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    32.
    发明专利
    未知

    公开(公告)号：ID16007A

    公开(公告)日：1997-08-28

    申请号：ID963809

    申请日：1996-12-19

    Applicant: DEGUSSA

    Inventor： HASSEBERG HANS ALBRECHT DR ,  HASSELBACH HANS JOACHIM DR ,  HUTHMACHER KLAUS DR ,  HAFNER VOLKER ,  HEINZEL HARALD ,  JAGER BARBARA

    IPC: C07C319/20 ,  C07C319/28 ,  C07C323/52

    Abstract: PCT No. PCT/EP96/05437 Sec. 371 Date Sep. 1, 1998 Sec. 102(e) Date Sep. 1, 1998 PCT Filed Dec. 5, 1996 PCT Pub. No. WO97/23452 PCT Pub. Date Jul. 3, 1997A method for the isolation of 2-hydroxy-4-methylthiobutyric acid (MHA), wherein MHA is isolated from a reaction mixture obtained by addition of hydrogen cyanide (HCN) to methylmercaptopropionaldehyde (MMP) and hydrolysis by sulphuric acid of the methylmercaptopropionaldehyde cyanohydrin (MMP-CH) thus obtained. The reaction mixture is brought into contact in a liquid/liquid extraction system with an organic solvent substantially immiscible with water, in order to form an extraction solution which contains the solvent and the MHA transferred out of the reaction mixture. By bringing the salt content of the reaction mixture, prior to the liquid/liquid extraction, to a concentration of about >50 wt. % (wt./wt.), preferably >55 wt. %, referred to the sum of the inorganic constituents of the reaction mixture, the coordinated use of energy in the total system is improved, the evaporation of strongly corrosive solutions is avoided, the efficiency of the hydrolysis step is increased and the distribution coefficients during the extraction are improved. The MHA is isolated as the extract from this extraction solution by evaporation, and may be used as animal feed supplement.

    33.
    发明专利
    未知

    公开(公告)号：MX5737E

    公开(公告)日：1984-01-30

    申请号：MX910580

    申请日：1980-10-17

    Applicant: DEGUSSA

    Inventor： SUCHSLAND HELMUT ,  HAFNER VOLKER ,  KLEEMANN AXEL

    IPC: C07C253/08 ,  C07C20060101 ,  C07C67/00 ,  C07C253/00 ,  C07C255/24 ,  C07C255/61 ,  C07C121/18

    Abstract: The invention is directed to a process for the production of iminodiacetonitrile by reaction of hexamethylenetetramine with hydrogen cyanide in acidic aqueous mediums. In this process the pH during the reaction which is 5.5 to 7.5 at the beginning is progressively lowered, altogether around 0.5 to 3.5 units and free formaldehyde is present only to a slight extent. Through this and in contrast to the known processes the formation of byproducts is suppressed and iminodiacetonitrile is produced directly in very good yields and sufficiently pure for further use.

    Process for preparing triallyl cyanurate
    35.
    发明专利
    Process for preparing triallyl cyanurate 未知

    公开(公告)号：AU2007276289A1

    公开(公告)日：2008-01-24

    申请号：AU2007276289

    申请日：2007-06-25

    Applicant: EVONIK DEGUSSA GMBH

    Inventor： HAFNER VOLKER ,  SUCHSLAND HELMUT ,  WERLE PETER

    IPC: C07D251/34

    Abstract: The invention relates to an improved process for preparing triallyl cyanurate (TAC) by reacting cyanuric chloride with allyl alcohol in the presence of an alkali metal acid acceptor and in the absence of an organic solvent other than allyl alcohol. According to the invention, TAC is obtained in over 99% purity with an APHA colour number below 10 in a yield of over 90% when 3.9 to 6.0 mol of allyl alcohol and 3.0 to 3.2 equivalents of acid acceptor are used per mole of cyanuric chloride, cyanuric chloride and acid acceptor are added simultaneously or successively to anhydrous or at least 50% by weight aqueous allyl alcohol, and the reaction is performed in one or more stages at a temperature in the range of -5 to +50°C.

    36.
    发明专利
    未知

    公开(公告)号：ES2196464T3

    公开(公告)日：2003-12-16

    申请号：ES98122921

    申请日：1998-12-02

    Applicant: DEGUSSA

    Inventor： HASSEBERG HANS-ALBRECHT DR ,  HASSELBACH HANS-JOACHIM DR ,  HUTHMACHER KLAUS DR ,  HAFNER VOLKER ,  HEINZEL HARALD

    IPC: B01D53/34 ,  B01D53/50 ,  B01D53/77 ,  C01B17/58 ,  C01B17/74 ,  C07C319/20 ,  C07C319/28 ,  C07C323/52 ,  C07C323/60

    Abstract: Recovery of sulfuric acid used in hydrolysis of methylmercaptopropionaldehyde-cyanohydrin is carried out by combustion of sulfates produced during the reaction to give a sulfur dioxide-containing mixture, which is then reacted with hydrogen peroxide. Recovery of sulfuric acid used in hydrolysis of methylmercaptopropionaldehyde-cyanohydrin (MMP-CH) comprises converting sulfate salt precipitates produced during the hydrolysis to SO2 in a furnace. The SO2-containing mixture is passed through an aqueous solution containing sulfuric acid and hydrogen peroxide, to convert the SO2 back to sulfuric acid. An Independent claim is also included for preparation of 2-hydroxy-4-methylthiobutyric acid (MHA) by hydrolysis of MMP-CH in the presence of sulfuric acid to give MHA and ammonium hydrogen sulfate and/or ammonium sulfate. The MHA is isolated and the sulfuric acid is recovered and recycled using the above method.

