柠檬酸单水合物
Citric acid monohydrate
CAS: 5949-29-1
Molecular Formula: C6H10O8
柠檬酸单水合物 - Names and Identifiers
| Name | Citric acid monohydrate |
| Synonyms | citric CITRIC ACID H2O Citricacidhydrate Citric acid Mono Hydrous citric acid Citric acid hydrate Citronensαure-hydrat Citric acid Monohydride Citric acid monohydrate Citric acid, monohydrate Citric Acid Monohydrate BP HYDROXYTRICARBALLYLIC ACID MONOHYDRATE BETA-HYDROXY-TRICARBOXYLIC ACID MONOHYDRATE citric acid free acid monohydrate*crystalline 2,3-propanetricarboxylicacid,2-hydroxy-monohydrate 1,2,3-Propanetricarboxylicacid,2-hydroxy-,monohydrate 2-Hydroxy-1,2,3,propane-tricarboxylic acid, monohydrate 1,2,3-Propanetricarboxylic acid, 2-hydroxy-, monohydrate |
| CAS | 5949-29-1 |
| EINECS | 200-662-2 |
| InChI | InChI=1/C6H8O7.H2O/c7-3(8)1-6(13,5(11)12)2-4(9)10;/h13H,1-2H2,(H,7,8)(H,9,10)(H,11,12);1H2 |
| InChIKey | YASYEJJMZJALEJ-UHFFFAOYSA-N |
柠檬酸单水合物 - Physico-chemical Properties
| Molecular Formula | C6H10O8 |
| Molar Mass | 210.1388 |
| Density | 0.791g/mLat 25°C(lit.) |
| Melting Point | -94°C(lit.) |
| Boling Point | 56°C760mm Hg(lit.) |
| Flash Point | 1°F |
| Water Solubility | 1630 g/L (20 oC) ;H2O: soluble 54% (w/w) at 10°C (Citric acid in water) |
| Solubility | Soluble in methanol and water |
| Vapor Presure | 184 mm Hg ( 20 °C) |
| Vapor Density | 2 (vs air) |
| Appearance | White crystal or powder |
| Specific Gravity | 0.810 (20/4℃) |
| Color | White |
| Merck | 14,2326 |
| BRN | 4018641 |
| pKa | 3.138, 4.76, 6.401 |
| PH | 1.85 (50g/l, H2O, 25℃) |
| Storage Condition | no restrictions. |
| Stability | Stable. Incompatible with oxidizing agents, bases, reducing agents, nitrates. |
| Sensitive | Hygroscopic |
| Refractive Index | n20/D 1.359(lit.) |
| MDL | MFCD00149972 |
| Physical and Chemical Properties | Density 1.54 melting point 135-152°C flash point 173.9°C water-soluble 1630g/L (20°C) |
| Use | It is mainly used as a sour agent for food, and is also used for the preparation of pharmaceutical coolants, detergent additives, etc. |
柠檬酸单水合物 - Risk and Safety
| Risk Codes | R11 - Highly Flammable R36 - Irritating to the eyes R66 - Repeated exposure may cause skin dryness or cracking R67 - Vapors may cause drowsiness and dizziness R41 - Risk of serious damage to eyes R36/37/38 - Irritating to eyes, respiratory system and skin. R37/38 - Irritating to respiratory system and skin. |
| Safety Description | S9 - Keep container in a well-ventilated place. S16 - Keep away from sources of ignition. S26 - In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. S37/39 - Wear suitable gloves and eye/face protection S36/37/39 - Wear suitable protective clothing, gloves and eye/face protection. S36 - Wear suitable protective clothing. |
| UN IDs | UN 1090 3/PG 2 |
| WGK Germany | 1 |
| RTECS | AL3150000 |
| TSCA | Yes |
| HS Code | 29181400 |
| Toxicity | LD50 orally in Rabbit: 3000 mg/kg |
柠檬酸单水合物 - Upstream Downstream Industry
柠檬酸单水合物 - Reference
