Methods for recovering acrylic acid
    1.
    发明授权
    Methods for recovering acrylic acid 失效
    回收丙烯酸的方法

    公开(公告)号:US06252110B1

    公开(公告)日:2001-06-26

    申请号:US09104358

    申请日:1998-06-25

    IPC分类号: C07C5702

    摘要: A method for recovering acrylic acid from high boiling impurities containing acrylic acid dimer, acrylic acid and maleic acid at high efficiency with stability which includes the steps of (1) introducing said high boiling impurities containing acrylic acid dimer, acrylic acid and maleic acid into an acrylic acid recovery column, distilling acrylic acid from the column top and recovering the same, (2) introducing bottom liquid A from said acrylic acid recovery column into a pyrolyzing tank to decompose the acrylic acid dimer in the bottom liquid A, and (3) recirculating at least a part of bottom liquid B from said pyrolyzing tank into the acrylic acid recovery column.

    摘要翻译: 一种从高沸点杂质中回收丙烯酸的方法,该方法具有稳定的高效率,包括以下步骤:(1)将含有丙烯酸二聚体,丙烯酸和马来酸的所述高沸点杂质引入到丙烯酸二聚体,丙烯酸和马来酸中 丙烯酸回收塔,从塔顶蒸馏丙烯酸并回收其,(2)将底部液体A从所述丙烯酸回收塔引入热解罐中以分解底部液体A中的丙烯酸二聚体,和(3) 将至少一部分底部液体B从所述热解槽再循环到丙烯酸回收塔中。

    Stabilization and transport of &agr;, &bgr;-unsaturated carboxylic acid and removal of stabilizer
    2.
    发明授权
    Stabilization and transport of &agr;, &bgr;-unsaturated carboxylic acid and removal of stabilizer 失效
    稳定和运输α,β-不饱和羧酸和去除稳定剂

    公开(公告)号:US06207859B1

    公开(公告)日:2001-03-27

    申请号:US09404415

    申请日:1999-09-23

    IPC分类号: C07C5702

    CPC分类号: C07C51/47 C07C51/50 C07C57/04

    摘要: A process for inhibiting free-radical polymerization of an alpha,beta-unsaturated (&agr;,&bgr;-unsaturated) carboxylic acid, and for providing desired grade &agr;,&bgr;-unsaturated carboxylic acid for use following storage and transport is described herein. In particular, bulk storage and shipment such as with overseas transport is described. The process comprises combining the &agr;,&bgr;-unsaturated carboxylic acid with a phenolic inhibitor and a coinhibitor to form an inhibited mixture, storing the inhibited mixture, transporting the inhibited mixture, and removing the coinhibitor to provide the desired grade &agr;,&bgr;-unsaturated carboxylic acid for use. In preferred embodiments, the &agr;,&bgr;-unsaturated carboxylic acid is acrylic acid, the phenolic inhibitor is p-methoxyphenol, the coinhibitor is manganese cation, and removal of the coinhibitor is carried out using an ion exchange resin.

    摘要翻译: 本文描述了一种用于抑制α,β-不饱和(α,β-不饱和)羧酸的自由基聚合以及用于在储存和运输之后用于提供所需的等级α,β-不饱和羧酸的方法。 具体来说,大量存储和运输如海运。 该方法包括将α,β-不饱和羧酸与酚类抑制剂和联合抑制剂组合以形成抑制的混合物,储存被抑制的混合物,运输被抑制的混合物,以及除去联合抑制剂以提供所需的等级α,β-不饱和羧酸 酸使用。 在优选的实施方案中,α,β-不饱和羧酸是丙烯酸,酚类抑制剂是对甲氧基苯酚,联合抑制剂是锰阳离子,并且使用离子交换树脂进行去除联合抑制剂。

    Method for carrying out the catalytic gas phase oxidation of propene to form acrylic acid
    7.
    发明授权
    Method for carrying out the catalytic gas phase oxidation of propene to form acrylic acid 失效
    进行催化气相氧化丙烯以形成丙烯酸的方法

    公开(公告)号:US06740779B1

    公开(公告)日:2004-05-25

    申请号:US10110227

    申请日:2002-04-22

    IPC分类号: C07C5702

    CPC分类号: C07C51/25 C07C57/04

    摘要: In a process for the two-stage catalytic gas-phase oxidation of propene to acrylic acid, the reaction gas starting mixture is passed, in a tube-bundle reactor, with a propene loading of ≧160 l (S.T.P.) of propene/l·h, first over a fixed catalyst bed 1 present in two successive temperature zones A, B and then over a fixed catalyst bed 2 which is housed either in one further temperature zone C or in two further temperature zones D, E, the temperature of the zone A being kept at a lower temperature than the zone B and the temperature of the zone D at a lower temperature than the zone E.

    摘要翻译: 在将丙烯二阶段催化气相氧化成丙烯酸的过程中,将反应气体起始混合物在管束反应器中以丙烯/丙烯的加入量为约160l(STP)/ 1h 首先在存在于两个连续的温度区域A,B中的固定的催化剂床1上,然后在固定的催化剂床2上,该固定的催化剂床2容纳在一个另外的温度区域C或两个另外的温度区域D,E中, A在比区域B低的温度下保持在比区域B低的温度和区域D的温度。