REDUCTION OF OXIDANT BY OPERATION AND/OR TREATMENT OF AQUEOUS ACRYLONITRILE PROCESS STREAM

    公开(公告)号:JPH11322696A

    公开(公告)日:1999-11-24

    申请号:JP33815698

    申请日:1998-11-27

    Abstract: PROBLEM TO BE SOLVED: To obtain a specific unsaturated mononitrile useful as a monomer for a polymerizing reaction without contamination with an impurity by reacting a specific olefin, ammonia, etc., in the presence of a catalyst, reducing the pH of an aqueous stream used till the recovery and purification before recycling and then reducing the amount of the trace impurity. SOLUTION: An olefin selected from propylene and isobutylene is reacted with ammonia and oxygen in the presence of a catalyst in a reactor zone. A reactor effluent containing the produced unsaturated mononitrile from the reactor is then brought into contact with at least a first aqueous stream in a quenching column and cooled. The cooled reactor effluent is subsequently brought into contact with at least a second aqueous stream in an absorption column to separate and remove a bottom stream containing the unsaturated mononitrile. The resultant bottom stream is then moved to a recovery and purification section and the pH of at least one aqueous process stream is reduced before recycling to thereby reduce the amount of a trace impurity. The resultant bottom stream is further recycled to afford the objective compound selected from acrylonitrile and methacrylonitrile.

    OXIDANT REDUCTION BY MANIPULATION AND/OR TREATMENT OF AQUEOUS ACRYLONITRILE PROCESS STREAMS

    公开(公告)号:BG102955A

    公开(公告)日:2000-04-28

    申请号:BG10295598

    申请日:1998-11-26

    Abstract: The invention relates to a method for the manufacturing of unsaturated mononitrile from the group of acrylonitrile and methacrylonitrile. It includes reaction of olefine from the group containing propylene or isobutylene and ammonia and oxygen in a reaction zone in the presence of a catalyst to produce a reactor effluent containing the corresponding unsaturated mononitrile. The effluent runs over a cooling column where, in order to cool, it gets into contact with at least first aqueous stream. The cooled reactor effluent containing the unsaturated mononitrile is transferred into an absorption column where it is contacted with at least a second aqueous stream to separate and remove the unsaturated mononitrile as a bottom stream from the absorption column. The bottom stream containing the unsaturated mononitrile is transferred to a recovery and purification section where the unsaturated mononitrile is recovered and purified. At least one aqueous process stream is recirculated for improving the efficiency of the process consisting in reducing the pH, thereby reducing the amount of trace impurities in the aqueous recirculation stream. 8 claims, 1 figure

    4.
    发明专利
    未知

    公开(公告)号:BR9805434A

    公开(公告)日:1999-12-14

    申请号:BR9805434

    申请日:1998-11-26

    Abstract: A process for manufacturing an unsaturated mononitrile selected from the group consisting of acrylonitrile and methacrylonitrile comprising reacting an olefin selected from the group consisting of propylene and isobutylene, ammonia and oxygen in a reactor zone in the presence of a catalyst to produce a reactor effluent containing the corresponding unsaturated mononitrile, transferring the reactor effluent containing the unsaturated mononitrile to a quench column wherein the reactor effluent containing the unsaturated mononitrile is contacted with at least a first aqueous stream to cool the reactor effluent, transferring the cooled reactor effluent containing the unsaturated mononitrile to an absorption column wherein the reactor effluent containing unsaturated mononitrile is contacted with at least a second aqueous stream to separate and remove the unsaturated mononitrile as a bottom stream from the absorption column, transferring the bottom stream containing the unsaturated mononitrile to a recovery and purification section where the unsaturated mononitrile is recovered and purified, and recycling at least one aqueous process stream to improve the efficiency of the process wherein the improvement comprises treating at least one aqueous stream before recycling into the process stream to reduce the pH thereby reducing the amount of trace impurities present in the aqueous recycle stream.

    Oxidant reduction by manipulation and/or treatment of aqueous acrylonitrile process streams

    公开(公告)号:ZA9810259B

    公开(公告)日:1999-05-18

    申请号:ZA9810259

    申请日:1998-11-10

    Abstract: A process for manufacturing an unsaturated mononitrile selected from the group consisting of acrylonitrile and methacrylonitrile comprising reacting an olefin selected from the group consisting of propylene and isobutylene, ammonia and oxygen in a reactor zone in the presence of a catalyst to produce a reactor effluent containing the corresponding unsaturated mononitrile, transferring the reactor effluent containing the unsaturated mononitrile to a quench column wherein the reactor effluent containing the unsaturated mononitrile is contacted with at least a first aqueous stream to cool the reactor effluent, transferring the cooled reactor effluent containing the unsaturated mononitrile to an absorption column wherein the reactor effluent containing unsaturated mononitrile is contacted with at least a second aqueous stream to separate and remove the unsaturated mononitrile as a bottom stream from the absorption column, transferring the bottom stream containing the unsaturated mononitrile to a recovery and purification section where the unsaturated mononitrile is recovered and purified, and recycling at least one aqueous process stream to improve the efficiency of the process wherein the improvement comprises treating at least one aqueous stream before recycling into the process stream to reduce the pH thereby reducing the amount of trace impurities present in the aqueous recycle stream.

    UPGRADING SYNTHESIS GAS
    6.
    发明专利

    公开(公告)号:CA1195678A

    公开(公告)日:1985-10-22

    申请号:CA416328

    申请日:1982-11-25

    Abstract: A process is provided for the upgrading of synthesis gas to hydrocarbons and oxygenated hydrocarbons, particularly olefins and carboxylic acids by contacting synthesis gas with catalysts comprising the mixed oxides of ruthenium, copper, an alkali or alkaline earth metal, and optionally a metal selected from Ce, Cr, Fe, Mn, Mo, Th, Zn or mixtures thereof. The synthesis gas upgrading product may be contacted with a hydrogenation catalyst to provide alkanes, alcohols and esters, useful for fuels. Catalysts comprising the mixed oxides of ruthenium, copper, at least one alkali metal and at least one of rhodium, iridium, palladium, and platinum are further provided which are useful in the upgrading of synthesis gas, particularly for obtaining alkanes and alcohols.

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