Refractory phosphate cement preferred dihydrogen aluminum phosphate

A substance in which a refractory material composed of a refractory coarse particle material and a powder material is cemented together is also referred to as a "cementing agent". Used as a refractory binder, it not only requires good cold and hot bonding strength, but also requires good construction and molding properties.
Classification of refractory materials, especially for indeterminate refractory materials, is classified according to the properties and uses of the bonding materials, and is generally classified according to the chemical nature of the bonding agent and the combined hardening conditions.
The inorganic binder and the organic binder are classified according to the chemical nature of the binder.
1. Inorganic binder.
According to the nature of their compounds, they can be divided into 6 categories.
The first type is silicates. Including calcium silicate cement, water glass (including sodium silicate, potassium silicate water glass) and combined clay.
The second category is aluminate, including ordinary calcium aluminate cement (also known as alumina cement or high alumina cement), pure calcium aluminate cement aluminate cement, and spinel aluminate cement.
The third category is phosphates. Including phosphoric acid, aluminum dihydrogen phosphate, magnesium phosphate, ammonium phosphate, aluminum chromium phosphate, sodium tripolyphosphate, sodium hexametaphosphate, etc.
The fourth category is sulfates. Including magnesium sulfate, aluminum sulfate, iron sulfate, and the like.
The fifth category is chlorides. Including magnesium chloride [brine], ferric chloride, polyaluminum chloride (also known as basic aluminum chloride).
The sixth category is a sol. Including silica sol, aluminum sol, silica alumina sol, and the like.

2. Organic binder.
According to the method of preparation, it is divided into two categories.
The first category is natural organic matter. That is, isolated from natural organic matter, including starch, paste crystal, gum arabic, sodium alginate, pulp waste liquid, tar and asphalt.
The second type is synthetic organic matter, that is, synthesized by a chemical reaction or a polycondensation reaction, and includes a binder which is hydraulically, air-hard, and thermosetting according to the hardening conditions of the binder.
1. Hydraulic binder. Adding to the bulk refractory aggregate, adding water and mixing and forming, after curing under humid conditions, normal coagulation and hardening bonding agents, such as Portland cement and aluminate cement, can occur.
2. A gas-hard binder. After being mixed with the bulk refractory aggregate, the binder can be coagulated and hardened under the condition of self-heating drying [normal temperature]. Such a binder is generally added with a hardener such as water glass and sodium fluorosilicate. Phosphoric acid or aluminum dihydrogen phosphate plus calcium aluminate cement or magnesium oxide, silica fine powder plus calcium aluminate cement or magnesium oxide.
3, the thermosetting bond, after mixing with the bulk refractory aggregate, can harden the bond when heated and baked, such as phosphoric acid, aluminum dihydrogen phosphate, resol phenolic resin.