Patents by Inventor Hirohiko Nambu

Hirohiko Nambu has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4355190
    Abstract: A process for recovery of resorcinol from an aqueous resorcinol solution containing hydroquinone which comprises oxidizing an aqueous resorcinol solution containing about 10 to about 60% by weight of resorcinol and up to about 1% by weight of hydroquinone with molecular oxygen at conditions of pH 6.5 to 9.5, followed by recovering resorcinol from the resultant oxidation product.
    Type: Grant
    Filed: December 10, 1980
    Date of Patent: October 19, 1982
    Assignee: Mitsui Petrochemical Industries, Ltd.
    Inventors: Hirohiko Nambu, Fujihisa Matsunaga, Hiroaki Nakagawa
  • Patent number: 4334108
    Abstract: Disclosed is a process for the preparation of phenols which comprises reacting an .alpha.-hydroxyalkyl-substituted aromatic compound and/or an .alpha.,.beta.-unsaturated alkyl-substituted aromatic compound with hydrogen peroxide in the presence of an acid catalyst, in which hydrogen peroxide is diluted with a diluent, especially acetone, so that the volume is at least 10 times the original volume, and the diluted hydrogen peroxide is supplied in a divided manner to at least two portions of a reaction vessel or the diluted hydrogen peroxide is scattered by sprinkling into the reaction vessel. According to a preferred embodiment, the diluted hydrogen peroxide is continuously supplied to the gas phase in the reaction vessel from a scattering device which is similar to but separate from a scattering device for supplying the starting aromatic compound, particularly, a product formed by oxidizing an isopropyl aromatic compound with molecular oxygen.
    Type: Grant
    Filed: June 30, 1980
    Date of Patent: June 8, 1982
    Assignee: Mitsu Petrochemical Industries Ltd.
    Inventors: Katsuhiko Hashimoto, Hirohiko Nambu, Kazuhiro Watari, Kenichi Mizuno, Tadateru Murakami, Yutaka Matsuoka, Mitsutoshi Moriyama, Norio Ohno
  • Patent number: 4323505
    Abstract: A compound of the formula (I) ##STR1## wherein R.sup.1 and R.sup.5 each represents an alkyl group having 1 to 3 carbon atoms; R.sup.2, R.sup.3 and R.sup.4 each represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms and wherein the bonding at the 2-3 position is a single bond and that at the 3-4 position is a double when the substitution of hydroxy group is at the 5-position or the bonding at the 2-3 position is a double bond and that at the 3-4 position is a single bond when the substitution of hydroxy group is at the 7-position; with the proviso that R.sup.2 and R.sup.4 should not be a hydrogen atom or an alkyl group simultaneously and process for preparing same are disclosed. The compound is useful as a herbicide and fungicide and as an intermediate for preparing agricultural chemicals, etc.
    Type: Grant
    Filed: June 27, 1980
    Date of Patent: April 6, 1982
    Assignee: Mitsui Petrochemical Industries, Ltd.
    Inventors: Isao Hashimoto, Hirohiko Nambu
  • Patent number: 4322567
    Abstract: In a process for producing an aromatic alcohol by catalytic hydrogenation of at least one tertiary peroxide selected from the group consisting of tertiary aromatic hydroperoxides and tertiary aromatic peroxides in the presence of a palladium catalyst in a lower aliphatic alcohol solvent to form the corresponding alcohol; the improvement wherein said catalyst has a palladium metal surface area, determined by the CO chemisorption method, of up to about 200 m.sup.2 /g.multidot.Pd.
    Type: Grant
    Filed: May 22, 1980
    Date of Patent: March 30, 1982
    Assignee: Mitsui Petrochemical Industries Ltd.
    Inventors: Fujihisa Matsunaga, Norio Ohno, Hirohiko Nambu
  • Patent number: 4283567
    Abstract: In a method for recovering resorcinol by thermally cracking high-boiling by-products formed by the acid-cleavage of m-diisopropylbenzene dihydroperoxide in the presence of at least one ammonium compound selected from the group consisting of ammonium sulfate and ammonium bisulfate at a temperature of about 170.degree. C. to about 350.degree. C. under reduced pressure, the improvement wherein said thermal cracking is carried out at a pressure of less than 50 mmHg gauge in the absence of any inert gas supplied.
    Type: Grant
    Filed: December 19, 1979
    Date of Patent: August 11, 1981
    Assignee: Mitsui Petrochemical Industries Ltd.
    Inventors: Hirohiko Nambu, Hiroaki Nakagawa, Masayasu Isibasi
  • Patent number: 4273623
    Abstract: In the process for obtaining a concentrate of resorcin by acid-decomposing m-diisopropylbenzene hydroperoxide in an inert solvent in the presence of an acidic solid catalyst and distilling off acetone and the inert solvent from the resulting acid-decomposition reaction mixture, if water is added to this reaction mixture in an amount of 20 to 70% by weight based on resorcin and the reaction mixture is then subjected to distillation, resorcin can be obtained at a high recovery yield.
    Type: Grant
    Filed: May 22, 1979
    Date of Patent: June 16, 1981
    Assignee: Mitsui Petrochemical Industries, Ltd.
    Inventors: Isao Hashimoto, Toru Taguchi, Hirohiko Nambu
  • Patent number: 4271322
    Abstract: Disclosed is a process for the preparation of phenols which comprises the steps of (I) decomposing a hydroperoxide of an isopropyl aromatic compound with an acid catalyst, (II) separating the decomposition product obtained in step (I) into acetone, phenols, hydrocarbons and distillation residue by distillation of the decomposition product and (III) thermally decomposing the distillation residue and recycling the resulting crude phenol to step (II), wherein the crude phenol obtained in step (III) is contacted with a glycol to form a hydrocarbon layer and an extract layer comprising the glycol and phenol, and the phenol in said extract layer is recycled to step (II).According to this process, mingling of impurity components having a boiling point close to that of the desired phenol, which are contained in the thermal decomposition product of the distillation residue, into the product phenol can be effectively prevented, and the desired phenol can be obtained at a high purity and at a high recovery yield.
