Sodium nitrite

        Sodium nitrite, an inorganic compound with the chemical formula NaNO2, is a white crystalline powder, easily soluble in water, slightly soluble in ethanol, methanol, ether, mainly used in the manufacture of azo dyes, but also used as a mordant for textile dyeing, bleaching agent, metal heat treatment agent.

Sodium nitrite as an antifreeze：

         The central role of sodium nitrite as an antifreeze agent is to minimize the effects of freezing on concrete structures at low temperatures to ensure building quality and performance. It can minimize the effects of frost damage and ensure building quality and performance

The specific mechanism of action of sodium nitrite as an antifreeze agent includes the following aspects:

        Antifreeze effect: sodium nitrite can lower the freezing point and prevent concrete from freezing at low temperatures to ensure smooth construction
        Antirust effect: it can control and reduce the corrosion of steel reinforcement, extend the service life of steel reinforcement, and improve the resistance of steel reinforcement to corrosion in corrosive environments
        Coagulation promotion: Sodium nitrite can enhance the early setting effect of concrete and ensure that the setting time of construction meets the national standard.
        Strength improvement: it can improve the degree of hardening and strength of cement, especially in the use of other retarders, to compensate for its weakening effect on the initial strength
        Environmental adaptability: Sodium nitrite can harmonize the performance of different cement characteristics, improve the resistance to corrosion, enhance the strength of cement, accelerate the speed of hardening and improve frost resistance.

When using sodium nitrite as antifreeze, the following points need to be noted:

      Temperature of use: it is usually used at temperatures around zero degrees to ensure the best anti-freezing effect2.
      Cost considerations: although sodium nitrite is more costly, it has superior performance, especially in preventing corrosion of reinforcing steel and improving concrete durability