Preparation of polyoxymethylene dimethyl ethers by catalytic conversion of formaldehyde formed by oxidation of dimethyl ether
    1.
    发明授权
    Preparation of polyoxymethylene dimethyl ethers by catalytic conversion of formaldehyde formed by oxidation of dimethyl ether 失效
    通过二甲醚氧化形成的甲醛的催化转化制备聚甲醛二甲醚

    公开(公告)号:US06392102B1

    公开(公告)日:2002-05-21

    申请号:US09547515

    申请日:2000-04-12

    IPC分类号: C07C4700

    摘要: A particularly useful process which includes the steps of providing a feedstream comprising providing a source of formaldehyde formed by conversion of dimethyl ether in the presence of a catalyst comprising tungsten oxide; and (i) heating the feedstream with the heterogeneous acidic catalyst in a catalytic distillation column to convert methanol and formaldehyde present to methylal and higher polyoxymethylene dimethyl ethers and to separate the methylal from the higher polyoxymethylene dimethyl ethers is disclosed, and/or (ii) contacting the source of formaldehyde and a predominately dimethyl ether feedstream with a heterogeneous, condensation promoting catalyst capable of hydrating dimethyl ether under conditions of reaction sufficient to form an effluent comprising water, methanol, formaldehyde, dimethyl ether, and polyoxymethylene dimethyl ethers is disclosed. Unreacted dimethyl ether is recovered from the effluent and recycled to the formation of polyoxymethylene dimethyl ethers. The resulting dimethyl ether-free liquid mixture is heated in the presence of an acidic catalyst to convert at least the methanol and formaldehyde present to polyoxymethylene dimethyl ethers. Advantageously, methylal and higher polyoxymethylene dimethyl ethers are formed and separated in a catalytic distillation column. By including in the column an anion exchange resin, an essentially acid-free product is obtained which can be used directly as a blending component, or fractionated, as by further distillation, to provide more suitable components for blending into diesel fuel.

    摘要翻译: 一种特别有用的方法,其包括提供进料流的步骤,所述进料流包括在包含氧化钨的催化剂存在下提供由二甲醚转化而形成的甲醛源; 和(i)在催化蒸馏塔中加热具有异质酸性催化剂的进料流,以将甲醇和甲醛转化为甲醛和更高级的聚甲醛二甲醚,并将甲缩醛与高级聚甲醛二甲醚分开,和/或(ii) 公开了在足够形成包含水,甲醇,甲醛,二甲醚和聚甲醛二甲醚的流出物的反应条件下,使甲醛源和主要是二甲醚进料流与异构的缩合促进催化剂接触,该催化剂能够使二甲醚水合。 从流出物中回收未反应的二甲醚,再循环至形成聚甲醛二甲醚。 将所得的无二甲醚液体混合物在酸性催化剂存在下加热至少将甲醇和甲醛转化为聚甲醛二甲醚。 有利地,甲缩醛和更高级的聚甲醛二甲醚在催化蒸馏塔中形成并分离。 通过在柱中包含阴离子交换树脂,获得基本上不含酸的产品,其可以直接用作共混组分,或通过进一步蒸馏分离,以提供更合适的用于混合到柴油中的组分。

    Method for production of halogen-containing aromatic compound

    公开(公告)号:US06433231B1

    公开(公告)日:2002-08-13

    申请号:US09886805

    申请日:2001-06-21

    IPC分类号: C07C4700

    摘要: A method for producing inexpensively in a high yield a halogen-containing aromatic compound, particularly a halogen-containing aromatic compound incorporating therein a bromodifluoroalkyl group, and a halogen-containing naphthalene compound useful as a raw material for a resin excelling in heat resistance, chemical resistance and water repellency, and having a low dielectric constant and a low refractivity are provided. This invention relates to a method for the production of an aromatic compound (II) having a (CH2)nCX2Br group (wherein X represents a fluorine or chlorine atom and the X's may be same or different, and n is an integer in the range of 0 to 4) by the reaction of photo-bromination of an aromatic compound (I) having a (CH2)nCX2H group (wherein X and n are as defined above) with a brominating agent, wherein the photo-bromination reaction is carried out while removing hydrogen bromide generated in the reaction system and/or in an atmosphere of a low oxygen content, and a halogen-containing naphthalene compound represented by the following formula (1): wherein Y represents —CF2H, —CF2Br, or —CHO group, Z1 and Z2 independently represent a halogen atom, and p and q independently are an integer in the range of 0 to 3.

    Process for the purification of cyclopropanecarboxaldehyde
    3.
    发明授权
    Process for the purification of cyclopropanecarboxaldehyde 失效
    环丙烷甲醛纯化方法

    公开(公告)号:US06353140B1

    公开(公告)日:2002-03-05

    申请号:US09877860

    申请日:2001-06-08

    IPC分类号: C07C4700

    摘要: Disclosed is process for the treatment of cyclopropanecarboxaldehdye (CPCA) which contains crotonaldehyde impurity with a base at elevated temperature to convert the crotonaldehyde to one or more higher boiling compounds followed by distillation to recover CPCA substantially free of crotonaldehyde. This selective reaction may be combined with a distillation to purify CPCA or in combination with the reaction of the CPCA in the treated mixture to produce a CPCA-derivative while avoiding or minimizing the formation of the analogous crotonaldehyde derivative.

    摘要翻译: 公开了用于处理在高温下含有巴豆醛杂质的环丙烷甲醛(CPCA)的方法,以将巴豆醛转化为一种或多种较高沸点化合物,随后蒸馏以回收基本上不含巴豆醛的CPCA。 该选择性反应可以与蒸馏组合以纯化CPCA或与处理的混合物中CPCA的反应组合以产生CPCA衍生物,同时避免或最小化类似的巴豆醛衍生物的形成。