| Reference Show more | 1. Tang Suhua Liu Shouchun Wu Xiaohe Fu Shuyi Li Peiyao. Development of canned black fish [J]. Food Research and Development, 2019, 40(19):123-129. 2. Zhang Nanhai, Liu Rui-yu, Dong Yun-Rui, Guo Yi-san, Yu Qian-hui, Zhao Liang, Zhang Libing, Wang Cheng-Tao, Wu Wei, ji bao-ping, Ge Zhang-chun, Zhou Feng. Study on the acid reduction technology of blackberry juice resin and the preparation of its compound juice [J]. Food Science, 2020,41(10):281-287. 3. Hao ailing, Feng Li, Qin Yi, etc. Screening of citric acid-degrading yeast and its fermentation performance [J]. Chinese Journal of Food Science, 2018, 018(011):72-80. 4. Wang Jing, Wan Zhibo, Xu Chaoli, etc. Comparative analysis of organic acids in wine grape fruits from Xinjiang [J]. Modern food science and technology, 2020, v.36;No.246(02):75 255-260. 5. Li Biao, Li Chengjie, Chen Shuangyang, et al. Optimization of cooking technology and non-volatile characteristic flavor compounds of mushroom soup [J]. Journal of Food Science and Technology, 36(1). 6. Cui Wenjia, Li Xiao, Wang Yueming, etc. Study on desalination technology of pickled cucumber [J]. Food industry, 2018. 7. Fengting Li, Bo Zhou, Xiao Shen, et al. Fermentation characteristics of Lactobacillus plantarum in Mulberry pulp [J]. Sericulture science, 2018(5):746-752. 8. Ma Ning, Wang Chao-yi, Fang Dong Road, etc. Flavor variation of Flammulina velutipes packaged with polyethylene film during cold storage [J]. China Agricultural Science, 2019, 52(08):146-159. 9. Jiawen Li, Da Liu, Dansheng Liu, et al. Screening and preliminary study on exopolysaccharide-producing strain of lactic acid bacteria [J]. Chinese Journal of microecology, vol. 31, 2019, Issue 9, 1027-1033 pp. 10. Yu, the latest Wang rikui he Mingyang, etc. Accumulation of anthocyanins and its correlation with sugar and acid content during the ripening process of blood orange 'tarocos. 11. Wu Lin, Zhang Qiang, Mo Huiming, et al. Differential Analysis of sugar and acid components in Yunnan Lijiang and Jilin Jingyu blueberries [J]. China fruit tree 2019 No.200(06):60-64 70. 12. Wang Siwei, Liu Yanping, Wang Xiaonan, et al. Determination of 10 organic acids in fresh litchi pulp by high performance liquid chromatography-triple quadrupole tandem mass spectrometry [J]. Chinese Journal of pesticide science, 2019(3). 13. Chen Huali, Wu Jijun, Zhou Bo, et al. Effect of Acetobacter xylinum on the fermentation of compound juice by lactic acid bacteria [J]. Modern food science and technology, 2019, 35(03):131-138 145. 14. Pu Yunfeng, Ding Tian, Zhong Jianjun, etc. Nutritional Quality and antioxidant analysis of 12 kinds of dried fruits in Xinjiang [J]. Chinese Journal of Food Science, 2019, 19(05):293-300. 15. Yuan Qifeng, Yan Jiawen, Wang Honglin, Li Shipin, Chen Nan, Wang Yu, Han Xiumei, Ma Yuhua. Analysis of sugar, acid and vitamin components in the fruit of 'zixiang 1. China fruit tree, 2019(04):43-47. 16. Zou Ying, bu Zhibin, Yu Yuanshan, et al. Enzymatic preparation of purple potato juice and its lactic acid bacteria fermentation characteristics [J]. Science and Technology of food industry, 2020, v.41;No.442(02):22-26 32. 17. Duan Yunfei, Wu Guangbin, Ye Hong, Chen Zhao-hua, Zhang Yun, Chen FA-he. Simultaneous determination of seven organic acids in postharvest fruit of lotus fruit by HPLC [J]. Food Science, 2021,42(04):175-180. 