Aluminum borohydride

Chemical Properties

Volatile, pyrophoric liquid.

Uses

Reducing agent; preparation of borohydrides of heavy metals; fuel for jet engines and rockets.

General Description

A clear, colorless liquid. Slightly denser than water. Contact causes burns to skin, eyes, and mucous membranes. Toxic by ingestion, inhalation and skin absorption. Used to make other chemicals.

Air & Water Reactions

Pyrophoric and explodes in oxygen, but only in the the presence of traces of moisture. Reacts vigorously with water, liberating hydrogen [Merck 11th ed. 1989]. Will flame when in contact with water [Ellern 1968 p. 45].

Reactivity Profile

A powerful reducing agent. Reacts rapidly and dangerously with oxygen and with other oxidizing agents, even weak ones. Incompatible with acids, alcohols, amines, and aldehydes. The borohydride reacts with alkenes and in the presence of oxygen, combustion is initiated even in the absence of moisture. Butene explodes after an induction period, while butadiene explodes immediately. Reaction with dimethylaminoborane or dimethylaminodiborane gives an oily substance which ignites in air and reacts violently with water, [J. Amer. Chem. Soc., 1951, 73, 953].

Hazard

Ignites spontaneously in air, reacts violently with water.

Health Hazard

Fire will produce irritating, corrosive and/or toxic gases. Inhalation of decomposition products may cause severe injury or death. Contact with substance may cause severe burns to skin and eyes. Runoff from fire control may cause pollution.

Fire Hazard

Flammable/combustible material. May ignite on contact with moist air or moisture. May burn rapidly with flare-burning effect. Some react vigorously or explosively on contact with water. Some may decompose explosively when heated or involved in a fire. May re-ignite after fire is extinguished. Runoff may create fire or explosion hazard. Containers may explode when heated.

Safety Profile

A poison. Spontaneously flammable in air. Explodes in oxygen with traces of water. Incompatible with alkenes and water. See also ALUMINUM COMPOUNDS and BORON COMPOUNDS.

Synthesis

S1: polytetrafluoroethylene, EDTA, nickel powder, zirconium powder according to the weight ratio of 1:2:3:2 mixing placed in a tube furnace, the use of argon atmosphere protection, the gas flow rate of 300mL/min, at a rate of 3 C / min rate of the temperature from room temperature to 800 C, keep the reaction 1h, in the argon atmosphere cooled down to room temperature, you can get the powdered mixture; _x000D _ S2: weigh the powdered mixture and aluminum borohydride described in step S1 according to the mass ratio of 1:2, mix the two uniformly and then carry out mechanical ball milling under the condition of high-purity hydrogen to obtain the hydrogen storage material; wherein the ball milling time is 2h, the hydrogen filling protection pressure is 1.0MPa, and the rotational speed is 400r/min. The initial hydrogen release temperature of the hydrogen storage material was tested to be 60 , and 7.2 wt% of hydrogen could be released in 10 s at 180 .

Raw materials

Preparation Products