Preparation of a catalyst containing copper and silica
    1.
    发明授权
    Preparation of a catalyst containing copper and silica 失效
    制备含铜和二氧化硅的催化剂

    公开(公告)号:US4780448A

    公开(公告)日:1988-10-25

    申请号:US14072

    申请日:1987-01-30

    CPC分类号: B01J23/72 C07C29/149

    摘要: A catalyst containing copper and silica is prepared by a process in which an aqueous alkali metal silicate solution containing from 1 to 26% by weight of SiO.sub.2 is brought to a pH of from 0.5 to 2.0 with nitric acid, an aqueous copper nitrate solution containing from 5 to 15% by weight of Cu is added, after the addition of the nitric acid, so that a clear solution containing from 0.18 to 3.0 moles of Cu per mole of SiO.sub.2 is formed, the resulting solution is mixed with an aqueous alkali metal carbonate solution at from 40.degree. to 80.degree. C., the pH of the mixture being kept at from 7.5 to 8.5, and the precipitated material is separated off, dried, calcined by heating at from 250.degree. to 400.degree. C. and pressed in a conventional manner to give catalyst moldings. The catalyst thus obtained is used for the hydrogenation of dialkyl dicarboxylates to diols.

    摘要翻译: 含有铜和二氧化硅的催化剂是通过一种方法制备的,其中含有1至26重量%的SiO 2的碱金属硅酸盐水溶液用硝酸使其pH为0.5至2.0,硝酸铜水溶液含有 加入5〜15重量%的Cu后,加入硝酸后,形成每摩尔SiO 2含有0.18〜3.0摩尔Cu的透明溶液,得到的溶液与碱金属碳酸盐水溶液 溶液在40〜80℃下,将混合物的pH值保持在7.5〜8.5,析出的物质分离出来,干燥,在250〜400℃下加热煅烧, 常规方式提供催化剂模塑。 由此获得的催化剂用于将二羧酸二烷基酯氢化成二醇。

    Recovery of N-ethylpiperazine by distillation
    3.
    发明授权
    Recovery of N-ethylpiperazine by distillation 失效
    通过蒸馏回收N-乙基哌嗪

    公开(公告)号:US5626724A

    公开(公告)日:1997-05-06

    申请号:US510562

    申请日:1995-08-02

    CPC分类号: C07D295/03 C07D295/023

    摘要: In a process for the recovery of N-ethylpiperazine by distillation from mixtures with N,N'-diethylpiperazine, piperazine, ethanol, water and accompanying substances, water is added in a manner such that, at the location of the addition of the water, the piperazine concentration is greater than the N-ethylpiperazine concentration. The water may be added to the reflux to the top of the column.

    摘要翻译: 在与N,N'-二乙基哌嗪,哌嗪,乙醇,水和伴随物质的混合物中蒸馏回收N-乙基哌嗪的方法中,加入水,使得在添加水的位置, 哌嗪浓度大于N-乙基哌嗪浓度。 水可以加入回流至塔顶。