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    Process for refining aqueous acid mixtures utilized in nitration of aromatics
    241.
    发明授权
    Process for refining aqueous acid mixtures utilized in nitration of aromatics 失效
    用于精炼用于芳族化合物硝化的含水酸混合物的方法

    公开(公告)号：US4257986A

    公开(公告)日：1981-03-24

    申请号：US8906

    申请日：1979-02-02

    Applicant: Barton Milligan ,  Der-Shing Huang

    Inventor： Barton Milligan ,  Der-Shing Huang

    IPC: C07C201/08 ,  C07C205/06 ,  C07C205/12 ,  C07C79/10

    CPC classification number: C07C201/08

    Abstract: This invention relates to an improvement in a process for the manufacture of a nitroaromatic compound produced by the mixed sulfuric-nitric acid nitration method. The improvement resides in the refining of the aqueous acid mixture and comprises the following sequential steps: (a) contacting the mixed aqueous acid mixture, after nitration, with an oxidizing or a reducing agent under conditions effective for removing contaminant nitrous acid; (b) contacting the aqueous acid mixture in step (a) with feed aromatic compound to remove contaminant organics and residual nitric acid and then, if necessary, (c) contacting the remaining acid mixture with sufficient oxidizing agent under oxidizing conditions to remove residual organic components.

    Abstract translation: 本发明涉及通过混合硫酸 - 硝酸硝化法制备硝基芳族化合物的方法的改进。 改进在于酸性混合物的精制，并包括以下顺序步骤：（a）硝化后的混合含水酸混合物与氧化还原剂在有效除去污染的亚硝酸的条件下接触; （b）将步骤（a）中的含水酸混合物与进料芳族化合物接触以除去污染有机物和残余硝酸，然后如果需要，（c）在氧化条件下将剩余的酸混合物与足够的氧化剂接触以除去残留的有机物 组件。

    Process for nitrating aromatic hydrocarbons
    242.
    发明授权
    Process for nitrating aromatic hydrocarbons 失效
    硝化芳烃的方法

    公开(公告)号：US4123466A

    公开(公告)日：1978-10-31

    申请号：US859388

    申请日：1977-12-12

    Applicant: Chung-Yuan Lin ,  Fred A. Stuber ,  Henri Ulrich

    Inventor： Chung-Yuan Lin ,  Fred A. Stuber ,  Henri Ulrich

    IPC: C07C201/08 ,  C07C205/06 ,  C07B11/00

    CPC classification number: C07C201/08

    Abstract: An improved process for the nitration of aromatic hydrocarbons is described. The aromatic hydrocarbon (benzene, toluene of particular interest) is reacted with gaseous nitrogen dioxide in the presence of a catalytic amount of sulfuric acid and in the absence of oxygen. The process is highly selective and avoids the formation of undesired by-products. The acid employed as catalyst can be recovered and recycled after removal of water of condensation liberated in the reaction.

    Abstract translation: 描述了用于芳烃的硝化的改进方法。 在催化量的硫酸存在下，在不存在氧气的情况下，使芳烃（特别令人关注的苯，甲苯）与气体二氧化氮反应。 该方法具有高选择性，避免了不希望的副产物的形成。 用作催化剂的酸可以在除去在反应中释放的冷凝水中回收和再循环。

    Nitration process
    245.
    发明授权
    Nitration process 失效
    硝化过程

    公开(公告)号：US3976704A

    公开(公告)日：1976-08-24

    申请号：US538723

    申请日：1975-01-06

    Applicant: Ronald J. Vaughan

    Inventor： Ronald J. Vaughan

    IPC: C07B43/02 ,  C07C201/08 ,  C07C205/06 ,  C07C205/12 ,  C07C205/22 ,  C07C205/37 ,  C07C205/57 ,  C07C207/00 ,  C07C79/10

    CPC classification number: C07C201/08 ,  C07B43/02

    Abstract: This invention relates to a process for the nitration of organic compounds, especially aromatic compounds, which comprises contacting said compound with a nitrating agent at conditions whereby a nitrated product is formed. The nitration agent and the compound are substantially separated by means of a polymeric membrane, said polymeric membrane preferably comprising sulfonic acid groups, pendant to the polymeric backbone. In a most preferred embodiment, the membrane is a perfluorosulfonic acid polymer. The use of this most preferred polymeric material as a membrane in the instant process allows the nitration of aromatic organic compounds to take place without the incorporation of strong sulfuric acid in the nitrating agent.