    Type: Grant
    Filed: January 3, 1980
    Date of Patent: June 2, 1981
    Assignee: Mitsui Petrochemical Industries, Ltd.
    Inventors: Fujihisa Matsunaga, Hirohiko Nambu
  • Patent number: 4266081
    Abstract: A process for the preparation of peroxides by condensation reaction of a tertiary organic hydroperoxide with a tertiary alcohol, which is characterized in that zinc chloride is present as a catalyst in an amount of at least 1% by weight based on the tertiary alcohol, is disclosed. This process can be advantageously applied to continuous manufacture of peroxides, and according to this process, peroxides can be obtained in high yields.
    Type: Grant
    Filed: September 21, 1978
    Date of Patent: May 5, 1981
    Assignee: Mitsui Petrochemical Industries Ltd.
    Inventors: Kenichi Mizuno, Hiroshi Iwasaki, Hirohiko Nambu
  • Patent number: 4239644
    Abstract: A liquid peroxide composition comprising dicumyl peroxide and a dicumyl peroxide derivative having one nucleus substituted by an alkyl group having 1 to 3 carbon atoms is disclosed. This peroxide composition can easily be handled because it is liquid, and it is very valuable as a cross-linking agent for an olefin polymer or a synthetic rubber.
    Type: Grant
    Filed: March 21, 1979
    Date of Patent: December 16, 1980
    Assignee: Mitsui Petrochemical Industries Ltd.
    Inventors: Hirohiko Nambu, Kenichi Mizuno, Tetuhiro Matumoto
  • Patent number: 4239921
    Abstract: In a process for purification of crude resorcinol derived from an acid-cleavage product of m-diisopropylbenzene dihydroperoxide and containing impurities having higher boiling points than resorcinol is, the recrystallization of said crude resorcinol from a mixed solvent consisting of(a) about 0.5 to about 5 times the weight of resorcinol of an aromatic hydrocarbon which contains 6 to 10 carbon atoms and is liquid at 20.degree. C., and(b) about 0.1 to about 0.7 time the weight of resorcinol of at least one compound selected from the group consisting of alkyl phenols having a C.sub.1 -C.sub.4 alkyl group and acyl phenols derived from C.sub.2 -C.sub.4 aliphatic monocarboxylic acids.
    Type: Grant
    Filed: July 10, 1979
    Date of Patent: December 16, 1980
    Assignee: Mitsu, Petrochemical Industries, Ltd.
    Inventors: Isao Hashimoto, Hiroaki Nakagawa, Toru Taguchi, Hirohiko Nambu
  • Patent number: 4237319
    Abstract: A process for producing m-diisopropylbenzene dihydroperoxide which comprises oxidizing m-diisopropylbenzene in the liquid phase with molecular oxygen under alkaline conditions; wherein the oxidation is carried out under conditions (A), (B) and (C) below,(A) under conditions which meet (i), (ii), (iii) and (iv) below,(i) 0.ltoreq.x.ltoreq.140(ii) y.gtoreq.80(iii) -0.05x+110.gtoreq.y.gtoreq.-0.15x+95wherein 0.ltoreq.x.ltoreq.100(iv) y.ltoreq.-0.25x+130wherein 100<x.ltoreq.140in which x represents the absolute value of the concentration of hydroperoxides in the oxidation product in % by weight calculated as m-diisopropylbenzene monohydroperoxide, and y represents the absolute value of the reaction temperature in degrees centigrade,(B) until x reaches at least 120, and(C) so that the reaction temperature at 100<x.ltoreq.140 is lower than the reaction temperature at the start of the reaction (x=0).
    Type: Grant
    Filed: October 24, 1978
    Date of Patent: December 2, 1980
    Assignee: Mitsui Petrochemical Industries Ltd.
    Inventors: Hirohiko Nambu, Isao Hashimoto, Ichiro Imai
  • Patent number: 4192958
    Abstract: A method for recovering resorcinol by thermally cracking high-boiling by-products contained in the acid-cleavage product of m-diisopropylbenzene dihydroperoxide, wherein the thermal cracking is effected in the presence of an aromatic ketone of the formula ##STR1## wherein R.sup.1 represents a member selected from the group consisting of hydrogen, saturated alkyl groups having 1 to 6 carbon atoms, hydroxyl, acetyl and chlorine, R.sup.2 represents a member selected from the group consisting of saturated alkyl groups having 1 to 6 carbon atoms, cyclohexyl and phenyl, and n represents 1, 2 or 3, and when there are two or more R.sup.1 groups, they are identical or different.
    Type: Grant
    Filed: September 26, 1978
    Date of Patent: March 11, 1980
    Assignee: Mitsui Petrochemical Industries Ltd.
    Inventors: Isao Hashimoto, Hiroaki Nakagawa, Hirohiko Nambu
  • Patent number: 4154967
    Abstract: A process for producing phenols which comprises oxidizing an aromatic hydrocarbon ring-substituted by an isopropyl group in one step in the liquid phase using molecular oxygen or a gas containing molecular oxygen in the presence or absence of a solvent, wherein the oxidation is carried out in the presence of an aromatic mercaptan having an acid dissociation constant (pKa) of less than 7.8.
    Type: Grant
    Filed: May 6, 1977
    Date of Patent: May 15, 1979
    Assignee: Mitsui Petrochemical Industries, Ltd.
    Inventors: Fujihisa Matsunaga, Hirohiko Nambu