1-Butyl-3-methylimidazolium hexafluorophosphate[4]
Overview
1-Butyl-3-methylimidazolium hexafluorophosphate (BMIM PF6) is a room-temperature ionic liquid that has gained significant attention in industrial and research applications due to its unique properties. As one of the most studied ionic liquids, it serves as a versatile medium for various chemical processes. Ionic liquids like BMIM PF6 are often called 'designer solvents' because their properties can be tailored by selecting different cation-anion combinations. This particular compound combines the 1-butyl-3-methylimidazolium cation with the hexafluorophosphate anion, resulting in a liquid with excellent thermal stability and negligible vapor pressure.
Physical and Chemical Properties
BMIM PF6 exhibits several remarkable physical properties that make it valuable for specialized applications. With a density of 1.37 g/cm³ and melting point of -8°C, it remains liquid at room temperature, unlike traditional salts. Its thermal stability extends beyond 300°C before decomposition begins. The compound shows good solubility in many polar organic solvents but is immiscible with water, making it useful for biphasic systems. Its ionic conductivity (typically 10-15 mS/cm at 25°C) and wide electrochemical window (~4.5V) are particularly valuable for electrochemical applications. The viscosity is relatively high (∼450 cP at 20°C) compared to conventional solvents.
Main Applications
BMIM PF6 finds extensive use in electrochemistry as an electrolyte for batteries, supercapacitors, and electrodeposition processes. Its non-volatile nature and wide electrochemical window make it safer than traditional organic electrolytes. In green chemistry applications, it serves as a recyclable solvent for catalytic reactions, including hydrogenation and Heck reactions. The pharmaceutical industry utilizes it for extraction processes and as a reaction medium for sensitive compounds. Additional uses include gas separation membranes, lubricants, and as a stationary phase in chromatography.
Safety and Storage
While BMIM PF6 is generally considered safer than many volatile organic solvents, proper handling is essential. The compound may cause skin and eye irritation, requiring appropriate personal protective equipment including gloves and safety goggles. Storage should be in tightly sealed containers under inert atmosphere (argon or nitrogen) to prevent moisture absorption, which can lead to decomposition. Containers should be made of materials resistant to fluorides (e.g., certain plastics or stainless steel). The compound is stable under normal conditions but may decompose at high temperatures, releasing hazardous hydrogen fluoride gas.
B2B Procurement Guide
When procuring BMIM PF6 commercially, buyers should clearly specify purity requirements (typically ranging from 98% to 99.9% for different applications) and any necessary certifications (e.g., battery-grade purity for electrochemical uses). Packaging options vary from small laboratory quantities (50-100g) to bulk industrial drums (25kg or more). For international shipments, proper documentation of non-hazardous materials status should be verified. Lead times can vary significantly based on purity requirements and current market demand, with typical delivery times ranging from 2-8 weeks for custom orders.