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    Production of maleic anhydride
    1.
    发明专利
    Production of maleic anhydride 未知

    公开(公告)号：GB1007742A

    公开(公告)日：1965-10-22

    申请号：GB3107162

    申请日：1962-08-14

    Applicant: BASF AG

    Inventor： SCHLIESSER WALTER ,  SUTER HUBERT

    Abstract: Maleic anhydride is prepared by contacting maleic acid, or a mixture of maleic and phthalic acids, at a temperature of from 200 DEG to 450 DEG C., in a reaction zone, with moving particles of a dehydration catalyst of particle size of 0.05 to 0.5 mm., condensing from the gases leaving the reaction zone the anhydrides by cooling, and separating the maleic anhydride. The catalyst may be any solid dehydration catalyst for example, borates, phosphates, alumina, silica gel, titanium dioxide, zirconium dioxide, thorium oxide and mixtures thereof, which may be supported on a carrier which may be inert, e.g. pumice, aluminium silicate or silicon carbide, or may be active, e.g. silica gel. The catalyst is preferably used as a fluidized bed formed by a stream of inert gas or alternatively may be allowed to flow through the reaction chamber from top to bottom with continuous circulation without creating a fluidized bed. The reaction chamber may be heated by direct external heating or by using inert gases which have been preheated to, for example, 220-450 DEG C. The starting material, which may be pure or technical grade maleic acid or a mixture of maleic and phthalic acids obtained by, for example, oxidation of o-dialkyl benzenes, is fed to the reaction chamber in a molten or powdered state, preferably with the aid of a gas stream. When using a melt it is advantageous to atomize the liquid through a nozzle. A powder is preferably added at room temperature, or slightly above, e.g. 80-90 DEG C. The reaction is preferably carried out at 220-300 DEG C. at pressures of, for example, 200 mm. Hg to 5 atmospheres, preferably at ordinary pressure for a residence time of 0.5 to 20 secs. When the starting material consists essentially of maleic acid, for example 98% maleic acid, a residence time of 0.5 to 1 sec. may be used. With a large proportion of phthalic acid, residence times of up to 10 secs. may be required. All the reaction product may be condensed, but it is preferably to cool the products to 1 DEG to 5 DEG C. above the dew point of the water present to prevent the condensation of water. When a large amount of phthalic anhydride is present, e.g. above 90%, it is preferable to carry out a fractional condensation, initially at 130-135 DEG C. to give nearly pure phthalic anhydride followed by cooling to just above the dew point of water to give a mixture of maleic and phthalic anhydrides. The maleic anhydride, which is free of fumaric acid, may be purified by fractional distillation. The outgoing gases from the condensation may be washed with water to give a solution of maleic and phthalic acids which on removal of water may be recycled.

    Production of acrylic acid compounds
    2.
    发明专利
    Production of acrylic acid compounds 未知

    公开(公告)号：GB935051A

    公开(公告)日：1963-08-28

    申请号：GB1157662

    申请日：1962-03-27

    Applicant: BASF AG

    Inventor： SCHWECKENDIEK WALTER ,  SCHLIESSER WALTER

    IPC: C07C69/54

    Abstract: Acrylic acid compounds of the general formula CHR1=CR2-COX in which R1 is hydrogen or a methyl group, R2 is hydrogen or a methyl group, X is an alcohol, mercaptan or secondary amine radical attached through the hetero atom, are produced by heating at between 60 DEG and 500 DEG C. an ethylenedicarboxylic acid derivative of formula with a tertiary phosphine, tertiary arsine or tertiary stibine as catalyst. When carried out in the liquid phase, the temperature is preferably between 80 DEG and 260 DEG C. A metal, metal oxide, metal hydroxide, metal sulphide, or metal salt may be used as activator. A tertiary phosphine may be used in admixture with one or more of a tertiary arsine or stibine, the mole ratio of phosphine to the other tertiary component or components being between 1 : 0,1 and 1 : 0,5. The catalyst may be applied to a porous support. A nonreactive gas may be introduced into the reaction mixture during the reaction to carry off the products formed. Alternatively, the initial material may be dissolved in a low-boiling solvent prior to its addition to the catalyst. Numerous examples of initial materials, catalysts, and activators are given.

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