Trimethylaluminium

Chemical properties

The aluminum alkyls are highly flammable and reactive, colorless to yellow liquids at room temperature. The lighter trialkylaluminums ignite spontaneously in air. They are normally supplied and used in a 20% solution with a hydrocarbon solvent, such as hexane, heptane, benzene, toluene. Properties may depend on solvent. Reacts violently with water.

The Uses of Trimethylaluminium

Trimethylaluminium can be used as catalyst for olefin polymerization, pyrophoric fuel, manufacture of straight-chain primary alcohols and olefins, to produce luminous trails in upper atmosphere to track rockets.

The Uses of Trimethylaluminium

Trimethyl aluminum is a highly reactivereducing and alkylating agent. It is used in aZiegler-Natta catalyst for polymerization andhydrogenation.

The Uses of Trimethylaluminium

Trimethylaluminum can be used in the pretreatment of Al2O3/p-type GaSb capacitors.

Definition

A colorless liquid produced by the sodium reduction of dimethyl aluminum chloride. It ignites spontaneously on contact with air and reacts violently with water, acids, halogens, alcohols, and amines. Aluminum alkyls are used in the Ziegler process for the manufacture of high-density polyethene.

Health Hazard

Trimethylaluminum and related alkylaluminum reagents are pyrophoric materials that can react explosively with the moisture in tissues, causing severe burns. The heat of reaction can also ignite the methane gas generated, resulting in thermal burns. Alkylaluminum reagents are corrosive substances, and contact is extremely destructive to the eyes, skin, and mucous membranes. Inhalation of trimethylaluminum and other volatile alkylaluminum compounds may cause severe damage to the respiratory tract and can lead to fatal pulmonary edema.

Health Hazard

As it is pyrophoric and reacts explosivelywith moisture, skin contact can cause a dangerousburn. Contact with eyes can causeblindness. Because of its significant volatility,the risk of inhalation of this compoundis higher than with most other alkyls. Inhalationof its vapors can severely damage therespiratory tract.
TLV-TWA: 2 mg(Al)/m³ (ACGIH).

Flammability and Explosibility

Trimethylaluminum is pyrophoric and burns violently on contact with air or water. Other alkylaluminum reagents show similar behavior, although most are not as volatile as trimethylaluminum. Water or CO2 fire extinguishers must not be used to put out fires involving trialkylaluminum reagents. Instead, dry chemical powders such as bicarbonate, Met-L-X?, or inert smothering agents such as sand or graphite should be used to extinguish fires involving trialkylaluminum compounds.

Potential Exposure

Alkyl aluminum compounds are used as components of olefin polymerization catalysts. They are also used in the synthesis of higher primary alcohols and in pyrophoric fuels, as a catalyst in making ethylene gas; and in plating aluminum.

storage

Safety glasses, impermeable gloves, and a fire-retardant laboratory coat should be worn at all times when working with these compounds. Trialkylaluminum reagents should be handled only under an inert atmosphere.

Shipping

ntial fire or explosion hazard. Shipping: UN3399 Organometallic substance, liquid, water-reactive, flammable, Hazard Class: 4.3; Labels: 4.3 Dangerous Dangerous when wet material, 3-Flammable liquid, technical name Required. UN3051-Spontaneously combustible. Also, this material is dangerous when wet. (Note: this number does not appear in the 49/CFR HazMat tables).

Incompatibilities

The lighter trialkylaluminums ignite spontaneously in air; can self-heat in the air at room temperature without any added energy and may ignite. These compounds are strong reducing agents. Incompatible with oxidizers (chlorates, nitrates, peroxides, permanganates, perchlorates, chlorine, bromine, fluorine, etc.); contact may cause fires or explosions. Keep away from alkaline materials, strong bases, strong acids, oxoacids, epoxides. Incompatible with water, oxygen (air), acids, alcohols, phenols, amines, carbon dioxide; sulfur oxides; halogenated compounds, and many other substances

Waste Disposal

Careful incineration