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    4.
    发明专利
    未知

    公开(公告)号：DE1263722B

    公开(公告)日：1968-03-21

    申请号：DEST022773

    申请日：1964-10-05

    Applicant: STAMICARBON

    Inventor： ROOIJ ABRAHAM HERMANUS DE ,  ELMENDORP JAN

    IPC: C01B21/46 ,  C01B25/22 ,  C01B25/234

    Abstract: An aqueous solution containing both phosphoric and nitric acids is extracted with a poorly water-miscible aliphatic ketone or ether having from 4 to 13 carbon atoms, the concentration of the starting solution and the weight ratio of the starting solution to the extracting agent being selected so that at least 90% of the nitric acid but not more than 10% of the phosphoric acid passes into the organic phase. The starting solution preferably contains at least 40%, but not more than 75%, by weight of water. When the starting solution contains from 40% to 70% by weight of water, the weight ratio between the acid solution and the ketone or ether preferably is kept at from 1: 1 to 1: 3, a higher proportion of extracting agent being favoured for more dilute solutions. The extraction either may be performed batchwise in one or a plurality of stages or may be carried out continuously with countercurrent flow of extracting agent and acid solution. The ketone or ether may be diethyl ether, diisopropyl ether, dibutyl ether, diisoamyl ether, methyl-isobutyl ketone, methyl-isoamyl ketone, butyl-ethyl ketone, diisobutyl ketone or dibutyl carbitol; the preferred extracting agent is methyl-isobutyl ketone. The above separation process may be applied in the recovery of phosphoric acid from the liquor resulting from the decomposition of phosphate rock by concentrated nitric acid. Such a procedure, an example of which is fully described and illustrated in the Specification, may entail preparing an aqueous solution of phosphoric and nitric acids by decomposing phosphate rock with nitric acid having a concentration of at least 45% by weight acid, lowering the molar calcium oxide/phosphorus pentoxide ratio of the solution to below 1.5 by cooling to remove calcium nitrate, subjecting the solution to an extraction with a butyl or amyl alcohol, freeing the resulting acids-containing organic extract from residual calcium nitrate by washing with a solution containing phosphoric acid and possibly nitric acid and having a concentration of at least 25% by weight total acid(s), washing the acid-washed organic extract with water in an amount such that not more than three quarters of the total acids present passes from the organic extract to the water, and separating the phosphoric acid from the nitric acid in the resulting aqueous acid solution by the extraction process described previously.

    RECOVERY OF EPSILON-CAPROLACTAM
    5.
    发明专利
    RECOVERY OF EPSILON-CAPROLACTAM 未知

    公开(公告)号：AU7072774A

    公开(公告)日：1976-01-08

    申请号：AU7072774

    申请日：1974-07-02

    Applicant: STAMICARBON

    Inventor： ROOIJ ABRAHAM HERMANUS DE ,  ELMENDORP JAN

    IPC: C01C1/24 ,  C01C1/242 ,  C05C3/00 ,  C07D201/16 ,  C07D41/06

    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.

    6.
    发明专利
    未知

    公开(公告)号：DE2260014A1

    公开(公告)日：1973-06-14

    申请号：DE2260014

    申请日：1972-12-07

    Applicant: STAMICARBON

    Inventor： ROOIJ ABRAHAM HERMANUS DE ,  GOETTSCH REIJER

    IPC: B01D11/04 ,  B01D9/02 ,  C07D201/04 ,  C07D201/16 ,  C07D41/06

    Abstract: A process for recovering lactams from a mixture of one or more lactams and sulphuric acid is disclosed, wherein the sulphuric acid is neutralized with ammonia or an ammonium salt to ammonium hydrogen sulfate in the presence of a lactam solvent. The neutralization produces a melt of ammonium hydrogen sulfate and a solution of lactam in the organic solvent, and the melt is readily separated from the solution. The lactam can then be recovered from the organic solvent.

    7.
    发明专利
    未知

    公开(公告)号：DE1271711B

    公开(公告)日：1968-07-04

    申请号：DEST023159

    申请日：1964-12-30

    Applicant: STAMICARBON

    Inventor： ROOIJ ABRAHAM HERMANUS DE

    IPC: C07D201/06

    Abstract: Oximes are prepared by reacting carbonyl compounds with hydroxylammonium sulphate solution, obtained by reducing SO2 with nitritebisulphite solution, which contains such an amount of ammonium sulphate that during the reaction the medium is buffered at pH 1.5-3. The preparation of cyclohexanone oxime is exemplified.

    8.
    发明专利
    未知

    公开(公告)号：DE1242194B

    公开(公告)日：1967-06-15

    申请号：DEST020360

    申请日：1963-03-01

    Applicant: STAMICARBON

    Inventor： ROOIJ ABRAHAM HERMANUS DE

    IPC: C01B21/086 ,  C01B21/094

    Abstract: A nitrosating acid, i.e. a solution of nitrosylsulphuric acid in sulphuric acid, is prepared by absorbing nitrous gases, i.e. NO and NO2, in a solution of nitrosylsulphuric acid in sulphuric acid, to which solution, SO3 either in the form of gaseous SO3 and water and/or sulphuric acid, or in the form of oleum, is supplied for replenishing or maintaining the sulphuric acid content of said solution. The process may be a batch or continuous process. The degree of oxidation of the nitrous gases should preferably be at least 0.5, i.e. the gases preferably contain an amount of NO which is at least equal to the amount of NO2. The temperature of the absorbent acid is preferably maintained between 0 DEG and 40 DEG C. When the process is carried out continuously by means of a circulating amount of absorbent acid, the composition of the absorbent acid should be approximately equal to that of the nitrosating acid to be prepared. The ratio between the components NOHSO4, H2SO4 and SO3 can be widely varied, and is determined only by the requirement that the absorbent acid must be liquid in the temperature range in which the absorption takes place. In Fig. 1 (not shown), the absorbent acid, i.e. nitrosylsulphuric acid dissolved in sulphuric acid, circulates through the absorption column 1, via cooler 2, pump 3 and conduit 4. Nitrous gases enter through 5 and non-absorbed gases escape through 6. Part of the circulating absorbent acid passes to mixing vessel 9, via conduit 7. Oleum passes to vessel 9 from vessel 10 via conduit 11. Cooling spiral 18 maintains a uniform temperature in vessel 9. Part of the contents of vessel 9 are fed to column 1 via pump 13 and conduit 14, the remainder being collected as produced nitrosating acid in reservoir 19 via conduit 15. Valves 8, 16 and 17 control the amounts of liquid passing through conduits 7, 11 and 15. This ensures that a solution of nitrosyl sulphuric acid in free SO3-containing sulphuric acid is passed through column 1. Fig. 2 (not shown) concerns a modification of the process employed in Fig. 1 wherein no oleum is employed, SO3-containing contact gas being fed into a second absorption column, which takes over the function of the mixing vessel 9 in Fig. 1.

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