As we all know, aluminum is a very active metal. It can react with water to replace the hydrogen in the water and generate strong alumina. Because the surface of the aluminum powder particles exposed to the air has been oxidized by the oxygen in the air, it generates inert alumina for protection. Membrane prevents the contact between aluminum and water. There is a certain amount of alkaline substances in the aerated concrete slurry, such as calcium hydroxide, and alumina can be dissolved in the alkaline solution to generate metaaluminate. When the oxide film on the surface of the aluminum powder is dissolved, the metal aluminum reacts with water to replace the hydrogen in the water and form gelatinous aluminum hydroxide. However, it also hinders the contact between water and the surface of metal aluminum, like aluminum oxide. , So that the reaction can not continue. However, aluminum hydroxide can also be dissolved in alkaline solutions to form metaaluminate. In this way, in the alkaline solution, aluminum can continuously react with water to generate hydrogen gas until the metal aluminum is consumed. The hydrogen is uniformly distributed in the pulp with approximately spherical bubbles, which expands the volume of the slurry and forms a porous silicate product after hardening.
Our aluminium pastes are used in the construction industry for producing autoclaved aerated concrete(AAC). As water based and paste type, it’s convenient to be added into the AAC block making machine, has few pollution on environment.
Pastes with 65%, 70% of solid content are standard. Other solid contents and different Particle size are available to get the right hydrogen gas evaluation, pore structure, density compressive strength, reaction time (dwell time) fit in any production system.