A process for the recovery of palladium elements from production wastewater

Abstract

The application discloses a process method for recovering palladium elements from production wastewater, and comprises the following steps: heating SUZUKI coupling reaction production wastewater, then performing temperature reduction crystallization, aging, and suction filtration; adding the obtained filter cake into an organic solvent and an inorganic alkali aqueous solution, heating and refluxing, and then performing suction filtration and drying, so as to recover the palladium elements. The synthesis method is stable in process, mild in condition, simple in operation, and suitable for industrial application.

Description

Technical Field

[0001] This invention belongs to the field of pharmaceutical chemistry technology, and more specifically, relates to a process for recovering palladium from industrial wastewater. Background Technology

[0002] The androgen biosynthesis inhibitor tablets are marketed under the name Zytiga and are available as oral tablets.

[0003] Androgen biosynthesis inhibitors are converted into deacetylated products in vivo and can inhibit 17α-hydroxylase / C17,20-lyase (CYP17), which is expressed in testicular, adrenal, and prostate tumor tissues and is essential for androgen biosynthesis.

[0004] CYP17 catalyzes two consecutive reactions: 1) the conversion of pregnenolone and progesterone into their respective 17α-hydroxy derivatives via 17α-hydroxylase; and 2) the subsequent formation of dehydroepiandrosterone (DHEA) and androstenedione, respectively, catalyzed by C17,20 lyases. Both DHEA and androstenedione are androgens and precursors of testosterone. Inhibition of CYP17 by deacetylated androgen biosynthesis inhibitors also leads to increased production of adrenal mineralocorticoids.

[0005] Androgen-sensitive prostate cancer can respond to androgen-lowering therapies. Androgen blocking therapies such as GnRHa or orchiectomy can reduce androgen production in the testes, but do not affect androgen production in the adrenal glands or tumors.

[0006] The specific structure of androgen biosynthesis inhibitors is as follows:

[0007]

[0008] British Technology Group disclosed a method for preparing an androgen biosynthesis inhibitor in World Patent WO95 / 09178A, with the following reaction equation:

[0009]

[0010] Starting with dehydroepiandrosterone (DHEA), an A4 androgen biosynthesis inhibitor was generated through a multi-step reaction. In the preparation of the androgen biosynthesis inhibitor, the third step, the SUZUKI coupling reaction (preparation of A3), used a large amount of the catalyst "bis(triphenylphosphine)palladium dichloride," and the wastewater contained a large amount of palladium. Summary of the Invention

[0011] To reduce the environmental pollution caused by waste liquid containing heavy metals, the inventors have developed a safe, highly operable, low-cost, and environmentally friendly palladium recovery process.

[0012] The Journal of Southwest Normal University, April 1987, Issue 2, reported a process for recovering palladium dichloride using ammonia precipitation. This process requires repeated treatment with ammonia, hydrochloric acid, etc. for precipitation, which is cumbersome and causes significant pollution.

[0013] The August 2015 issue of the *Chinese Journal of Nonferrous Metals* (Vol. 25, No. 8) reported a method for recovering palladium using sodium sulfite. In this process, under concentrated sulfuric acid conditions, sodium sulfite is used to generate sulfurous acid, which is then used to further reduce palladium ions to recover the palladium metal. However, the sulfurous acid generated in this process produces a large amount of sulfur dioxide, causing significant environmental pollution.

[0014] The inventors have developed a process for extracting and recovering palladium from wastewater from the production of androgen biosynthesis inhibitors, overcoming the shortcomings of existing technologies.

[0015] This invention provides a process for extracting and recovering palladium from wastewater from the production of androgen biosynthesis inhibitors, wherein the chemical structure of the androgen biosynthesis inhibitor is as follows:

[0016]

[0017] In an embodiment of the present invention, the present invention provides a process for extracting and recovering palladium from wastewater from the production of androgen biosynthesis inhibitors, comprising the following steps:

[0018] (1) Using the production wastewater from the coupling reaction of androgen biosynthesis inhibitor SUZUKI as raw material, heat it;

[0019] (2) Cool down the heated liquid from step (1) to allow it to crystallize, grow crystals, and age.

[0020] (3) The crude palladium recovery product was obtained by vacuum filtration;

[0021] (4) Add the crude palladium recovery product obtained in step (3) to an organic solvent and an inorganic alkaline aqueous solution, reflux, filter, and dry.

[0022] Preferably, in step (1), the production wastewater from the coupling reaction of the androgen biosynthesis inhibitor SUZUKI is used as raw material, and the heating temperature is controlled at 55-75℃, preferably 65℃.

[0023] Preferably, the heating time in step (1) is 1-3 hours, preferably 2 hours.

[0024] Preferably, the temperature for cooling and crystallization in step (2) is 10-40℃, and more preferably 20-30℃.

[0025] Preferably, the time for cooling and crystallization in step (2) is 1-3 hours, preferably 2 hours.

[0026] Preferably, the aging temperature in step (2) is 10-40℃, and more preferably 20-30℃.

[0027] Preferably, the aging time in step (2) is 1-3 hours, preferably 2 hours.

[0028] Preferably, the organic solvent in step (4) is an ether, a halogenated hydrocarbon, an alcohol, an alkane, or an aromatic hydrocarbon, and preferably tetrahydrofuran.

