Sodium tripolyphosphate degelatinizing effect and water reducing principle

What is sodium tripolyphosphate known as a ceramic debonder?

Let's first understand the comparison of these parameters in the process of clay disintegration:

1. Exchange of cations, cation exchange exchange capacity in clay:
Hydrogen ion>aluminum ion>Helium ion>Helium ion>calcium ion>magnesium ion>ammonium ion>potassium ion>sodium ion
Thus, it can be explained that calcium, magnesium ions, and the like which are abundantly present in the clay are more likely to replace sodium or potassium ions, and become precipitates or other chemicals.
2. The ability of clay to adsorb anions is small, and the comparison is: hydroxide ion > carbonate ion > polyphosphate ion > iodide ion > bromide ion > nitrate ion > sulfate ion
3. Space steric effect: Damping and spacing between ions.
4. Chelation effect: through the introduction of the complex, the cations are bonded to form a complex, which reduces the attraction of the ionic bond.
It can be summarized from the above that: sodium tripolyphosphate is surrounded by cation exchange, so that more sodium ions surround the clay, and the displaced calcium and magnesium ions are chelated to form a soluble complex with polyphosphate to supplement the steric hindrance effect. . The clay has a higher fluidity in less water and is evenly dispersed. Therefore, sodium tripolyphosphate is also called ceramic water reducing agent and debonding agent.
Polyphosphates are similar to sodium tripolyphosphate and have the ability to disintegrate. In addition, there are some organic water reducing agents such as sodium oxalate, ammonium oxalate, sodium citrate and the like. Because the operation is not cheap, different manufacturers will formulate their own ceramic debonding agent. The factors involved include: operating temperature, pH, clay properties, cost, etc.

Sodium tripolyphosphate is usually carried out in a neutral environment with high stability and low cost, so it is widely used in ceramic production processes.