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    Cryogenic process for the separation of air to produce ultra high purity nitrogen
    35.
    发明授权
    Cryogenic process for the separation of air to produce ultra high purity nitrogen 失效
    用于分离空气以产生超高纯氮的低温工艺

    公开(公告)号：US5123947A

    公开(公告)日：1992-06-23

    申请号：US638853

    申请日：1991-01-03

    申请人： Rakesh Agrawal

    发明人： Rakesh Agrawal

    IPC分类号： F25J3/04

    CPC分类号： F25J3/04872 ,  F25J3/044 ,  F25J3/0443 ,  F25J3/04448 ,  F25J3/04454 ,  F25J2200/30 ,  F25J2200/32 ,  F25J2200/50 ,  F25J2200/54 ,  F25J2200/74 ,  F25J2200/94 ,  F25J2205/02 ,  F25J2215/44 ,  F25J2220/42 ,  F25J2220/44 ,  F25J2250/20

    摘要： This invention relates to a cryogenic process for the separation of air utilizing an integrated multi-column distillation system wherein an ultra high purity nitrogen product is generated. In the cryogenic distillation separation of air, air is initially compressed, pretreated and cooled for separation into its components. Ultra high purity, e.g., nitrogen typically having less than 0.1 ppm impurities is generated in a multi-column distillation system comprising a first column and an ultra high purity nitrogen column with enhanced nitrogen product recovery by withdrawing a gaseous nitrogen fraction from a first column and charging the fraction as a feed to the ultra high purity nitrogen column, withdrawing a nitrogen stream which is rich in volatile contaminants from the top of the ultra high purity nitrogen column and recovering a nitrogen product at a point below the removal point of the nitrogen rich stream containing volatile components. Removal of volatile components in the distillation process is effected by partially condensing a nitrogen vapor stream from either the first column or the ultra high purity column and removing at least one of the uncondensed portions of the nitrogen rich stream containing volatile components as a purge stream.

    摘要翻译： 本发明涉及一种使用集成的多塔蒸馏系统分离空气的低温方法，其中产生超高纯氮产物。 在空气的低温蒸馏分离中，空气最初被压缩，预处理并冷却以分离成其组分。 在包括第一塔和超高纯度氮塔的多塔蒸馏系统中产生超高纯度，例如通常具有小于0.1ppm杂质的氮，通过从第一塔中取出气态氮馏分而提高氮产物回收率， 将该馏分作为进料加入到超高纯氮塔中，从超高纯度氮塔的顶部排出富含挥发性污染物的氮气流，并在低于富氮的去除点的一个点回收氮产物 流含有挥发性成分。 通过将来自第一塔或超高纯度塔的氮蒸汽流部分冷凝并除去含有挥发性组分的富氮流的至少一个未冷凝部分作为吹扫流来实现蒸馏过程中挥发性组分的去除。

    Cryogenic process for the separation of air to produce moderate pressure nitrogen
    36.
    发明授权
    Cryogenic process for the separation of air to produce moderate pressure nitrogen 失效
    用于分离空气以生产中等压力氮的低温方法

    公开(公告)号：US5077978A

    公开(公告)日：1992-01-07

    申请号：US537181

    申请日：1990-06-12

    申请人： Rakesh Agrawal ,  Donald W. Woodward

    发明人： Rakesh Agrawal ,  Donald W. Woodward

    IPC分类号： F25J3/04

    CPC分类号： F25J3/042 ,  F25J3/04212 ,  F25J3/04309 ,  F25J3/04315 ,  F25J3/04412 ,  F25J3/04678 ,  F25J2200/20 ,  F25J2240/44 ,  F25J2245/50 ,  F25J2250/50 ,  Y10S62/924

