Explain some knowledge about emulsified oil in the industry

Knowledge about emulsified oil

Emulsified oil is a tiny oil particle that exists in a stable state (not floating or condensing), with a particle size of about 0.5 to 25m. It is a light brown to dark brown liquid or semi-solid. It is a kind of metal cutting oil. It is mainly used for cooling, lubrication, and is used for metal roughing such as turning, sawing, drilling, and grinding.

Usually, emulsified oil refers to adding nearly 30% to 10% water to 70% to 90% of fuel (gasoline, diesel or heavy oil), adding 0.5% to 1% additives, and emulsifying oil with special equipment. The oil is the water-in-oil type molecular base. The smaller and more uniform the particles, the longer the stabilization period of the emulsified oil.

Emulsified oil and water are mixed in a certain proportion to prepare emulsion, which has anti-rust, cleaning and extreme pressure properties, and is suitable for use as coolant in metal processing, cutting and other processes.

Emulsified oil is composed of base oil and additives (emulsifiers, rust inhibitors). Only when these proportions are properly matched can the emulsified oil be more stable.

base oil

If the base oil, corrosive agent and emulsifier cooperate properly, the emulsified oil can be stabilized. Different oil phases require different HLB value emulsifiers, and the HLB value required by different oil phase combinations also needs to change. The base oil is the carrier of the corrosion inhibitor, and its viscosity affects the stability of the emulsified oil. The viscosity is low and easy to emulsify, but the viscosity is too low, and the protective oil film is too thin, which is not conducive to rust prevention. Therefore, the viscosity of the base oil is moderate.

additive

1. Emulsifier: Emulsifier is a stabilizer of emulsion and a surfactant, which reduces the interfacial tension between mutually incompatible liquids to form an emulsion. The hydrocarbon chain part of) is composed of a polar hydrophilic (hydrophobic) group, and these two parts are located at both ends of the molecule, forming an asymmetric structure.

2. Anti-rust agent: There are mainly two kinds of anti-rust additives: water-soluble anti-rust agent and oil-soluble anti-rust agent. The anti-rust process is mainly the action process of free alkali and water-soluble corrosion inhibitor, such as triethanolamine and metal. An insoluble dense oxide film is formed on the metal surface to prevent electrochemical corrosion of metals.

3. Stabilizer: In addition to stabilizing the oil phase, not layering and being a transparent and uniform phase, the function of the stabilizer can also stabilize the emulsion at room temperature and high temperature, prevent or reduce the stratification of the emulsion and oil separation, and use The stabilizers are mostly isopropanol, polyol (ethylene glycol system), ethanol, high carbon alcohol, diethanolamine, ethanolamine, etc.

4. In addition to the above additives, it also contains extreme pressure additives, alkali retention agents, fungicides, defoamers, complexing agents, etc.

The type of emulsified oil mainly depends on the nature of the emulsifier. Whether the emulsifier or surfactant is soluble in water or oil depends on the relative concentration of hydrophilic and lipophilic groups. Generally, the larger the HLB, the better the hydrophilicity.