Understand the composition of antifreeze (Dieselpartsworld) 2016-01-22    

Understand the composition of antifreeze
Antifreeze solution is generally composed of basic liquid and additives, the base fluid is composed of water and glycol or two glycol glycol.
Additives include anti rust agent, anti mildew agent, pH regulator (Huan Chongji), antifoaming agent and colorant etc..
Base fluid
The base fluid of antifreeze is composed of water and alcohol. Choose alcohol principle is requirements of wide source and low price, specific heat and thermal conductivity should be close to. At present, the most commonly used is ethylene glycol and two glycol. Table 1 is the freezing point of ethylene glycol and water in different proportions, table 2 is two DEG and water mixture after freezing. According to the use of different areas, the alcohol content of the antifreeze in general from 40% to 60%.
Additives
Antirust
Can effectively prevent the mixture of ethylene glycol and water mixture to prevent corrosion of engine cooling system. Commonly used anti rust agent are generally soluble in water. For example: borate, aluminate, chromate, nitrite, benzoic acid salt and benzo nitrogen Zun.
(9h regulator) buffer in the use process, the antifreeze solution pH value should be as far as possible to maintain in the July 11, so as to ensure produced by the oxidation of alcohols, acids and fuel oil penetration over the formation of acid on metal corrosion, and ensure the antifreeze is not affected by fungal invasion and rotten metamorphic. The PH regulator is the most commonly used organic amine.
Anti foam agent
The foam formed by the waste gas and the mixed air is not favorable for heat transfer, therefore, the anti freezing liquid does not wish to have foam generation in use. Commonly used anti foam agent has high alcohol, organic silicon polymer and some surface active agent.
In addition, a fungicide, dyes often add antifreeze, sometimes adding trapping agent.