 |
| Quantity: | |
|---|---|
Tartaric acid is also known as 2,3-dihydroxysuccinic acid, dihydroxysuccinic acid and grape acid. Because tartaric acid molecule contains two identical asymmetric carbon atoms, there are three optical isomers. Tartaric acid includes D-tartaric acid, L-tartaric acid and DL tartaric acid. Tartaric acid is colorless transparent prismatic crystal or powder, with strong acid taste and slight taste. It is soluble in water, and widely exists in many plants in nature in the form of potassium salt or calcium salt, with more grape content. Tartaric acid is made from the yellow crystals deposited at the bottom of the barrel when brewing wine, so it is called tartaric acid. Its sour taste is about 1.3 times as much as citric acid, and its use is similar to citric acid. Its solid is easily soluble in water, so it is suitable for making foaming drinks.
Tartaric acid crystal contains one molecule of crystal water, odorless, stable in the air, sour, acid threshold 0.0025%, acid intensity about 1.2~1.3 times of citric acid, slightly astringent in taste, with odor of baking sugar when burning, and metal ion chelation. 1g is about to dissolve in 0.8mL water (25 ℃), 0.5mL boiling water and 3mL ethanol. The pH of 0.3% aqueous solution is 2.4. DL tartaric acid is widely used as food additive, vitamin C effervescent tablets, salifying acidifier of organic base drugs (choline bitartrate), etc. Tartaric acid can form acid salt and neutral salt with alkali.
There are three main methods to prepare tartaric acid:
1. DL-tartaric acid is prepared by oxidation of fumaric acid or maleic acid.
2. It is obtained from the reaction of glyoxal with hydrocyanic acid and then acid hydrolysis. D-tartaric acid is found in many fruits or other parts of many plants. It exists in free state and in combination with potassium, calcium and magnesium.
3. Tartaric acid is prepared from the coarse tartar precipitate generated during the production of wine, extracted from potassium hydrogen tartrate, converted into calcium tartrate, acidified with dilute sulfuric acid, or oxidized by nitric acid D-glucose. The preparation of DL-tartaric acid is to azeotrope D-tartaric acid with NaOH aqueous solution. Mix 49 g of maleic anhydride, 0.25 g of tungstic acid, 130 g of 30% hydrogen peroxide and 50 ml of water evenly, stir for reaction at 70 ℃ for 8 hours, and add flow for 1 hour. Cool the reaction solution, add 5ml of concentrated sulfuric acid, heat and boil for 1 hour. Cooling, precipitation and crystallization. Filter, wash the filter cake with water for three times, drain and dry to obtain 5 grams of tartaric acid.
Tartaric acid is often used in the preparation of drugs, mordant and tanning agent, and also used as a reagent for the resolution of racemic basic compounds. It is also an acid taste agent in food additives, and its acid sense is better than malic acid and lactic acid. Its several salts have important applications, such as the preparation of Fehling reagent with potassium and sodium tartrate in the laboratory to identify the aldehyde functional group in the organic molecular structure. Its potassium sodium salt is also known as Rochelle salt. Its crystal polarizes under pressure, resulting in potential difference (piezoelectric effect) between the two ends of the surface, which can be made into piezoelectric elements for radio and cable radio receivers and pickups. Antimony potassium tartrate (commonly known as tartar emesis) is used to treat schistosomiasis in medical treatment.
Tartaric acid is also known as 2,3-dihydroxysuccinic acid, dihydroxysuccinic acid and grape acid. Because tartaric acid molecule contains two identical asymmetric carbon atoms, there are three optical isomers. Tartaric acid includes D-tartaric acid, L-tartaric acid and DL tartaric acid. Tartaric acid is colorless transparent prismatic crystal or powder, with strong acid taste and slight taste. It is soluble in water, and widely exists in many plants in nature in the form of potassium salt or calcium salt, with more grape content. Tartaric acid is made from the yellow crystals deposited at the bottom of the barrel when brewing wine, so it is called tartaric acid. Its sour taste is about 1.3 times as much as citric acid, and its use is similar to citric acid. Its solid is easily soluble in water, so it is suitable for making foaming drinks.
Tartaric acid crystal contains one molecule of crystal water, odorless, stable in the air, sour, acid threshold 0.0025%, acid intensity about 1.2~1.3 times of citric acid, slightly astringent in taste, with odor of baking sugar when burning, and metal ion chelation. 1g is about to dissolve in 0.8mL water (25 ℃), 0.5mL boiling water and 3mL ethanol. The pH of 0.3% aqueous solution is 2.4. DL tartaric acid is widely used as food additive, vitamin C effervescent tablets, salifying acidifier of organic base drugs (choline bitartrate), etc. Tartaric acid can form acid salt and neutral salt with alkali.
There are three main methods to prepare tartaric acid:
1. DL-tartaric acid is prepared by oxidation of fumaric acid or maleic acid.
2. It is obtained from the reaction of glyoxal with hydrocyanic acid and then acid hydrolysis. D-tartaric acid is found in many fruits or other parts of many plants. It exists in free state and in combination with potassium, calcium and magnesium.
3. Tartaric acid is prepared from the coarse tartar precipitate generated during the production of wine, extracted from potassium hydrogen tartrate, converted into calcium tartrate, acidified with dilute sulfuric acid, or oxidized by nitric acid D-glucose. The preparation of DL-tartaric acid is to azeotrope D-tartaric acid with NaOH aqueous solution. Mix 49 g of maleic anhydride, 0.25 g of tungstic acid, 130 g of 30% hydrogen peroxide and 50 ml of water evenly, stir for reaction at 70 ℃ for 8 hours, and add flow for 1 hour. Cool the reaction solution, add 5ml of concentrated sulfuric acid, heat and boil for 1 hour. Cooling, precipitation and crystallization. Filter, wash the filter cake with water for three times, drain and dry to obtain 5 grams of tartaric acid.
Tartaric acid is often used in the preparation of drugs, mordant and tanning agent, and also used as a reagent for the resolution of racemic basic compounds. It is also an acid taste agent in food additives, and its acid sense is better than malic acid and lactic acid. Its several salts have important applications, such as the preparation of Fehling reagent with potassium and sodium tartrate in the laboratory to identify the aldehyde functional group in the organic molecular structure. Its potassium sodium salt is also known as Rochelle salt. Its crystal polarizes under pressure, resulting in potential difference (piezoelectric effect) between the two ends of the surface, which can be made into piezoelectric elements for radio and cable radio receivers and pickups. Antimony potassium tartrate (commonly known as tartar emesis) is used to treat schistosomiasis in medical treatment.
