Process for obtaining 2-hydroxy-4-methylthiobutyric acid (MHA)
    84.
    发明授权
    Process for obtaining 2-hydroxy-4-methylthiobutyric acid (MHA) 有权
    获得2-羟基-4-甲硫基丁酸(MHA)的方法

    公开(公告)号:US6140536A

    公开(公告)日:2000-10-31

    申请号:US91796

    申请日:1998-09-01

    CPC分类号: C07C319/28 C07C319/20

    摘要: A 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.

    摘要翻译: PCT No.PCT / EP96 / 05437 Sec。 371日期:1998年9月1日 102(e)1998年9月1日PCT PCT 1996年12月5日PCT公布。 公开号WO97 / 23452 日期1997年7月3日分离2-羟基-4-甲硫基丁酸(MHA)的方法,其中MHA是通过将氰化氢(HCN)加入到甲基巯基丙醛(MMP)中并通过硫酸水解而获得的反应混合物中分离的 的甲基巯基丙醛氰醇(MMP-CH)。 使反应混合物在液/液萃取系统中与基本上与水不混溶的有机溶剂接触,以形成含有溶剂和从反应混合物中转移的MHA的萃取溶液。 通过使液体/液体萃取之前的反应混合物的盐含量达到约> 50wt。 %(重量/重量),优选> 55重量% %,是指反应混合物的无机成分之和,改善了总体系中能量的协调使用,避免了强腐蚀性溶液的蒸发,提高了水解步骤的效率,提高了分散系数 提取提高。 通过蒸发将MHA作为来自该提取溶液的提取物分离,并且可以用作动物饲料添加剂。

    Process for the preparation of D,L-methionine or the salt thereof
    85.
    发明授权
    Process for the preparation of D,L-methionine or the salt thereof 失效
    制备D,L-甲硫氨酸或其盐的方法

    公开(公告)号:US5990349A

    公开(公告)日:1999-11-23

    申请号:US37020

    申请日:1998-03-09

    摘要: A process for the preparation of methionine or a salt of methionine by reaction of the components 3-methylmercaptopropionaldhyde, hydrogen cyanide, ammonia and carbon dioxide or components from which the above-mentioned components can be prepared, optionally in the presence of water, to 5-(2-methylmercaptoethyl)-hydantoin and further reaction thereof to methionine or the salt thereof, characterised in that the reaction of the components is initiated by means of at least one premixture in such a way that a first mixture is formed containing at least the predominant proportion (at least 5/10) of the 3-methylmercaptopropionaldeyde and at least 1/10 of the hydrogen cyanide component or corresponding quantities of components from which these components can be prepared, and less than 5/10 of one of the components ammonia, carbon dioxide or of the components from which ammonia or carbon dioxide can be prepared, and in that this first mixture is combined with the other component(s) for the reactive conversion to 5-(2-methylmercaptoethyl)-hydantoin, wherein this (these) latter component(s) may be premixed in one or more other mixtures.

    摘要翻译: 通过将3-甲基巯基丙酸,氰化氢,氨和二氧化碳或可由其制备上述组分的组分,任选地在水存在下,将组分3-甲基巯基丙酸,氰化氢,氨和二氧化碳或组分反应制备甲硫氨酸或甲硫氨酸的方法, - (2-甲基巯基乙基) - 乙内酰脲及其与甲硫氨酸或其盐的反应,其特征在于,组分的反应通过至少一种预混物引发,使得形成第一混合物至少含有 3-甲基巯基丙酸的主要比例(至少+ E,fra 5/10 + EE)和氰化氢组分的至少+ E,fra 1/10 + EE或可以制备这些组分的相应量的组分, 并且可以制备氨,二氧化碳或其中可以制备氨或二氧化碳的组分之一的小于+ E,fra 5/10 + EE,并且因为该第一混合物与 反应转化成5-(2-甲基巯基乙基) - 乙内酰脲的其它组分,其中这些(这些)后一种组分可以在一种或多种其它混合物中预混合。

    Method for the continuous preparation of methionine or methionine
derivatives
    90.
    发明授权
    Method for the continuous preparation of methionine or methionine derivatives 失效
    连续制备甲硫氨酸或甲硫氨酸衍生物的方法

    公开(公告)号:US5672745A

    公开(公告)日:1997-09-30

    申请号:US416900

    申请日:1995-05-23

    CPC分类号: C07C319/20

    摘要: The direct saponification of methionine nitrile obtained from methylmercaptopropionaldehyde, prussic acid and ammonia gives low yields, catalyst and educt losses and unwanted side-products. The aim of the invention is therefore to provide a method which can be carried out without isolating the intermediate products, in particular continuously, and with low losses. The ketone used is recovered in high yields after amide saponification since this liberates the ketone from side-products. In order to recover the ammonia, it is necessary for the ammonia to be substantially freed of ketone, the mixture of ammonia, ketone and water obtained being separated under pressure in a separation column. When the amide is saponified at .gtoreq.160.degree. C., amide concentrations of less than 25% by wt. are preferred. Methionine nitrile is produced by treatment with at least 4 equivalents of .gtoreq.50% by wt. ammonia at between 40.degree. and 80.degree. C./or between 5 and 60 min. Cyanide residues are destroyed by heating to over 150.degree. C. Methionine is of particular use as a feedstuff, in particular in aqueous solution.

    摘要翻译: PCT No.PCT / EP93 / 02838 Sec。 371日期:1995年5月23日 102(e)日期1995年5月23日PCT提交1993年10月14日PCT公布。 出版物WO94 / 08957 日期1994年4月28日由甲基巯基丙醛,氢氰酸和氨获得的甲硫氨酸腈的直接皂化产生低产率,催化剂和离子液体损失以及不需要的副产物。 因此,本发明的目的是提供一种方法,其可以在不隔离中间产物的情况下进行,特别是连续地且以低损耗隔离。 使用的酮在酰胺皂化后以高收率回收,因为这释放出来自副产物的酮。 为了回收氨,需要将氨基本上除去酮,得到的氨,酮和水的混合物在分离塔中在压力下分离。 当酰胺在≥160℃皂化时,酰胺浓度小于25重量% 是优选的。 甲硫氨酸腈通过用至少4当量≥50重量%进行处理来生产。 在40℃和80℃之间或在5和60分钟之间的氨。 氰化物残留物通过加热至150℃以上被破坏。甲硫氨酸特别用作饲料,特别是在水溶液中。