18. Wang, Maoyu, Yan Huang, and Chuanhe Zhu. "Effects of lactic acid bacteria fermentation on organic acids, volatile aroma components, and sensory quality of Hawthorn pulp." IOP Conference Series: Earth and Environmental Science. Vol. 267. No. 6. IOP Publishi 19. Chen, Huali, et al. "High hydrostatic pressure and Co-fermentation by lactobacillus rhamnosus and gluconacetobacter xylinus improve flavor of yacon-litchi-longan juice." Foods 8.8 (2019): 308.https://doi.org/10.3390/foods8080308 20. Peng, Wanying, et al. "Effect of the apple cultivar on cloudy apple juice fermented by a mixture of Lactobacillus acidophilus, Lactobacillus plantarum, and Lactobacillus fermentum." Food Chemistry 340 (2021): 127922.https://doi.org/10.1016/j.foodchem.2020. 21. [IF=3] Qu Lala et al."Phenotypic assessment and ligand screening of ETA/ETB receptors with label-free dynamic mass redistribution assay."N-S Arch Pharmacol. 2020 Jun;393(6):937-950 |
柠檬酸单水合物 - Nature
Open Data Verified Data
colorless orthogonal columnar crystals or white crystalline particles. It is easily weathered in dry air and easily caked in humid air. Soluble in water and ethanol, slightly soluble in ether.
Last Update：2024-01-02 23:10:35
柠檬酸单水合物 - Preparation Method
Open Data Verified Data
with sugar solution as raw material, with Aspergillus niger fermentation, separation, purification. Or from fruit containing citric acid, such as lemon juice (available citric acid 5% ~ 8%), pineapple waste extract directly.
Last Update：2022-01-01 09:25:22
柠檬酸单水合物 - Standard
Authoritative Data Verified Data
This product is 2-hydroxypropane-1, 2, 3-tricarboxylic acid monohydrate. The content of C6H80 7 shall not be less than 99.5% calculated as anhydrous.
Last Update：2024-01-02 23:10:35
柠檬酸单水合物 - Trait
Authoritative Data Verified Data
- This product is colorless translucent crystals, white particles or white crystalline powder; Odorless, extremely sour; Slightly weathered in dry air; Acidic reaction in aqueous solution.
- This product is easily soluble in water, soluble in ethanol, and slightly soluble in ether.
Last Update：2022-01-01 11:23:46
柠檬酸单水合物 - Introduction
Verification of bismuth, nitrite, oxygen and water, determination of aluminum, copper, mercury, nickel, oxygen and thorium, as a multivalent chelating agent, remove trace metals, prepare a buffer solution, and determine blood potassium.
Last Update：2022-10-16 17:26:47
柠檬酸单水合物 - Use
Open Data Verified Data
A reagent for measuring bismuth, aluminum, copper, mercury, nickel, nitrite, nitrous acid, and the like. For the preparation of buffer, preparation of biological medium, alkali poisoning antidote. Together with picric acid, it is used for the determination of proteins in urine.
Last Update：2022-01-01 09:25:22
柠檬酸单水合物 - Differential diagnosis
Authoritative Data Verified Data
- this product in 105X: Drying for 2 hours, the infrared absorption spectrum should be consistent with the control spectrum (Spectrum set 263 figure).
- This product shows the identification reaction of citrate (General rule 0301).
Last Update：2022-01-01 11:23:46
柠檬酸单水合物 - Safety
Open Data Verified Data
rats were injected intraperitoneally with LD50:975mg/kg.
