Ammonium metavanadate

Chemical properties

Ammonium metavanadate is an inorganic acidic salt with the formula NH4VO3. It is a white or slightly yellow crystalline powder. Slightly soluble in cold water, hot ethanol and ether, soluble in hot water and dilute ammonium hydroxide. It is an important intermediate in the purification of vanadium.

The Uses of Ammonium metavanadate

Ammonium vanadium oxide is used as a catalyst in organic synthesis, and as an analytical reagent in laboratories. It is employed in the preparation of vanadate. It acts as a sensor for the determination of N-acetyltransferase activity in humans. Further it finds use in dyes, varnishes, indelible inks, drier for paints, and in photography. With copper carbonate, it has been shown to enhance the catalytic activities. Ammonium metavanadate is an environmental-friendly catalyst to prepare alpha-hydroxyphosphonate derivatives in high yield through the reaction of aryl/heteroaryl aldehydes with triethylphosphonate derivatives.

The Uses of Ammonium metavanadate

In dyeing and printing on woolens; staining wood black; manufacture of vanadium black and "indelible ink"; producing vanadium luster on pottery; as photographic developer; in hematoxylin staining in microscopy; as reagent in analytical chemistry.

What are the applications of Application

Ammonium metavanadate is a commonly employed vanadate preparation

What are the applications of Application

Ammonium metavanadate is a water soluble inorganic acid. It is a cheaply available, mild and efficient catalyst. Its ability to alter female reproduction has been studied in swiss albino mice.
Ammonium metavanadate may be used as a substrate in the synthesis of the following:
silver vanadate (AgVO3) nanorods
manganese vanadate nanobelts
vanadium oxide hydrate semi-microspheres
It may be used as a catalyst in the synthesis of the following:
azalactone derivatives
2,4,5-triaryl-1H-imidazoles
octahydroquinazolinone derivatives
α-hydroxyphosphonates

Preparation

Ammonium metavanadate, NH4VO3, plays an important role in the preparation of vanadium oxides and other ammonium compounds, such as NH4V3O8, (NH4)2V3O8, and NH4V4O10, which were found to possess interesting electrochemical properties.
Synthesis of ammonium metavanadate: Vanadium iron powder and charcoal powder mixed with a certain proportion of granulation for roasting, and the role of liquid alkali to generate sodium vanadate, the clear liquid after concentration, filtration, neutralization with hydrochloric acid to Ph7.5 ~ 8, filtration, filtrate heating to 70 ~ 80 ℃, stirring under the addition of ammonium chloride solution, the precipitate by centrifugal separation, washing, drying, the production of ammonium metavanadate crystals.
tailoring the size and shape-new path for ammonium metavanadate synthesis

General Description

Ammonium metavanadate appears as a white crystalline powder. Slightly soluble in water and denser than water. Decomposes at 410°F. May release toxic fumes. Moderately toxic. An irritant. Used as a dryer for paints and inks, and for dyes. Loses ammonia upon heating.

Air & Water Reactions

Slightly soluble in water.

Reactivity Profile

Acidic inorganic salts, such as Ammonium metavanadate, are generally soluble in water. The resulting solutions contain moderate concentrations of hydrogen ions and have pH's of less than 7.0. They react as acids to neutralize bases. These neutralizations generate heat, but less or far less than is generated by neutralization of inorganic acids, inorganic oxoacids, and carboxylic acid. They usually do not react as either oxidizing agents or reducing agents but such behavior is not impossible. Many of these compounds catalyze organic reactions.

Health Hazard

TOXIC; inhalation, ingestion or skin contact with material may cause severe injury or death. Contact with molten substance may cause severe burns to skin and eyes. Avoid any skin contact. Effects of contact or inhalation may be delayed. Fire may produce irritating, corrosive and/or toxic gases. Runoff from fire control or dilution water may be corrosive and/or toxic and cause pollution.

Fire Hazard

Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes. Some are oxidizers and may ignite combustibles (wood, paper, oil, clothing, etc.). Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated.

Flammability and Explosibility

Non flammable

Safety Profile

Poison by ingestion, subcutaneous, intravenous, intratracheal, and intraperitoneal routes. Moderately toxic by skin contact. An experimental teratogen. Other experimental reproductive effects. Mutation data reported. See also VANADIUM COMPOUNDS. When heated to decomposition it emits toxic fumes of NH3, VOx, and NOx.

Potential Exposure

It is used in the metals industry to make alloys, chemical reactions, dyes, inks, varnishes, printing, medicines, and photography.

Shipping

UN2859 Ammonium metavanadate, Hazard Class: 6.1; Labels: 6.1-Poisonous materials.

Purification Methods

Wash the salt with H2O until free from Cl-ions and dry it in air. It is soluble in H2O (5.18g/100mL at 15o, 10.4g/100mL at 32o) but is more soluble in dilute NH3. It crystallises from conductivity water (20mL/g). When heated at relatively low temperature, it loses H2O and NH3 to give vanadium oxide (V2O5), and at 210o it forms lower oxides. [Baker et al. Inorg Synth III 117 1950.] Its solubility in H2O is 0.52% (15o), 1% (32o) and 1.6% (50o). After washing the technical grade salt with H2O, it had Na, Mn and U at 0.06, 0.2 and 0.1 ppm, respectively. [Brauer in Handbook of Preparative Inorganic Chem (Ed. Brauer) Academic Press Vol II p 1272-1273 1965.]

Incompatibilities

Moisture forms an acidic solution. React with bases and alkaline material: may generate heat and release flammable hydrogen gas.