    摘要： This invention relates to a cryogenic process for the separation of air utilizing an integrated multi-column distillation system wherein a nitrogen rich, oxygen rich and argon rich product are generated. In the cryogenic distillation separation of air, air is initially compressed, pretreated and cooled for separation into its components. Moderate pressure, e.g., 25-80 psia nitrogen is generated with enhanced nitrogen product purity and greater recovery of both nitrogen and argon by effecting a high boil-up rate in the bottom of the lower pressure column, thereby creating a reduced liquid flow/vapor flow ratio (L/V) and utilizing a higher than customary nitrogen reflux to the top of the lower pressure column, where the concentration of oxygen in nitrogen is less than about 10 ppm by volume or the nitrogen purity is at least about 99.5% by volume. Refrigeration to drive the system is obtained by recovering the energy from the waste nitrogen stream and oxygen vapor from the lower pressure column. A second method for obtaining refrigeration is to withdraw oxygen as a bottoms liquid from the lower pressure column, expanding that liquid to a lower pressure and using it to condense the nitrogen vapor generated in a higher pressure column which has been expanded in a turbo-expander to provide the refrigeration.

    Alkylation of aromatic amines over thermally pretreated zeolites
    37.
    发明授权
    Alkylation of aromatic amines over thermally pretreated zeolites 失效
    芳族胺在热预处理沸石上烷基化

    公开(公告)号：US5026912A

    公开(公告)日：1991-06-25

    申请号：US499925

    申请日：1990-03-27

    申请人： Rakesh Agrawal ,  Steven R. Auvil

    发明人： Rakesh Agrawal ,  Steven R. Auvil

    IPC分类号： C07C209/68

    CPC分类号： C07C209/68

    摘要： A process for selectively producing ortho-alkylated aromatic amines in high selectivity relative to N-alkylated aromatic amines. The process comprises reacting an aromatic amine, having at least one hydrogen atom in a position ortho to the amine functionality, and an olefin under conditions sufficient to effect an alkylation reaction, in the presence of a zeolite catalyst which has been thermally pretreated by heating the catalyst to a temperature greater than about 500.degree. C. for a period ranging from 0.5 to about 10 hours while sweeping an inert gas over the heated catalyst to remove water and ammonia formed during the thermal treatment, and subsequently recovering the alkylated aromatic amine.

    摘要翻译： 相对于N-烷基化芳族胺，以高选择性选择性地生产邻烷基化芳族胺的方法。 该方法包括在已经通过加热热预处理的沸石催化剂的存在下使具有至少一个氢原子的胺在官能团的位置与烯烃的反应条件下进行反应，所述烯烃在足以进行烷基化反应的条件下进行 催化剂在大约500℃的温度下进行约0.5至约10小时的时间，同时在加热的催化剂上吹扫惰性气体以除去在热处理期间形成的水和氨，随后回收烷基化芳族胺。

    Alkylation of toluenediamine and para-phenylenediamine with isobutylene in the presence of acidic, crystalline molecular sieves
    40.
    发明授权
    Alkylation of toluenediamine and para-phenylenediamine with isobutylene in the presence of acidic, crystalline molecular sieves 失效
    在酸性，结晶分子筛存在下，用异丁烯烷基化甲苯二胺和对苯二胺

    公开(公告)号：US4914237A

    公开(公告)日：1990-04-03

    申请号：US277096

    申请日：1988-11-29

    申请人： Rakesh Agrawal

    发明人： Rakesh Agrawal

    IPC分类号： C07C209/68

    CPC分类号： C07C209/68 ,  Y02P20/584

    摘要： This invention relates to an improvement in a fixed bed process for producing tert-butyl-derivatives of aromatic amines, e.g., para-phenylenediamine and toluenediamine by the reaction of isobutylene with the corresponding aromatic diamine in the presence of a highly acidic crystalline alumino-silicate catalyst. The improvement for regenerating the catalyst during operation constitutes adding sufficient water to the catalyst to provide sufficient saturation of the catalyst during the reaction and generally retard the reaction and then substantially decreasing the quantity of added water or reducing the amount of water added.

    摘要翻译： 本发明涉及通过在高度酸性的结晶铝硅酸盐存在下异丁烯与相应的芳族二胺的反应来生产芳族胺的叔丁基衍生物例如对苯二胺和甲苯二胺的固定床方法的改进 催化剂。 在操作期间再生催化剂的改进构成向催化剂中添加足够的水以在反应期间提供足够的催化剂饱和度，并且通常延迟反应，然后显着降低加入的水量或减少加入的水量。