    38.
    发明专利
    未知

    公开(公告)号：TR199802563A2

    公开(公告)日：1999-06-21

    申请号：TR9802563

    申请日：1998-12-09

    Applicant: DEGUSSA

    Inventor： HASSEBERG DR HANS ALBRECHT ,  HUTHMACHER DR KLAUS ,  HAFNER VOLKER ,  HEINZEL HARALD ,  HASSELBACH DR HANS JOACHIM

    IPC: B01D53/34 ,  B01D53/50 ,  B01D53/77 ,  C01B17/58 ,  C01B17/74 ,  C07C319/20 ,  C07C319/28 ,  C07C323/52 ,  C07C323/60 ,  C01B17/90 ,  C07C327/06 ,  B09B3/00

    Abstract: Recovery of sulfuric acid used in hydrolysis of methylmercaptopropionaldehyde-cyanohydrin is carried out by combustion of sulfates produced during the reaction to give a sulfur dioxide-containing mixture, which is then reacted with hydrogen peroxide. Recovery of sulfuric acid used in hydrolysis of methylmercaptopropionaldehyde-cyanohydrin (MMP-CH) comprises converting sulfate salt precipitates produced during the hydrolysis to SO2 in a furnace. The SO2-containing mixture is passed through an aqueous solution containing sulfuric acid and hydrogen peroxide, to convert the SO2 back to sulfuric acid. An Independent claim is also included for preparation of 2-hydroxy-4-methylthiobutyric acid (MHA) by hydrolysis of MMP-CH in the presence of sulfuric acid to give MHA and ammonium hydrogen sulfate and/or ammonium sulfate. The MHA is isolated and the sulfuric acid is recovered and recycled using the above method.

    39.
    发明专利
    未知

    公开(公告)号：ID21414A

    公开(公告)日：1999-06-10

    申请号：ID981593

    申请日：1998-12-08

    Applicant: DEGUSSA

    Inventor： HASSEBERG HANS ALBRECHT ,  HASSELBACH HANS JOACHIM ,  HUTHMACHER KLAUS ,  HAFNER VOLKER ,  HEINZEL HARALD

    IPC: B01D53/34 ,  B01D53/50 ,  B01D53/77 ,  C01B17/58 ,  C01B17/74 ,  C07C319/20 ,  C07C319/28 ,  C07C323/52 ,  C07C323/60

    Abstract: Recovery of sulfuric acid used in hydrolysis of methylmercaptopropionaldehyde-cyanohydrin is carried out by combustion of sulfates produced during the reaction to give a sulfur dioxide-containing mixture, which is then reacted with hydrogen peroxide. Recovery of sulfuric acid used in hydrolysis of methylmercaptopropionaldehyde-cyanohydrin (MMP-CH) comprises converting sulfate salt precipitates produced during the hydrolysis to SO2 in a furnace. The SO2-containing mixture is passed through an aqueous solution containing sulfuric acid and hydrogen peroxide, to convert the SO2 back to sulfuric acid. An Independent claim is also included for preparation of 2-hydroxy-4-methylthiobutyric acid (MHA) by hydrolysis of MMP-CH in the presence of sulfuric acid to give MHA and ammonium hydrogen sulfate and/or ammonium sulfate. The MHA is isolated and the sulfuric acid is recovered and recycled using the above method.

    Process for obtaining 2-hydroxy-4-methylthiobutyric acid (mha)
    40.
    发明专利
    Process for obtaining 2-hydroxy-4-methylthiobutyric acid (mha) 未知

    公开(公告)号：AU1190697A

    公开(公告)日：1997-07-17

    申请号：AU1190697

    申请日：1996-12-05

    Applicant: DEGUSSA

    Inventor： HASSEBERG HANS-ALBRECHT ,  HASSELBACH HANS-JOACHIM ,  HUTHMACHER KLAUS ,  HAFNER VOLKER ,  HEINZEL HARALD ,  JAGER BARBARA

    IPC: C07C319/20 ,  C07C319/28 ,  C07C323/52

    Abstract: PCT No. PCT/EP96/05437 Sec. 371 Date Sep. 1, 1998 Sec. 102(e) Date Sep. 1, 1998 PCT Filed Dec. 5, 1996 PCT Pub. No. WO97/23452 PCT Pub. Date Jul. 3, 1997A method for the isolation of 2-hydroxy-4-methylthiobutyric acid (MHA), wherein MHA is isolated from a reaction mixture obtained by addition of hydrogen cyanide (HCN) to methylmercaptopropionaldehyde (MMP) and hydrolysis by sulphuric acid of the methylmercaptopropionaldehyde cyanohydrin (MMP-CH) thus obtained. The reaction mixture is brought into contact in a liquid/liquid extraction system with an organic solvent substantially immiscible with water, in order to form an extraction solution which contains the solvent and the MHA transferred out of the reaction mixture. By bringing the salt content of the reaction mixture, prior to the liquid/liquid extraction, to a concentration of about >50 wt. % (wt./wt.), preferably >55 wt. %, referred to the sum of the inorganic constituents of the reaction mixture, the coordinated use of energy in the total system is improved, the evaporation of strongly corrosive solutions is avoided, the efficiency of the hydrolysis step is increased and the distribution coefficients during the extraction are improved. The MHA is isolated as the extract from this extraction solution by evaporation, and may be used as animal feed supplement.

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