DTPA (Diethylenetriaminepentaacetic Acid) meta-neutral salt as well as preparation method and application thereof

Abstract

The invention relates to the technical field of synthesis of DTPA (Diethylenetriaminepentaacetic Acid) meta-neutral salt, and discloses the DTPA meta-neutral salt and a preparation method. The DTPA meta-neutral salt has a general structure as shown in the description, wherein R is any one of Na, K and NH4. The preparation method comprises the following steps of: firstly controlling the temperatureto be 35 DEG C or below, and dropwise adding a sodium hydroxide solution into a chloroacetic acid solution; then dropwise adding diethylenetriamide, and dropwise adding the sodium hydroxide solutioninto the mixed solution after completing the adding of the diethylenetriamide; controlling the temperature of the mixed solution to be 30 to 40 DEG C, regulating the pH (Potential of Hydrogen) value of the mixed solution to be 1.5 to 1.7 by using a hydrochloric acid solution of which the volume concentration is 50 percent, standing overnight, carrying out suction filtration, washing by icy water,and drying, thus obtaining DTPA; enabling the obtained DTPA to react with an alkaline solution or a strongly alkaline and weakly acidic salt solution, and controlling the reaction temperature to be 40to 60 DEG C; finally rising the temperature of the mixed solution to be 80 to 90 DEG C, reacting for 1 to 3 hours, evaporating until supersaturation, crystallizing by ethanol, carrying out suction filtration, washing by ethanol, and drying, thus finally obtaining the DTPA meta-neutral salt. According to the preparation method disclosed by the invention, the DTPA meta-neutral salt which has efficient complexing ability, is soluble, stable and non-irritant and has high purity is prepared. The invention also provides application of the DTPA meta-neutral salt.

Description

technical field [0001] The invention relates to the technical field of DTPA partial neutral salt synthesis, in particular to a DTPA partial neutral salt and its preparation method and application. Background technique [0002] With the increasingly serious environmental pollution, the probability of people being exposed to heavy metals (including radioactive metal nuclides) is getting higher and higher. After heavy metal ions contact the skin, a small amount of ions penetrate into the subcutaneous tissue and enter the tissue, and the long-term accumulation will have a serious impact on the human body. In addition, heavy metal ions on the body surface can enter the body in many ways (such as inhalation and ingestion), which can damage human health and cause great harm to the human body. Different metals have different effects on various organs of the human body. If the heavy metal is radioactive, it may not only enter the body to form internal radiation, but also adhere to t...

AI Technical Summary

Problems solved by technology

However, pentasodium diethylenetriaminepentaacetic acid is strongly alkaline, with a pH value of 11.2 to 11.5, which is extremely irritating to the skin (because the surface of the human skin is weakly acidic), and cannot be applied to heavy metals and radioactive metals on the surface of the human body. Nuclide decontamination, so it is necessary to prepare high-purity DTPA neutral salt, and ensure a very strong complexing ability and solubility

[0004] At present, the industrial production method of DTPA has the following two kinds: the first method is the chloroacetic acid method, for example, the Chinese invention patent application document announcement number is CN101607921A, a kind of preparation method of diethylenetriaminepentaacetic acid, diethylenetriaminepentaacetic acid pentasodium synthesis Process research ("Chemical Industry and Engineering Technology" (2008.29.(1).18-19)), DTPA chelating agent and its manufacture ("Paper and Papermaking" (2005.3.63-64)), DTPA synthesis process research ("Paper Chemicals" (1997.9 (4). 7-10)), paper chemical DTPA synthesis research ("China Paper" (1997.5. 68-69)) and other documents have introduced the method, the method uses chlorine Synthesis of raw materials such as acetic acid, diethylenetriamine and sodium hydroxide or sodium carbonate has a relatively simple process, but a large amount of by-product sodium chloride will be produced during the production process, and the obtained DTPA crude product needs to be desalted and purified. In addition, the production In the process, chloroacetic acid is easy to hydrolyze, which seriously affects the yield of DTPA

[0005] The second method is the sodium cyanide method, such as the research on the synthesis method of DTPA ("Leather Chemical Industry" (2002.19. (5). 26-28)), the synthesis of diethylenetriaminepentaacetic acid ("Chemical Industry and Engineering Technology" (2006.27.(6).24-25)) and other documents have introduced this method, adopt raw materials such as sodium cyanide and formaldehyde and diethylenetriamine to synthesize, and the advantage of this method is easy and simple to operate, and cost is lower, and product quality is good, No by-product sodium chloride is produced, but this method uses highly toxic cyanide as a raw material, making production management difficult to control

[0006] At present, most domestic production of DTPA adopts the chloroacetic acid method, but the general yield is low, and the yield reported in the literature is mostly below 80%. In addition, the impurity content is high, the salt content is high, and the refining process is backward, so it cannot compete with similar foreign products in the market.

Moreover, there are no highly efficient complexing, soluble, high-purity DTPA partial neutral salt related products on the market, and there is no relevant literature report, so a kind of DTPA partial neutral salt and its preparation method have important practical significance

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