[0029] Preferably, the inorganic base in step (4) is sodium hydroxide or potassium hydroxide, preferably potassium hydroxide.

[0030] Preferably, the filtration temperature in step (4) is 30-60℃, and more preferably 40-50℃.

[0031] Compared with existing technologies, the palladium recovery process of the present invention avoids the use of ammonia, sulfur-containing reagents, peroxide reagents, etc., reduces environmental pollution, improves operational safety, and provides a process method suitable for industrial production. Detailed Implementation

[0032] The embodiments of the present invention will be further described below through specific examples. For those skilled in the art, modifications can be made to the following examples based on the teachings of the present invention and existing technology, but these modifications still fall within the scope of protection claimed by the present invention.

[0033] Example 1

[0034] Preparation of crude palladium recovery product

[0035] Wastewater from step A3, an inhibitor of androgen biosynthesis, was added to a 500L glass-lined reactor. The temperature was controlled at 65℃, and the mixture was stirred and refluxed for 2 hours. After cooling the reaction solution to 20-30℃ and stirring to cultivate crystals for 2 hours, the mixture was allowed to stand and age for 8 hours. 280g of gray-black crude palladium recovery product was obtained by filtration.

[0036] Preparation of palladium recovery

[0037] 280 g of crude palladium recovery product, 5600 ml of tetrahydrofuran, and 1960 ml of 5% potassium hydroxide solution were added to a 10 L reaction flask to obtain a black suspension, which was heated under reflux for 1 hour. The suspension was cooled to 40-50 °C, filtered while hot, rinsed with 560 ml of water, and then rinsed with 840 ml of THF. The solid was dried at 50 °C to constant weight to obtain 102 g of black palladium recovery product. The Pd content was analyzed to be 76%, and the total palladium recovery rate was 80.7%.

[0038] Example 2

[0039] Preparation of crude palladium recovery product

[0040] Wastewater from step A3, an inhibitor of androgen biosynthesis, was added to a 500L glass-lined reactor. The temperature was controlled at 65℃, and the mixture was stirred and refluxed for 2 hours. After cooling the reaction solution to 20-30℃ and stirring to cultivate crystals for 2 hours, the mixture was allowed to stand and age for 8 hours. Filtering yielded 326g of gray-black crude palladium recovery product.

[0041] Preparation of palladium recovery

[0042] 280 g of crude palladium recovery product, 5600 ml of tetrahydrofuran, and 1960 ml of 5% potassium hydroxide solution were added to a 10 L reaction flask to obtain a black suspension, which was heated under reflux for 1 hour. The suspension was cooled to 40-50 °C, filtered while hot, rinsed with 560 ml of water, and then rinsed with 840 ml of THF. The solid was dried at 50 °C to constant weight to obtain 132 g of black palladium recovery product. The Pd content was determined to be 62%, and the total palladium recovery rate was 79.4%.

Claims

1. A process for extracting and recovering palladium from wastewater from the production of androgen biosynthesis inhibitors, comprising the following steps: (1) Using the production wastewater from the coupling reaction of androgen biosynthesis inhibitor SUZUKI as raw material, heating; (2) Cool the heated liquid from step (1) to allow it to crystallize, grow crystals, and age. (3) The crude palladium recovery product was obtained by vacuum filtration; (4) Add the crude palladium recovery product obtained in step (3) to an organic solvent and an inorganic alkaline aqueous solution, reflux, filter, and dry; in, The organic solvent in step (4) is tetrahydrofuran; the inorganic base is sodium hydroxide or potassium hydroxide.

2. The process method as described in claim 1, wherein, Step (1) uses the production wastewater from the coupling reaction of androgen biosynthesis inhibitor SUZUKI as raw material and heats it at a controlled temperature of 55-75℃.

3. The process method as described in claim 2, wherein, Step (1) Heating temperature control 65℃.

4. The process method as described in claim 1, wherein, The heating time for step (1) is 1-3 hours.

5. The process method as described in claim 4, wherein, The heating time for step (1) is 2 hours.

6. The process method as described in claim 1, wherein, Step (2) The temperature for cooling and crystallization is 10-40℃.

7. The process method of claim 6, wherein, Step (2) The temperature for cooling and crystallization is 20-30℃.

8. The process method as claimed in claim 1, wherein, Step (2) involves cooling down to allow crystals to form and grow crystals for 1-3 hours.

9. The process method of claim 8, wherein, Step (2) involves cooling down to allow crystals to crystallize and grow for 2 hours.

10. The process method of claim 1, wherein, Step (2) The aging temperature is 10-40℃.

11. The process method of claim 10, wherein, Step (2) The aging temperature is 20-30℃.

12. The process method of claim 1, wherein, Step (2) The aging time is 1-3 hours.

13. The process method of claim 12, wherein, Step (2) The aging time is 2 hours.

14. The process method as claimed in claim 1, wherein, The inorganic base mentioned in step (4) is potassium hydroxide.

15. The process method of claim 1, wherein, Step (4) The filtration temperature is 30-60℃.

16. The process method of claim 15, wherein, Step (4) The filtration temperature is 40-50℃.

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