in the natural world wide distribution. For example, in fruit or vegetable oils, mainly in the form of esters; In animal tissue, blood and excreta free acid form. Many microbes can be different by fermentation of organic matter into acetic acid. Ancient Chinese vinegar alone on the records, as early as BC, have coaxed human liquor by the oxidation of various acid bacteria fermented vinegar, the late 19th century, the discovery of dry distillation of timber available acetic acid. In 1911, in Germany built the world's first set of acetaldehyde oxidation of acid production plant. Soon after the research and development of hydrocarbon oxidation of carbon acid production methods. In 1960 the original German methanol used in high pressure (20 MPa) by carbonylation acetic acid method. Subsequently, the United States used Monsanto rhodium complex catalyst (catalyst for Iodide), methanol carbonylation acetic acid pressure dropped to 0.3-MPa, and in 1970 built 135kt acid production of methanol carbonylation of low pressure chemical devices. Due to the advanced technical and economic law from the mid-1970s, new manufacturers to use more low-pressure methanol carbonylation law. In 1984, world production of acetic acid has coal 6Mt every year, low pressure oxo method about 40%. 1. Fermentation using starch fermentation from the Surface of desalination (containing 3-6% ethanol), the mother of vinegar bacteria role, to around 35 ° C for fermentation, short on the Surface air oxidation into vinegar. In addition to vinegar with 3-6% of the acid, also contain other organic acids, esters and protein. The fermentation system used primarily in vinegar. 2. It is a synthesis of industrial production of acetic acid method. (1) acetaldehyde oxidation. To acetaldehyde as raw materials, using air or oxygen as the oxidant, 50-80 ° C ,0.6-1.0 MPa and manganese catalyst in acid saved in the Tower Bubbling Reactor for liquid oxidation (see article industrial examples). (2) low pressure methanol carbonylation law. Monsanto has also said France. The use of rhodium carbonyl compounds and iodide catalyst system consisting of, methanol and carbon monoxide in the water in acid medium, and 175 ° C below MPa about the reaction conditions, generate acid. Because of the catalyst activity and selectivity are very high, so little reaction. Reaction products separately as components from dehydration towers and tower, advised the separation of the water and acid components can be recycled to reactor, the reactor from the first gas scrubber cold methanol to recover brought out the iodine methane (intermediate product), then to carbon monoxide Recovery Unit. Proceeds crude distillation products by purification products derived acetate. Methanol juice yield >99%. Low pressure methanol carbonylation acetic acid legal system with inexpensive raw materials, operating conditions ease, a high rate of acid production, product quality and process advantages of simple, acetic acid production technology of the most economically advanced methods. But the reaction medium of a serious corrosive, the need to use expensive special steel. (3) high-pressure methanol carbonylation of methanol and carbon monoxide law in acid aqueous reaction to cobalt carbonyl catalyst for methane iodine catalyst, the reaction conditions of 250 ° C and 70MPa. After the reaction product of separation after the separation system and receive a finished product. Methanol dollars, the yield up to 90%. (4) liquid carbon alkane oxidation. Butane is used as raw material for acetic acid as the solvent, 170-180 ° C, 5.5MPa and cobalt acid catalyst, the use of air oxidation of liquid oxidizer. We could also use LPG or light oil as raw material. This side of raw materials were relatively cheap, but the process is longer, corrosion and acid yield is not high, it is limited to a cheap butane or LPG supply to the local area will adopt. Companies such as the United States Celance butane oxidation, yield 76% formic acid by-product of 6%. As in the oil refinery 30-100 ° C for raw materials, the oxidation temperature 165-167 ° C, pressure 3.92 - 4.90MPa, naphthenic acid, cobalt catalyst into the fuel consumption of approximately 0.035 0.1. Air Oxidation liquid mixture of acid, six tower in acid, its oil yield of 40%. Each production 1t acetic acid, propionic acid by-products in 0.1t, succinic acid 0.02t, 0.12t formic acid, neutral acid 0.4t. Naphtha consumption of about 2.4t, catalyst 0.2kg. Acetic acid oxidation of acetaldehyde industrial examples : acetaldehyde and acetic acid manganese from the tower bottom of oxidation tower above leads to oxygen, the temperature in 70-75 ° C, the top gas pressure maintained at 9.81 × 104Pa, the tower leads to an appropriate amount of nitrogen gas to prevent an explosion. Continuous material. The formation of coarse acid solidification point in 8.5-9 ° C, and condensed into refining processes, cooling exhaust by hypothermia, condensate return oxidation tower, the gas empty. Enter consecutive rough acid concentration tower, temperature control tower at 95-103 ° C, the condenser condensate dilute acetic acid, the acid recovery column acid recovery, the gas condensate not enter into thin Cryo acetaldehyde reuse. The low boiling point to remove coarse acid consecutive evaporation pan by adding acid, the tower is maintained at a temperature around 120 ° C, the acid distillate namely finished. Bottom high boiling point and the catalyst can be burned to remove organic catalyst after recovery. Food ilizers acid used by the GB1903-80, the content of ?98.0%, impurity indicators should meet the requirements. Reagent Acid Purification Methods : industrial acid adding potassium permanganate powder (for acid weight of 1-2%), full mixing allows the dissolved. The amount should be kept within one hour of potassium permanganate fade. The final minutes to dissolve the lower part. The distillation column steamed acid to a new steamed into the appropriate acid powder chromic anhydride. It dissolved upper sdution get a distillation. Namely, from middle distillate products. The dehydration methods used acetic anhydride addition, it can also use ethyl acetate and n-butyl acetate, benzene, diisopropyl ether and water azeotropic composition of the mixture, azeotropic distillation dehydration.

purposes : acetate is the bulk chemical products, is the most important one of the organic acids. Mainly used in the production of vinyl acetate, acetic anhydride, acetate and cellulose acetate. Poly vinyl acetate can be made from films and adhesives, as well as synthetic materials Villeneuve. Cellulose acetate rayon can be created and the film. Lower alcohol formation of acetate is a good solvent, widely used in industrial paints. Acetic acid oxidation reaction is a good solvent (for example, oxidation of p-xylene production of PTA). Acetic acid is an organic synthesis of the important industrial raw materials for the synthesis of acetic anhydride, diethyl malonate, ethyl acetoacetate, halogenated acid, can also create drugs such as aspirin, pesticide 2,4-D and so on. Also used in the production of acetate, manganese, sodium, lead, aluminum, zinc, cobalt and ot
Notice:Each item can have many explanations from different angels. If you want grasp the item comprehensively,please see below "more details data".
More Detailed Data:
1) ethanoic acid;acetic acid
2) acetic acid
3) Acetic acid
4) Acetic acid
5) acetic acid
6) Glacial acetic acid;Acetic acid glacial
7) Acetic acid
8) Acetic acid
9) Toluylic acid
10) Chloroacetic acid;Chloroethanoic acid;Carboxymethyl chloride;Monochloroacetic acid
Notice Some description was translated by software and the data is only as a reference.
1) Chinese medicine preparation “Tianlongdanhua capsule?
2) Compound body-strengthening eucommia bark mixture for treating diseases caused by kidney Qi deficiency
3) Zaizao Pill for treating woman diseases
4) Asafoetide capsule for intestine and spleen
5) Bone-strengthening medicine and producing method thereof
6) Medicine for treating stranguria
7) Medicine for treating traumatic injury
8) Medicine for treating intestinal diseases
9) Medicine for treating mouth and gullet diseases
10) Medicine for treating woman diseases