Abstract: It is an object to provide a method and an apparatus for recovering indium, the method and apparatus ensuring that it is unnecessary to recover indium in the form of indium hydroxide, indium can be recovered easily by a filter or the like without handling inferiors and also, the recovery rate of indium is greatly improved. The method includes immersing a precipitation-inducing metal which includes zinc and is made into the form of a solid such that any part coming into view three-dimensionally has a longitudinal length of 2.5 to 10 mm in an etching waste solution containing at least indium and ferric chloride and allowed to stand, thereby allowing indium contained in the etching waste solution to precipitate on the surface of the precipitation-inducing metal based on a difference in ionization tendency between zinc and indium, and detaching the indium precipitated on the surface of the precipitation-inducing metal to recover it.

Abstract: An object is to provide a method and an apparatus for recovering indium, the method and apparatus ensuring that it is unnecessary to recover indium in the form of indium hydroxide, indium can be recovered at a high concentration, indium can be recovered easily by a filter or the like without handling inferiors and also, the recovery rate of indium is greatly improved. The method includes adding a precipitation-inducing metal including a metal having higher ionization tendency than indium to an etching waste solution containing at least indium and ferric chloride, in which the concentration of ferric chloride is adjusted to 20% by weight or less to thereby precipitate indium contained in the etching waste solution on the surface of the precipitation-inducing metal, then, detaching the indium precipitated on the precipitation-inducing metal from the precipitation-inducing metal by a detaching means and separating the detached solid indium or indium alloy from the solution to recover the indium.

Abstract: It is an object to provide a method and an apparatus for recovering indium, the method and apparatus ensuring that it is unnecessary to recover indium in the form of indium hydroxide, indium can be recovered easily by a filter or the like without handling inferiors and also, the recovery rate of indium is greatly improved. The method includes immersing a precipitation-inducing metal which includes zinc and is made into the form of a solid such that any part coming into view three-dimensionally has a longitudinal length of 2.5 to 10 mm in an etching waste solution containing at least indium and ferric chloride and allowed to stand, thereby allowing indium contained in the etching waste solution to precipitate on the surface of the precipitation-inducing metal based on a difference in ionization tendency between zinc and indium, and detaching the indium precipitated on the surface of the precipitation-inducing metal to recover it.

Abstract: A hydrogen combustion device includes a casing 30, a hydrogen source, a hydrogen pipe 39 to supply hydrogen gas from the hydrogen source into the casing 30, a mixer 10 on the downstream side of the pipe 39, for stirring a mixed gas and a combustion catalyst 20. The hydrogen pipe 39 has a hydrogen pipe body 40 and a hydrogen ejecting part 41 with hydrogen ejecting orifices 42. In the hydrogen combustion device, the hydrogen ejecting part 41 is positioned at a substantial center in the cross section of an air passage in the casing 30, extending along the flowing direction of the airflow in the air passage. The hydrogen ejecting orifices 40 are arranged so that their axes extend in the radial direction of the hydrogen ejecting part 41, substantially perpendicularly to the flowing direction of the airflow.

Abstract: The invention relates to a hydrogen combustion heater. This heater includes (a) a passage for allowing hydrogen gas and air to flow therethrough; (b) a first catalyst provided in the passage, the first catalyst being heated, when electricity is applied thereto, thereby starting a first combustion of a first mixture of the hydrogen gas and the air in the first catalyst; and (c) a heat exchanger provided downstream of the first catalyst in the passage, the heat exchanger being adapted to transfer heat generated by the first combustion to a heating medium of the heat exchanger.

Abstract: A metal carrier includes a core (3) having a thinned film containing a metal catalyst. The core includes a first metal sheet (1) corrugated and having a crest with a first radius (R). The core includes a second metal sheet (2) flattened or corrugated smaller in corrugation height than the first metal sheet, The first and second metal sheets are stacked on each other to be wound up. The crest and second metal sheet are joined to each other, having a joint therebetween. A fillet of the catalyst is formed between the joint, the first metal sheet, and the second metal sheet, having an arced surface of a second radius (r) extending between the first and second metal sheets. The first radius is set substantially equal to the second radius.

Abstract: The invention relates to a hydrogen combustion heater. This heater includes (a) a passage for allowing hydrogen gas and air to flow therethrough; (b) a first catalyst provided in the passage, the first catalyst being heated, when electricity is applied thereto, thereby starting a first combustion of a first mixture of the hydrogen gas and the air in the first catalyst; and (c) a heat exchanger provided downstream of the first catalyst in the passage, the heat exchanger being adapted to transfer heat generated by the first combustion to a heating medium of the heat exchanger.

Abstract: The invention relates to a hydrogen combustion heater. This heater includes (a) a passage for allowing hydrogen gas and air to flow therethrough; (b) a first catalyst provided in the passage, the first catalyst being heated, when electricity is applied thereto, thereby starting a first combustion of a first mixture of the hydrogen gas and the air in the first catalyst; and (c) a heat exchanger provided downstream of the first catalyst in the passage, the heat exchanger being adapted to transfer heat generated by the first combustion to a heating medium of the heat exchanger.

Abstract: This invention relates to a method for producing a metallic catalyst carrier used for a catalytic convertor for an automobile, for example, and calcines a metallic catalyst carrier element obtained by alternately winding or laminating metallic plates in vacuum, and in integrally combining the connecting parts of the metallic plates by diffused junction, the metallic catalyst carrier element being calcines at 1200.degree. C. or above and a pressure of 1 Pa to 10 Pa, preferably l.5 Pa to 10 Pa, to obtain a strong metallic catalyst carrier having oxidization resistance.