Method for preparing 3-mercaptopropionic acid

A technology of mercaptopropionic acid and hydrochloric acid, which is applied in the field of preparation of 3-mercaptopropionic acid, can solve the problems of high cost, low yield, and difficult marketization of products, and achieve the effects of cheap price, reduced production cost, and no environmental pollution

CN101125827AInactive Publication Date: 2008-02-20顾建荣
0 Cites 19 Cited by

Patent Information

Authority / Receiving Office
CN · China
Current Assignee / Owner
Publication Date
2008-02-20
Estimated Expiration
Not applicable · inactive patent

Smart Images

  • Figure 1
    Figure 1
  • Figure 2
    Figure 2
  • Figure 3
    Figure 3
Patent Text Reader

Abstract

The invention relates to a preparation method of 3-mercaptopropionic acid. Sodium hydroxide solution, sodium hydrosulfide and sodium polysulfide (as catalyst) are mixed, then acrylonitrile is dripped into the mixture at the temperature of 20-70 DEG C to produce under insulated temperature the mixed solution of a plurality of intermediates, then hydrochloric acid is added for acidification and iron powder is added for deoxidization, thus acquiring the solution of 3-mercaptopropionic acid. The raw material sodium hydrosulfide selected in the reaction is cheap, reducing the production cost; hydrogen sulfide gas that is produced after the hydrochloric acid is added can be recycled to produce hydrogen sulfide nano, the production cost is further reduced; the final waste liquid mainly contains surplus hydrochloric acid and ammonia chloride, which is easy to be disposed; pollution is hardly caused during the whole reaction process.
Need to check novelty before this filing date? Find Prior Art

Description

technical field

[0001] The invention relates to a preparation method of 3-mercaptopropionic acid. Background technique

[0002] In the prior art, 3-mercaptopropionic acid is an intermediate for the preparation of medicine fenarol, and can also be used in biochemical research, antioxidants, plastic additives, etc. Its structural formula is: SHCH2CH2COOH

[0003] The existing technology adopts the following steps to implement:

[0004] CH2CHCN+CS(NH2)2+HCI——→(NH2)2CHSCH2CH2CN

[0005] <chemistry num="0001"> <chem file="200710132404_CML001.XML" / > < / chemistry>

[0006] After mixing thiourea and hydrochloric acid, add acrylonitrile dropwise to react, then add 4% sodium hydroxide to remove ammonia gas. After the solution is neutralized to acidity with hydrochloric acid, it is extracted with a solvent, the solvent is recovered, and the finished product is obtained by distillation under reduced pressure. In this method, because thiourea is relatively expen...

Examples

Embodiment Construction

[0023] The present invention will be further described below in conjunction with embodiment, but does not limit the present invention.

[0024] Preparation of synthetic solution:

[0025] Add 250 grams of sodium hydrosulfide with a concentration of 30%, 12 grams of sodium hydroxide, 20 grams of water, and 3 grams of catalyst sodium disulfide into the reaction pot and stir, then add 54 grams of acrylonitrile dropwise at 25°C for reaction, and keep warm after the addition is complete. After 10 hours, 450 grams of industrial hydrochloric acid with a concentration of 30% was added to the above synthetic liquid, and the temperature was raised to reflux for 3 hours.

[0026] reduction:

[0027] The temperature of the above acidified solution was lowered to 30°C, 40 grams of iron powder was added to react, and the temperature was raised to 100°C for 0.5 hours.

[0028] Extraction, Distillation:

[0029] Add 500 grams of toluene to the above reducing solution, stir, and separate la...