    Abstract translation: 本发明涉及硝化有机化合物，特别是芳族化合物的方法，其包括在形成硝化产物的条件下使所述化合物与硝化剂接触。 硝化剂和化合物通过聚合物膜基本上分离，所述聚合物膜优选包含垂饰于聚合物主链的磺酸基团。 在最优选的实施方案中，膜是全氟磺酸聚合物。 在本方法中使用这种最优选的聚合物材料作为膜，可以在不在硝化剂中引入强硫酸的情况下进行芳族有机化合物的硝化。

    Process for the mononitration of ortho-xylene
    246.
    发明授权
    Process for the mononitration of ortho-xylene 失效
    邻二甲苯一硝化方法

    公开(公告)号：US3929916A

    公开(公告)日：1975-12-30

    申请号：US47818974

    申请日：1974-06-11

    Applicant: AMERICAN CYANAMID CO

    Inventor： LEVY STEPHEN DAVID ,  RAUCH FRANCIS CLYDE

    IPC: C07C201/08 ,  C07C205/06 ,  C07C79/10

    CPC classification number: C07C201/08 ,  C07C205/06

    Abstract: There is provided a process for mononitrating ortho-xylene by reacting o-xylene with catalytic amounts of nitrogen tetroxide (N2O4) or nitrogen dioxide (NO2) and concentrated nitric acid in concentrations of at least 68% in the presence of a mercuric salt and an aliphatic monocarboxylic acid anhydride to obtain good yields of mononitrated o-xylene having an isomer distribution of at least a 70:30 ratio of 4- to 3- nitro-o-xylenes. Such 4nitro-o-xylene, upon separation from the isomeric mixture, finds utility in the preparation of xylidine derived preemergence herbicides.

    Abstract translation: 提供了一种通过邻位二甲苯与催化量的四氧化二氮（N 2 O 4）或二氧化氮（NO 2）和浓硝酸浓度在至少68％的浓度下在汞盐和 脂族单羧酸酐，以获得具有至少70:30比例的4-至3-硝基 - 邻二甲苯的异构体分布的单硝化邻二甲苯的良好产率。 在与异构体混合物分离时，这种4-硝基邻二甲苯可用于制备二甲苯胺衍生的芽前除草剂。

    Process for the preparation of nitroaromatic compounds
    247.
    发明授权
    Process for the preparation of nitroaromatic compounds 失效
    硝基芳族化合物的制备方法

    公开(公告)号：US3922315A

    公开(公告)日：1975-11-25

    申请号：US40998173

    申请日：1973-10-26

    Applicant: ATLANTIC RICHFIELD CO

    Inventor： MITCHELL JR MAURICE M ,  TOMEZSKO EDWARD S J

    IPC: C07C201/08 ,  C07C205/06 ,  C07C209/36 ,  C07C79/10

    CPC classification number: C07C209/36 ,  C07C201/08 ,  C07C205/06

    Abstract: Process for the mononitration of aromatic compounds through the use of nitrogen dioxide and/or its dimer, nitrogen tetroxide, in the presence of a rhodium catalyst. Also, by suitable adjustment of operating parameters the corresponding amino compound may be made from the produced nitro compound using the same contained rhodium catalyst.

    Abstract translation: 在铑催化剂存在下，通过使用二氧化氮和/或其二聚体，四氧化镧使芳族化合物单硝化的方法。 此外，通过适当调整操作参数，可以使用相同的含有铑催化剂的产生的硝基化合物制备相应的氨基化合物。

    Nitration with nitric acid and trifluoromethanesulfonic acid
    248.
    发明授权
    Nitration with nitric acid and trifluoromethanesulfonic acid 失效
    硝酸和三氟甲磺酸硝酸

    公开(公告)号：US3714272A

    公开(公告)日：1973-01-30

    申请号：US3714272D

    申请日：1972-02-07

    Applicant: STANFORD RESEARCH INST

    Inventor： COON C ,  HILL M

    IPC: C07B43/02 ,  C07C201/08 ,  C07C205/06 ,  C07C205/11 ,  C07C205/12 ,  C07C79/10 ,  C07C79/12

    CPC classification number: C07B43/02 ,  C07C201/08 ,  C07C205/06 ,  C07C205/11 ,  C07C205/12

    Abstract: TWO MOLES OF TRIFLUOROMETHANESULFONIC ACID COMBINE WITH ONE MOLE OF NITRIC ACID TO FORM A WHITE CRYSTALLINE SOLID HAVING EXCELLENT NITRATING CAPABILITIES WHEN EMPLOYED EITHER IN AN ORGANIC SOLVENT MEDIUM OR IN SULFURIC ACID OR AN EXCESS OF THE TRIFLUOROMETHANESULFONIC ACID. THE NITRATION REACTION CAN BE CONDUCTED USING ONE OR ANOTHER OF THESE MEDIA AT TEMPERATURES RANGING FROM ABOUT -110* TO 30*C., WITH ANY SIDE REACTIONS BEING SUBSTANTIALLY ABSENT. THE PROCESS IS CHARACTERIZED BY HIGH POSITIONAL SELECTIVITY, AND WHEN NITRATING TOLUENE TO DINITROTOLUENE, TOTAL CONTENT OF META ISOMERS CAN BE KEPT AT LEVELS WELL BELOW 1 PERCENT BY USING AN ORGANIC SOLVENT AND LOW TEMPERATURES. YIELDS EXCEED 98 PERCENT.

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