Ube Industries, Inc.

Osaka University

Koji Kaiso

Toshihiro Shimakawa

Shigehiro Nishijima

Fumihito Mishima

Junichi Kugimoto

Nobuyuki Kuroda

Hirofumi Takemoto

Mitsuo Yamanaka

Tsunemi Sugimoto

Hideo Shimomura

Kohei Ninomiya

Osamu Yamazaki

Masanori Abe

The present invention is a method for applying a gradient magnetic field to a paramagnetic supporting liquid containing a mixture of first particles and second particles to separate the mixture by particle type. A magnetic susceptibility of the first particles is lower than that of the liquid, and a magnetic susceptibility of the second particles is higher than that of the liquid. A gradient magnetic field is applied to the liquid in a separation tank provided with a magnetic filter and the liquid is stirred. The first particles float in the liquid by a magneto-Archimedes effect. A horizontal magnetic force acts on the first particles by the gradient magnetic field, so that the first particles travel to a region lateral to or outward from the magnetic filter and are gathered in the region. The magnetic filter is excited by the gradient magnetic field to catch the second particles.

Method and apparatus for separation of mixture

The present invention provides a method and an apparatus for separating a mixture that are capable of separating a mixture containing a plurality types of particles, using a countercurrent classification technique, even when there is little difference in density and particle diameter depending on the types of particles. In the present invention, a mixture containing first particles and second particles is separated using a separation tubehaving the inverted-conical or pyramidal shape or a substantially inverted-conical or pyramidal shape. The first particles and the second particles are made of substances having different magnetic susceptibilities. A fluid is caused to flow upward through the separation tube, and the flow of the fluid is used to introduce the mixture into the separation tube. The first particles and the second particles are held in the separation tubein a mixed state. A gradient magnetic field is applied to a region inside the separation tubeusing magnetic field generation means, in the state where the first particles and the second particles are held in the separation tube. The magnetic field gradient of the gradient magnetic field has a vertical component.

Provided are a mixture separation method and a separation apparatus in which agglomeration of particles contained in the mixture is suppressed, energy required in distillation treatment of a supporting liquid is small in comparison with conventional methods, and particles that cannot be separated by conventional methods can be separated from a mixture containing the particles. The separation method and separation apparatus of the present invention separate, by type, a plurality of types of particles formed of mutually different materials by applying a magnetic field having a magnetic field gradient to the mixture containing the plurality of types of particles in the supporting liquid. Alternatively, the separation method and separation apparatus of the present invention separate a specific type of particle from such mixture. The supporting liquid is an organic solvent solution obtained by dissolving one or more types of paramagnetic compounds in an organic solvent. The plurality of types of particles includes particles of an inorganic salt, an organic acid salt, an inorganic oxide or a macromolecular compound. The organic solvent may be selected from the group consisting of alcohols, ethers, nitriles, ketones, esters, amides, sulfoxides, halomethanes and hydrocarbon solvents.

There is provided a novel polyamide particles having an approximately spherical outer shape, which are spongy particles having through-holes in an outer surface part and closed voids in an inside part. The polyamide particles can be produced by dissolving a polyamide in a cyclic amide with heating to obtain a homogeneous solution and then cooling the solution.

Polyamide particles and process for producing same

1,2-epoxy-5,9-cyclododecadiene is produced with a high selectivity thereto by epoxidizing 1,5,9-cyclododecatriene in a continuous multi-stage oxidation apparatus having a plurality of reactors connected to each other in series in such a manner that (1) in a first reactor, 1,5,9-cyclododecatriene, hydrogen peroxide, catalyst components and optionally a mineral acid are subjected to an epoxidation reaction; (2) the resultant reaction mixture delivered from the first reactor is passed through one or more succeeding reactors to further epoxidize the non-reacted 1,5,9-cyclododecatriene with the non-reacted hydrogen peroxide; and (3) the final reaction mixture produced in a rearend reactor is delivered from the oxidation apparatus, and optionally subjected to an isolation-refining procedure wherein the target 1,2-epoxy-5,9-cyclododecadiene is refined and collected and the non-reacted 1,5,9-cyclododecatriene is recovered and recycled to the epoxidation procedure.

Growing community of inventors

Yamaguchi, Japan

Koji Kaiso