3.
    发明专利
    未知

    公开(公告)号:DE2430757A1

    公开(公告)日:1975-01-23

    申请号:DE2430757

    申请日:1974-06-26

    Applicant: STAMICARBON

    Abstract: epsilon -CAPROLACTAM IS RECOVERED FROM A Beckmann rearrangement mixture of the lactam and aqueous sulfuric acid by simultaneously neutralizing the rearrangement mixture with ammonia at a pressure of 1-5 atmospheres and crystallizing out ammonium sulfate, the heat liberated by the neutralization reaction is removed from the system by evaporating a portion of the water from the solution. At the conditions employed hydrolysis of the lactam is substantially reduced if not entirely avoided.

    4.
    发明专利
    未知

    公开(公告)号:DE1493198A1

    公开(公告)日:1969-02-27

    申请号:DE1493198

    申请日:1964-11-26

    Applicant: STAMICARBON

    Abstract: Oximes are prepared by reacting an aqueous solution of a hydroxylamine salt with an aliphatic, alicyclic or aromatic aldehyde or ketone in the presence, either at the beginning of the reaction or after the reaction has started, of both a weak acid having a dissociation constant of 2 x 10-1 to 10-6 at 25 DEG C., and at least one soluble salt thereof in such a ratio that the pH of the reaction mixture during the first and greater part of the reaction is in the range 1-4, recovering the oxime and separating the dissolved salt from the acid liberated during the reaction. Specified weak acids are ammonium bisulphate, phosphoric, formic, acetic, lactic, citric and benzenesulphonic acids. It is preferred to use a hydroxylamine salt derived from the weak acid, and to use the acid recovered from the reaction mixture to form further hydroxylamine salt starting material. To effect complete conversion to the oxime to pH of the reaction mixture during the last part of the reaction is raised to a value greater than 4, e.g. by adding ammonia. The process is illustrated by referceen to flow diagrams (not shown).

    6.
    发明专利
    未知

    公开(公告)号:DE2129657A1

    公开(公告)日:1971-12-23

    申请号:DE2129657

    申请日:1971-06-15

    Applicant: STAMICARBON

    Abstract: 1313959 Phosphoric acid; ammonium phosphate STAMICARBON NV 15 June 1971 [17 June 1970] 28034/71 Heading C1A [Also in Division C2] The decomposition of rock phosphate is carried out using the solution remaining after removal of the lactam from a mixture thereof with sulphuric acid and/or free SO 3 by adding an aqueous solution of ammonium or alkali metal dihydrogen phosphate in a molar ratio of phosphate to sulphuric acid and/or free SO 3 of at least 0À25 : 1 and extracting the lactam by means of an extraction agent. The free phosphoric acid-containing solution remaining after the decomposition of the rock phosphate is treated to remove gypsum therefrom and at least a portion of the solution is neutralized to form ammonium dihydrogen phosphate which may be recycled to the lactam removal zone.

    7.
    发明专利
    未知

    公开(公告)号:DE2222216A1

    公开(公告)日:1972-11-23

    申请号:DE2222216

    申请日:1972-05-05

    Applicant: STAMICARBON

    Abstract: A process for preparing and recovering lactams by the so-called Beckmann rearrangement of the corresponding ketoximes in a sulfuric acid medium is disclosed, wherein the mixture of lactam and sulfuric acid medium obtained from the Beckmann rearrangement is mixed with an aqueous solution of ammonium sulfate obtained as a by-product in the synthesis of hydroxylammonium sulfate in the preparation of said ketoximes. The lactam is then extracted from the resulting less acidic solution and the remaining acid solution, comprising an aqueous solution of ammonium hydrogen sulfate, is thermally decomposed to produce recoverable sulphur dioxide.

    9.
    发明专利
    未知

    公开(公告)号:DE2129658A1

    公开(公告)日:1971-12-23

    申请号:DE2129658

    申请日:1971-06-15

    Applicant: STAMICARBON

    Abstract: A process for synthesizing an oxime by reacting an organic carbonyl compound with a hydroxylammonium sulfate and ammonium hydrogen sulfate in the presence of ammonium dihydrogen phosphate whereby an aqueous solution of phosphoric acid and ammonium sulfate is obtained after separating the oxime product therefrom. The phosphoric acid, ammonium sulfate solution can be used in processing rock phosphate with the aid of nitric acid to product a fertilizer composition having a N to P2O5 ratio of approximately 1:1.

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