1-Hydroxyethyl-3-methylimidazole tetrafluoroborate

1-Hydroxyethyl-3-methylimidazole tetrafluoroborate is an ionic liquid with a polar hydroxyl group and an imidazole cation. It has higher hydrophilicity and polarity than other imidazole ionic liquids. The hydroxyl group can also form stable interactions with other compounds through hydrogen bonding, increasing its solubility as a solvent or solute. [HEMIM][BF₄] has extremely low volatility and vapour pressure, and thus can be used stably at room temperature without volatility, providing better environmental protection and operational safety.

[HEMIM][BF₄] should be stored in airtight containers to avoid absorbing moisture in the air, because it has a certain degree of hygroscopicity, and moisture will affect its physical properties, such as viscosity and conductivity. The storage environment should be a cool, protected place from direct sunlight to prevent possible photodegradation. It can be stored at room temperature (15-25°C) without special refrigeration. Due to its chemical stability, contact with strong acids, bases or oxidising agents should be avoided to prevent unwanted chemical reactions or corrosion of the container. Its low volatility means that there is a low risk of airborne contamination even when used at room temperature, but it is still advisable to operate in a well-ventilated environment and avoid prolonged exposure to confined spaces. Although tetrafluoroborate is relatively inert and does not corrode common materials such as metal or glass, contact with other chemicals at elevated temperatures may produce corrosive by-products. For humans, although ionic liquids generally have low toxicity, direct contact with skin or eyes may cause mild irritation, so protective gloves and goggles should be worn during handling to ensure safe handling.