Hitachi, Ltd.

Japan Atomic Energy Research Institute

Doryokuro Kakunenryo Kaihatsu Jigyodan

Johoku Chemical Co., Ltd.

Kenji Motojima

Fumio Kawamura

Koichi Chino

Kiyomi Funabashi

Susumu Horiuchi

Kunio Kamiya

Misato Horie

Yoshihide Komaki

Kazuya Suzuki

Katsuaki Ichiyanagi

Hideo Kamiyama

Shin-ichiro Torada

Enzo Tachikawa

Matae Iwasaki

A method of recovering palladium from a palladium-containing aqueous solution by electrolysis is provided. The method comprises the steps of dc-electrolyzing the palladium-containing aqueous solution acidified with nitric acid by using an electrolytic cell equipped with a platinum electrode as a cathode to thereby deposit and collect palladium on the cathode, taking the cathode on which palladium has been deposited and collected out of the electrolytic cell, transferring the palladium-deposited cathode to a recovery vessel containing dilute nitric acid therein, and mechanically shaking the cathode in the recovery vessel to remove and recover palladium from the cathode. An apparatus for carrying out the above-described method is also provided.

Method of recovering palladium by electrolysis and apparatus therefor

A metal ion adsorbent free from release of oxine from activated charcoal even at a high temperature of more than 150.degree. C. is prepared by adsorbing oxine or its derivative onto activated charcoal, adsorbing a phenol onto activated charcoal, dipping the resulting activated carbon into an aqueous solution of aldehyde such as formaldehyde, methylolizing oxine or its derivative in the presence of an acid or an alkali as a reaction promoter, and binding the methylolized oxine derivative, and the phenol by copolymerization or oxine can be methylolized in advance and then adsorbed onto the activated charcoal in place of adsorption of oxine onto the activated carbon, followed by methylolization of the oxine on the surface of the activated charcoal.

Oxine impregnated activated charcoal metal ion adsorbent

Zeolite is contacted with an aqueous solution containing at least one of copper, nickel, cobalt, manganese and zinc salts, preferably copper and nickel salts, particularly preferably copper salt, in such a form as sulfate, nitrate, or chloride, thereby adsorbing the metal on the zeolite in its pores by ion exchange, then the zeolite is treated with a water-soluble ferrocyanide compound, for example, potassium ferrocyanide, thereby forming metal ferrocyanide on the zeolite in its pores. Then, the zeolite is subjected to ageing treatment, thereby producing a zeolite adsorbent impregnated with metal ferrocyanide in the pores of zeolite. The adsorbent can selectively recover cesium with a high percent cesium removal from a radioactive liquid waste containing at least radioactive cesium, for example, a radioactive liquid waste containing cesium and such coexisting ions as sodium, magnesium, calcium and carbonate ions at the same time at a high concentration. The zeolite adsorbent has a stable adsorbability for a prolonged time.

Process for producing zeolite adsorbent and process for treating

A detergent-containing radioactive liquid waste originating from atomic power plants is concentrated to have about 10 wt. % detergent concentration, then dried in a thin film evaporator, and converted into powder. Powdered activated carbon is added to the radioactive waste in advance to prevent the liquid waste from foaming in the evaporator by the action of surface active agents contained in the detergent. The activated carbon is added in accordance with the COD concentration of the radioactive liquid waste to be treated, and usually at a concentration 2-4 times as large as the COD concentration of the liquid waste to be treated. A powdery product having a moisture content of not more than 15 wt. % is obtained from the evaporator, and pelletized and then packed into drums to be stored for a predetermined period.

Process for treatment of detergent-containing radioactive liquid wastes

A process is, herein, disclosed for preparing oxine impregnated-activated charcoal comprising contacting solid oxine with activated charcoal.

Process for preparing oxine impregnated-activated charcoal

A novel process and an apparatus are herein disclosed for separating molybdenum-99 from irradiated uranium.

Volitilization process for separation of molybdenum-99 from irradiated

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Mito, Japan

Kenji Motojima