Nittetsu Mining Co., Ltd.

Other

Hitachi Powdered Metals Co., Ltd.

Dowa Mining Co., Ltd.

Toyohisa Fujita

Kenji Yoshino

Takafumi Atarashi

Katsuto Nakatsuka

Kaoru Saruta

Yoshiyuki Watanabe

Young-sam Kim

Junzo Shimoiizaka

A sulfurous compound such as a sulfur-rich &ldquo;float&rdquo; (concentrate) obtained by flotation of the residue from the leaching of a zinc concentrate is heated at a temperature not lower than the melting point of sulfur but below its boiling point, preferably not higher than 200&deg; C., more preferably not higher than 140&deg; C., and the evolving gas containing sulfur vapor is cooled at a temperature less than the melting point of sulfur, preferably at ordinary temperature, to condense sulfur.

Method of recovering sulfur from minerals and other sulfur-containing compounds

A magnetic fluid and a process for producing the same are provided. The magnetic fluid is an excellent fluid which mightily and precisely actuates by the action of an external magnetic field so that its viscosity can be significantly increased and be easily and precisely controlled by regulating the external magnetic field applied thereto. The magnetic fluid is also excellent in the unsusceptibility to oxidation and dispersibility of the particles and has a sufficiently wide viscosity range. The magnetic fluid comprises magnetic metal particles coated with an oxidation-preventive film stably dispersed in a solvent, wherein the dispersion conditions are maintained, and the process for producing the fluid comprises forming an oxide film on the surface of raw oxide particles of magnetic metal particles, reducing the raw oxide particles coated with the oxide film to obtain magnetic metal particles coated with an oxidation-preventive film, and stably dispersing the magnetic metal particles coated with an oxidation-preventive film in a solvent.

Magnetic fluid and process for the production thereof

An electrorheological magnetic fluid including an electrically insulating liquid and fine particles dispersed therein is described, wherein the fine particles include a fine magnetic particle as a core, wherein the fine magnetic particle has a surface which is covered by an electroconductive substance, and the fine magnetic particle with its surface covered by the electroconductive substance is completely coated with a surfactant. A process for producing the electrorheological magnetic fluid is also described.

Electrorheological magnetic fluid and process for producing the same

Method and device of separating materials of different density by ferromagnetic liquid, using the separation zone formed by a set of magnets disposed so as to form a V-shaped gutter with both of the pole faces thereof. Objects to be separate are moved crosswise to the gutter by forming the separation zone extending in the range of the opening portion of the V-shaped gutter in such a manner that the separation zone is sloping in a plane across the gutter. This permits separation of materials of larger size in comparison with prior methods. The device is suitable for separating materials having larger size such as scraps of automobile containing aluminum and its alloys having a relatively large size and adapted to be separated from other heavy materials such as copper, zinc and their alloys.

Method and device of separating materials of different density by

Growing community of inventors

Akita, Japan

Toyohisa Fujita