Dual bed xylene isomerization
    2.
    发明授权
    Dual bed xylene isomerization 失效
    双床二甲苯异构化

    公开(公告)号:US5516956A

    公开(公告)日:1996-05-14

    申请号:US342322

    申请日:1994-11-18

    摘要: A mixture of aromatic hydrocarbons, comprising ethylbenzene and at least one xylene, is isomerized using a two component catalyst system to convert the ethylbenzene to compounds that may be removed from the aromatic hydrocarbon stream and to produce a product stream wherein the para-xylene concentration is approximately equal to the equilibrium ratio of the para-isomer. The first catalyst comprises an intermediate pore size zeolite that is effective for ethylbenzene conversion. The first catalyst is preferably silica-bound. The second catalyst comprises an intermediate pore size zeolite, which further has a small crystal size and which is effective to catalyze xylene isomerization. Each of the catalysts of this invention may contain one or more hydrogenation/dehydrogenation component.

    摘要翻译: 使用双组分催化剂体系将包含乙苯和至少一种二甲苯的芳族烃混合物转化成可将乙苯转化成可从芳烃流中除去的化合物,并产生产物流,其中对二甲苯浓度为 大约等于对位异构体的平衡比。 第一种催化剂包括对乙苯转化有效的中等孔径的沸石。 第一催化剂优选是二氧化硅结合的。 第二种催化剂包括中等孔径的沸石,其进一步具有小的晶体尺寸并且有效催化二甲苯异构化。 本发明的每种催化剂可以含有一种或多种氢化/脱氢组分。

    Dual-loop xylene isomerization process
    5.
    发明授权
    Dual-loop xylene isomerization process 有权
    双环二甲苯异构化工艺

    公开(公告)号:US5977420A

    公开(公告)日:1999-11-02

    申请号:US139463

    申请日:1998-08-25

    IPC分类号: C07C15/08 C07C1/00 C07C5/22

    CPC分类号: C07C15/08 C07C2529/00

    摘要: A method for increasing the efficiency of xylene isomerization by using a two stage isomerization process. In the first stage of the process, a C.sub.9.sup.+ aromatics feedstock is subjected to ethylbenzene conversion and xylene isomerization. Non-C.sub.8 aromatics are removed from the effluent, which is then processed in a second stage of the process to remove para-xylene and isomerize the para-xylene depleted effluent. The effluent from the second stage isomerization unit is then recycled into the inlet of the second stage of the process and a slip stream from the para-xylene separator is recycled to the feedstock and to the effluent of the ethylbenzene conversion unit. In this way, the production of para-xylene is maximized. In a preferred embodiment, toluene is co-fed into the feedstock to minimize the loss of xylenes during the ethylbenzene conversion reaction.

    摘要翻译: 一种通过使用两级异构化方法提高二甲苯异构化效率的方法。 在该方法的第一阶段,C9 +芳烃原料进行乙苯转化和二甲苯异构化。 从流出物中除去非-C 8芳族化合物,然后在该方法的第二阶段中处理以除去对二甲苯并使对二甲苯贫乏的流出物异构化。 然后将来自第二级异构化单元的流出物再循环到该方法的第二阶段的入口中,并且来自对二甲苯分离器的滑流再循环至原料和乙苯转化单元的流出物。 以这种方式,对二甲苯的生产最大化。 在优选的实施方案中,将甲苯共同进料到原料中以使乙苯转化反应期间二甲苯的损失最小化。