SU899116A1 - Method of regenerating desactivated catalyst for racemation of optically active aminoacids - Google Patents

Description

I

The invention relates to the racemization of optically active amino acids using polymer catalysts, in particular, to a method for regenerating a polymer catalyst deactivated during operation.

Methods are known for producing polymer catalysts for racemization of optically active amino acids based on polymer resins by introducing into the polymer matrix aromatic nuclei with aldehyde and hydroxy groups located in ortho-position 1, and also by introducing into the polymer matrix already containing aromatic nuclei with hydroxy groups of aldehyde groups in ortho-position to the next 2J.

. The catalysts obtained by these methods exhibit high activity in the racemization of optically active amino acids.

However, during prolonged (500-1000 hours) contact with an amino acid solution, the activity of polymer catalysts for racemization decreases. One of the reasons for this phenomenon may be sorption on the catalysts of condensation products of amino acids that block the active centers.

The purpose of the invention is to provide a method for regenerating the deactivated 10 when contacted with amino acids of said polymer catalyst for the racemization of optically active amino acids.

The goal is achieved

ts that the deactivated catalysts are treated with a solution of ammonia or alkali (NaOH, KOH) with a concentration of 1-25% at 20-100 C.

Claims (2)

Example 1. The catalyst obtained by method l is kept in lysine solution for 1000 h, then washed with water and dried. To 1 g processed3. In this way a catalyst is added with a solution of 2 g of D-lysine and 0.18 5Hj, 0 in 20 ml of water and heated at 100 ° C, complete racemization is achieved in an hour. On a freshly prepared catalyst, complete racemization of O-lysine under similar conditions x is reached in 5 hours. The catalyst obtained according to method 1.2) is kept in lysine analogously, after which it is complete racemysis | Qi O-lysine on it under conditions, with rarely higher, reached in 20 hours. Complete racemization of lysine on freshly prepared catalyst is reached in 6 hours. i Example 2. 1 g of catalyst (.1), decontaminated according to example 1, is kept in 30 ml of a 10-h aqueous ammonia solution for 10 hours, then washed with water and dried. Complete racemization of O-lysine on the catalyst thus treated is achieved in 11 hours. Example 3. 1 g of catalyst (.2), decontaminated according to example 1, kept in 15 ml of a 25% aqueous solution of MN at -3 m, then washed with water and dried. Complete racemization of O-lysine on the catalyst is achieved in 10 hours. Example. 1g of the SP catalyst deactivated by Example 1 is kept in 0 ml of a 1% aqueous solution of NaOH for 5 m, then washed with water and dried. Complete racemization of O-lysine on the catalyst is achieved in 8 hours. Example 5. 1 g of catalyst 11), decontaminated according to example 1, is kept in 10 ml of 10% aqueous solution of NaOH at 90 ° C for 2 hours, then washed with water and dried. Complete racemization of O-lysine on the catalyst is achieved in hours. PRI me R 6. 1 g of catalyst (2), deactivated in Example 1, is kept in 10 ml of a 10% KOH solution in an alcohol-water mixture (Cs, H50H: 5: 1) at 75 ° C for 3 hours, then washed with water and dried. Complete racemization of O-lysine on the catalyst is achieved in 8 hours. Claims of the invention A method for regenerating a deactivated catalyst for racemization of optically active amino acids, representing it. a polymer containing aromatic nuclei with ortho-positioned aldehyde and hydroxy groups, which consists in that the deactivated catalyst is treated with a solution of ammonia or alkali with a concentration of 1-25 at 20-100 ° C. Sources of information taken into account during the examination 1. USSR author's certificate No. 68675, cl. B 01 T-37/00, 1979. 2. USSR author's certificate number 659181, cl. B 01 J 37/00, 1979.