КРИОЛИТ

Химические свойства

Sodium aluminum fluoride is a snow-white crystalline solid, powder or vitreous mass. The crystalline solid (natural product (cryolite) may be colored reddish or brown or even black but loses this discoloration on heating); synthetic product is an amorphous powder. Odorless

Физические свойства

Habit: massive, granular, pseudocubic euhedral crystals.
Color: snow white, gray, reddish white, or brownish white.
Diaphaneity: transparent to translucent.
Luster: vitreous, greasy.
Streak: white.
Cleavage: [001], [110], [101].
Fracture: uneven.
Occurrence: large bed in a granitic vein in gray gneiss.
Melting point: 1009°C.

Использование

Cryolite is commonly used as an electrolyte for aluminum electrolysis. Alumina is dissolved in molten cryolite is used to dissolve alumina during aluminium processing.

Определение

A natural fluoride of sodium and aluminum or made synthetically from fluorspar, sulfuric acid, hydrated alumina, and sodium carbonate.

Общее описание

An odorless white solid or powder. Mp: 1291°C. Density: 2.95 g cm-3. Dust irritates the eyes and skin; inhaled dust irriates the nose, mouth and lungs. Insoluble in water. Synthesized by fusion of sodium fluoride and aluminum fluoride as a electrolyte in the reduction of alumina to aluminum metal. Occurs in nature as the mineral cryolite. Aqueous suspensions of powdered sodium aluminum fluoride are used as insecticides.

Профиль реактивности

SODIUM ALUMINUM FLUORIDE is non-combustible. Emits toxic fumes when heated to decomposition. Incompatible with strong oxidizing agents and strong acids. Decomposed by bases, which can generate soluble fluorides. Soluble in concentrated sulfuric acid.

Сельскохозяйственное использование

Insecticide: Sodium aluminum fluoride is used as an insecticide on food crops and ornamentals, and also in aluminum refining and making ceramics, glass and polishes. Cryolite is used to control a variety of pests on cucurbits (melons, cantaloupe, water melon, pumpkins, all types of squash), fruiting vegetables (eggplant, pepper, broccoli, Brussels sprouts, cabbage, cauliflower, collards, head and leaf lettuce, kohlrabi), kiwi (in California only), pears, radish, cranberry and peaches, grapefruit, lemon, lime, orange, tangelo, tangerines, tomatoes, apples, potatoes, beans and grapes. Also on ornamental plants, woody shrubs and vines. Not listed for use in EU countries. Registered for use in the U.S

Торговое название

KRYOCIDE®; CHIOLITE®; CRYOLITE 93®; ICE-SPAR®; ICETONE®; KOYOSIDE®; KRIOLIT®; PROKIL® Sodium aluminum fluoride; VILLIAUMITE®

Профиль безопасности

Poison by ingestion. Used as a pesticide. Mutation data reported.When heated to decomposition it emits toxic fumes of Fand NazO. See also FLUORIDES.

Возможный контакт

Sodium aluminum fluoride is used in making pesticides, ceramics, glass, and polishes; in refining reduction of aluminum, flux, glass, and enamel.

Перевозки

UN3077 Environmentally hazardous substances, solid, n.o.s., Hazard class: 9; Labels: 9-Miscellaneous hazardous material, Technical Name Required.

Несовместимости

Incompatible with strong acids such as sulfuric, strong oxidizers, hydrogen fluoride.

Утилизация отходов

In accordance with 40CFR 165 recommendations for the disposal of pesticides and pesticide containers. Must be disposed properly by following package label directions or by contacting your local or federal environmental control agency, or by contacting your regional EPA office.