Beryllium fluoride Property

Melting point:

545 °C

Boiling point:

1169°C (estimate)

Density 

1,986 g/cm³

solubility 

very soluble in H2O; slightly soluble in ethanol

form 

Powder

color 

White

Water Solubility 

very soluble H2O [MER06]; slightly soluble alcohol [HAW93]

EPA Substance Registry System

Beryllium difluoride (7787-49-7)

Safety

Hazard Codes 

N-T+,Xi

Risk Statements 

51/53-49-48/23-43-36/37/38-26-25

Safety Statements 

61-53-45

RIDADR 

UN1566

Hazard Note 

Irritant

HazardClass 

6.1

PackingGroup 

II

Hazardous Substances Data

7787-49-7(Hazardous Substances Data)

Toxicity

LD50 orl-rat: 98 mg/kg XEURAQ UR-154,1951

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Danger

Hazard statements

H301Toxic if swalloed

H311Toxic in contact with skin

H314Causes severe skin burns and eye damage

H330Fatal if inhaled

H350May cause cancer

H372Causes damage to organs through prolonged or repeated exposure

H411Toxic to aquatic life with long lasting effects

Precautionary statements

P260Do not breathe dust/fume/gas/mist/vapours/spray.

P264Wash hands thoroughly after handling.

P264Wash skin thouroughly after handling.

P270Do not eat, drink or smoke when using this product.

P271Use only outdoors or in a well-ventilated area.

P280Wear protective gloves/protective clothing/eye protection/face protection.

P284Wear respiratory protection.

P301+P310IF SWALLOWED: Immediately call a POISON CENTER or doctor/physician.

P301+P330+P331IF SWALLOWED: Rinse mouth. Do NOT induce vomiting.

P302+P352IF ON SKIN: wash with plenty of soap and water.

P303+P361+P353IF ON SKIN (or hair): Remove/Take off Immediately all contaminated clothing. Rinse SKIN with water/shower.

P304+P340IF INHALED: Remove victim to fresh air and Keep at rest in a position comfortable for breathing.

P305+P351+P338IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.

P310Immediately call a POISON CENTER or doctor/physician.

P312Call a POISON CENTER or doctor/physician if you feel unwell.

P314Get medical advice/attention if you feel unwell.

P320Specific treatment is urgent (see … on this label).

P321Specific treatment (see … on this label).

P322Specific measures (see …on this label).

P330Rinse mouth.

P361Remove/Take off immediately all contaminated clothing.

P363Wash contaminated clothing before reuse.

P403+P233Store in a well-ventilated place. Keep container tightly closed.

P405Store locked up.

P501Dispose of contents/container to..…

Beryllium fluoride Chemical Properties,Usage,Production

Description

Beryllium fluoride has the formula, BeF2, and is a hygroscopic, amorphous solid with a melting point of 800°C. It is soluble in water and is used in beryllium metallurgy in which the metal, Be, is employed as an alloy. Solid crystalline BeF2 has a silica-like structure with beryllium in a four-coordinate position.

Chemical Properties

Beryllium fluoride is readily soluble in water, dissolving in its own water of hydration as BeF2·2H2O. The compound cannot be crystallized from solution and is prepared by thermal decomposition of ammonium fluoberyllate, (NH4)2BeF4.

Physical properties

Glassy solid; tetragonal crystal system; hygroscopic; density 2.1 g/cm³; melts BERYLLIUM FLUORIDE 101 at 552°C; vaporizes at 1,169°C; very soluble in water; sparingly soluble in alcohol.

Uses

manufacture of Be and Be alloys; manufacture of glass; in nuclear reactors.

Uses

Beryllium fluoride is used in biochemistry, particularly protein crystallography, since it binds in some of the same ways as phosphate does in human tissues. ADP and beryllium fluoride together tend to bind to ATP sites and inhibit protein action, making it possible to crystallize proteins in the bound state. Beryllium fluoride forms a basic constituent of the preferred fluoride salt mixture used in liquid-fluoride nuclear reactors. Typically, beryllium fluoride is mixed with LiF to form a base solvent, into which fluorides of uranium and thorium are introduced. Beryllium fluoride is exceptionally chemically stable and LiF/BeF2 mixtures have low melting points and the best neutronic properties of any of the fluoride salt combinations appropriate for reactor use.

Uses

Beryllium fluoride (BeF2) is an example of beryllium that has an oxidation state of +2, combining with a negative anion element with an oxidation state of –1. Beryllium fluoride is also used along with magnesium metal in the chemical reduction process to produce beryllium metal.

Definition

ChEBI: The fluoride salt of beryllium (+2 oxidation state). In the solid state it exists as a glass, with four-coordinate Be2+ tetrahedral centres and two-coordinate fluoride centres. As a gas it adopts a linear triatomic structure and in the liquid state a fluctuating tetrahedral structure. In protein crystallography it is used as a mimic of phosphate.

Preparation

Beryllium fluoride is made by thermal decomposition of ammonium beryllium fluoride at 900 to 950°C.

Manufacturing Process

First, beryllium hydroxide is dissolved in an ammonium hydrogen fluoride solution. The resulting ammonium tetrafluoroberyllate is dissociated to a small extent in the solution that the pH can be varied over a wide range without precipitating beryllium hydroxide. Impurities can thus be precipitated relatively easily as hydroxides. Aluminum is precipitated as hydroxide by increasing the pH to 8.3. Chromium and manganese are precipitated by oxidation with lead dioxide, and manganese is precipitated by oxidation with lead dioxide and manganese dioxide. Copper, nickel, and lead are precipitated as sulfides. Ammonium tetrafluoroberyllate is freely soluble in water. When concentrated by evaporation, it crystallizes without water or hydration. Above 130 ?C, it dissociates into ammonium fluoride and beryllium fluoride. Between 900 and 1100 ?C, ammonium tetrafluoroberyllate dissociates into gaseous beryllium fluoride and gaseous ammonium fluoride. The latter can be recycled into the process as ammonium hydrogen fluoride by dissolving it in aqueous hydrogen fluoride. Cooling produces beryllium fluoride as vitreous grains.

General Description

Odorless white solid. Denser than water.

Air & Water Reactions

Water soluble.

Reactivity Profile

Beryllium fluoride is incompatible with the following: Acids, caustics, chlorinated hydrocarbons, oxidizers, magnesium, molten lithium .

Hazard

A known carcinogen. Toxic by inhalation and ingestion.

Health Hazard

Any dramatic weight loss should be considered as possible first indication of beryllium disease. Inhalation causes irritation of nose, throat, and lungs, severe pneumonitis, and/or pulmonary edema. Ingestion causes fatigue, weakness, loss of appetite. Contact with eyes causes severe irritation and burns. Contact with skin causes dermatitis and non-healing ulcers.

Fire Hazard

Special Hazards of Combustion Products: Toxic and irritating vapor of unburned material may form in fire.

Safety Profile

Confirmed carcinogen withexperimental carcinogenic and tumorigenic data byinhalation. Poison by ingestion, subcutaneous,intravenous, and intraperitoneal routes. Incompatible with Mg. When heated to decomposition, itemits very toxic fumes of BeO and F