Last Update：2022-01-01 09:25:23
柠檬酸单水合物 - Exam
Authoritative Data Verified Data
clarity and color of solution
take this product 2. 0g, Add 10ml of water to dissolve, and check according to law (General rule 0901 and general rule 0902, first method), the solution should be clear and colorless; If color development occurs, it shall not be deeper in comparison with the yellow No. 2 or yellow-green No. 2 Standard Colorimetric solution (General rule 0901 method 1).
chloride
take lO.Og of this product and check it according to law (General rule 0801). Compared with the control solution made of 5. 0ml of standard sodium chloride solution, it should not be more concentrated (0. 0005%).
sulfate
take this product l .O g, check according to law (General rule 0802), compared with the standard potassium sulfate solution 1. 5ml made of the control solution, should not be more concentrated (0. 015%).
oxalate
after 10ml of water is added to dissolve l .O g of this product, ammonia test solution is added for neutralization, and 2ml of vaporized calcium test solution is added. Place at room temperature for 30 minutes without producing turbidity.
easily carbonized
take this product l.O g, in a colorimetric tube, add 95%(g/g) sulfuric acid 1 0 m l, heat at 90°C 1°C, immediately cool, such as color, compared with the control solution (0.9 of vaporized cobalt solution for color comparison, 8.9 of potassium dichromate solution for color comparison and 0. 2M l mixing) comparison, not deeper.
moisture
take this product, according to the water determination method (General rule 0832 first method 1), the water content is divided into 7 .5% ~ 9 .0%.
ignition residue
not over 0841 (general rule).
calcium salt
take l.O g of this product, add 10M l of water to dissolve, add ammonia test solution to neutralize, add several drops of ammonium oxalate test solution, and do not produce turbidity.
Iron Salt
take this product l.O g, check according to law (General rule 0807), after extraction with n-butanol, with standard iron solution 1. 0M l compared with the control solution made by the same method, not deeper (0. 001%).
Heavy metals
take this product 4 .0g, add 10M l of water to dissolve, add 1 drop of phenolphthalein indicator solution, add appropriate amount of ammonia test solution to the solution to show pink, add acetate buffer (ph3.5) the amount of 2m l and water shall be adjusted to 2 5 m l, which shall be checked according to law (through the first method of 0821), and the heavy metal content shall not exceed 5 parts per million.
arsenic salt
take 2.0g of this product, add water 23M l to dissolve, add hydrochloric acid 5ml, check according to law (General rule 0822 first law), should meet the requirements (0. 0001%).
Last Update：2022-01-01 11:23:47
柠檬酸单水合物 - Content determination
Authoritative Data Verified Data
take about 1.5g of this product, weigh it accurately, add 40ml of water to dissolve, add 3 drops of phenolphthalein indicator solution, and titrate with sodium hydroxide titration solution (lm o l/L). Each lm l sodium hydroxide titration solution (lm o l/ L) corresponds to 64.04mg of Hs O7.
Last Update：2022-01-01 11:23:48
柠檬酸单水合物 - Category
Authoritative Data Verified Data
pharmaceutical excipients, p H value regulator, stabilizer and acidifier.
Last Update：2022-01-01 11:23:48
柠檬酸单水合物 - Storage
Authoritative Data Verified Data
sealed storage.
