Patents by Inventor Kazuhiro Watari

Kazuhiro Watari 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: 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: 4049723
    Abstract: A method for separating and recovering hydroquinone which comprises distilling a by-product-containing acid-cleavage product, which is obtained by acid-cleavage of an oxidation product of para-diisopropyl benzene in a solvent, in the presence of an aromatic hydrocarbon, thereby removing low-boiling fractions including the solvent, bringing the resulting hydroquinone-containing distillation bottoms into contact with water, and crystallizing and separating hydroquinone; characterized in thatA. the distilling off of the low-boiling fractions is effected without the addition of water and in the absence of an azeotropic amount of water and also in the presence of an aromatic hydrocarbon containing 9 to 10 carbon atoms, andB. the contacting of the distillation bottoms with water is effected under conditions which do not induce crystallization of hydroquinone in the distillation bottoms.
    Type: Grant
    Filed: September 17, 1975
    Date of Patent: September 20, 1977
    Assignee: Mitsui Petrochemical Industries, Ltd.
    Inventors: Seiichi Tanaka, Kazuhiro Watari, Hideki Hayashi