Last Update：2022-01-01 11:23:48
柠檬酸单水合物 - Reference Information
| NIST chemical information | information provided by: webbook.nist.gov (external link) |
| EPA chemical substance information | information provided by: ofmpeb.epa.gov (external link) |
| Introduction | citric acid monohydrate is colorless crystal or white crystalline powder with a density of 1.54. Melting point 135-152 °c. Flash point 173.9 °c. Water soluble 1630g/L (20 degrees C). |
| properties | colorless crystalline or white crystalline powder. |
| Use | citric acid monohydrate is mainly used in food and beverage industry as acidulant, flavoring agent, preservative and antistaling agent. Also in the chemical industry, cosmetics industry and washing industry used as antioxidants, plasticizers, detergents mainly used as food acid, also used in the preparation of pharmaceutical cooling agent, determination of bismuth, nitrite, oxygen and water, determination of aluminum, copper, mercury, nickel, oxygen and thorium, used as sequestering agent to remove trace metals, preparation of buffer solution, determination of serum potassium. |
| production method | 1. Starch or sugar (such as sugar cane molasses) as raw material, prepared by fermentation. Sweet potato flour Disinfection fermentation↓ Aspergillus niger 26 ℃ filter mycelial washing filtrate heating → lime milk precipitation → Sulfuric acid neutralization → decolorization → resin exchange → crystallization → Citric Acid 2. First, 12%-16% of the sweet potato powder was sterilized, and then the pre-cultured Aspergillus niger Silk was inoculated for fermentation. In the fermentation process, ammonia water was added, and after 2-3 days of fermentation at 26 ℃, the mycelium was separated from the fermentation broth, and the water after washing the mycelium was added to the fermentation broth. Then heated to 90 ° C, with lime milk precipitation of citric acid, calcium citrate obtained with a slight excess of sulfuric acid decomposition of citric acid, filtration, filtrate with activated carbon decolorization, and then through the ion exchange resin to remove impurities, concentrated under reduced pressure of 60~70 ℃, cooled to not less than 36 6 ℃ conversion temperature, adding seed crystal, crystallization, cold air drying, can prepare citric acid product. 3. With sugar solution as raw material, with Aspergillus niger fermentation, separation, purification. Or from fruit containing citric acid, such as lemon juice (available citric acid 5% ~ 8%), pineapple waste extract directly. Starch-based raw materials such as dried potato, corn, etc. by Aspergillus niger fermentation, and then separated and purified to produce pure products. 5. This product is mainly produced by fermentation. Its raw materials can be molasses, sucrose, sweet potato and petroleum hydrocarbons and other carbohydrates. According to the fermentation method can be divided into two categories of surface fermentation and submerged fermentation, surface fermentation is the early production method, with some Penicillium or Aspergillus niger as the strain; Submerged fermentation method also with Aspergillus niger as the strain, in the process of fermentation, small spherical filamentous aggregates are formed, and the growing and thin filamentous cells should be avoided. The fermentation condition is that the pH value is 1.5~2.8, and at the same time, the sterile air should be introduced with stirring, after completion of fermentation, the filamentous cells and residual solid dregs were removed by filtration, and the filtrate was neutralized with calcium carbonate to obtain calcium citrate, and then neutralized with concentrated sulfuric acid to obtain crude citric acid, which was refined by ion exchange resin, concentration and crystallization gave the final product. |
Last Update：2024-04-09 15:16:51
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View History
柠檬酸单水合物
3-[((2R)-1-METHYLPYRROLIDIN-2-YL)METHYL]-5-[(E)-2-(PHENYLSULFONYL)VINYL]INDOLE
TRIETHYLENE GLYCOL extrapure AR
Methylphosphonyl chlorofluoride
4-乙酰氧基联苯
2-Hydroxy-2-phenyl-3-(1,4-dioxa-8-azaspiro[4.5]decan-8-yl)propionic acid 3-quinuclidinyl ester
bioban-s
2-Azetidinone,4-(2-pyrimidinylthio)-
硫代异烟酰胺
3-[((2R)-1-METHYLPYRROLIDIN-2-YL)METHYL]-5-[(E)-2-(PHENYLSULFONYL)VINYL]INDOLE
TRIETHYLENE GLYCOL extrapure AR
Methylphosphonyl chlorofluoride
4-乙酰氧基联苯
2-Hydroxy-2-phenyl-3-(1,4-dioxa-8-azaspiro[4.5]decan-8-yl)propionic acid 3-quinuclidinyl ester
bioban-s
2-Azetidinone,4-(2-pyrimidinylthio)-
硫代异烟酰胺
Raw Materials for 柠檬酸单水合物