1-Propyl-3-Methylimidazolium Hydrogensulfate stands out as an ionic liquid that has found a niche in labs and industry for a reason. The compound carries a formula of C7H15N2O4S and a molecular weight of about 223.27 g/mol. Structured with a propyl chain and a methyl group attached to the imidazolium ring, this compound forms a salt with the hydrogensulfate anion. You often see it classified under HS Code 2933, thanks to its imidazole ring at the core of the structure. More than a sum of atoms, the presence of both hydrophilic and hydrophobic zones in a single molecule sets it apart within the world of advanced solvents and catalyst supports.
This ionic liquid offers a range of physical forms. You might encounter it as a viscous liquid, a gel, or even in crystalline, powdered, or pelletized states. The color typically settles close to pale yellow or colorless. Its density ranges between 1.20 to 1.25 g/cm3 depending on environmental conditions and purity. Liquid versions pour thick, almost honey-like, which reflects the strong ionic cohesion making it stable yet easy enough to work with in laboratory glassware. It dissolves well in water and polar organic solvents, allowing flexible application as a neat liquid, aqueous solution, or crystallized solid. Unlike some salts, 1-Propyl-3-Methylimidazolium Hydrogensulfate resists decomposition up to 200°C. My own work in synthesis once called for a solvent capable of withstanding both high acidity and temperature swings, and this ionic liquid held up under pressure while retaining full reactivity.
You’ll often find it supplied in lab-grade or industrial volumes as a raw material, sold by the gram, kilogram, or by liter as a prepared solution. Bulk suppliers offer carefully sifted flakes, compacted pearls, and crystalline powders, as these different forms play into varying dissolution rates and storage considerations. As a raw material, the quality specifications require a purity upwards of 97% to satisfy chemists in fine chemical synthesis, metal catalysis, or electrochemistry. Experienced practitioners look for consistent particle size and low moisture content, especially when handling batch processes. Liquid samples arrive in sturdy, chemical-resistant bottles with full certificate of analysis and safety data sheets.
The hydrogensulfate group imparts acidity, enhancing reactivity in acid-catalyzed transformations. This means 1-Propyl-3-Methylimidazolium Hydrogensulfate can swap with strong mineral acids in many reactions. In the lab, I once used it as both a catalyst and solvent, observing how its ionic composition actually sped up reaction rates that otherwise dragged in non-ionic solvents. Thermal stability makes it compatible with high-temperature procedures. The imidazolium cation increases polarity, which draws in polar substrates and gives it a leg up in separation and purification, especially for those difficult-to-isolate organic and inorganic compounds.
Despite its usefulness, you have to take safety seriously with 1-Propyl-3-Methylimidazolium Hydrogensulfate. Its chemical properties place it between benign and potentially hazardous. Prolonged contact with skin or eyes risks mild to moderate irritation, and inhalation of fine powders or vapors causes respiratory discomfort in poorly ventilated spaces. It doesn’t fall into the most hazardous classes, but it cannot be considered fully safe without proper personal protective equipment—nitrile gloves, goggles, and lab coat become must-haves. Disposal depends on local chemical waste protocols, since residues can acidify wastewaters. Responsible users run regular risk assessments and integrate safety data into every lab or plant procedure. As industries focus on greener solutions, there’s an open conversation about finding less persistent, more biodegradable alternatives or reclaiming ionic liquids with novel filtration and distillation systems to reduce long-term harm.
Manufacturers deploy 1-Propyl-3-Methylimidazolium Hydrogensulfate in catalysis, as a soft acid catalyst in complex organic transformations, and as a recyclable medium in separation columns. The push for efficient, recoverable solvents has lifted demand in green chemistry—for instance, in extraction of rare earth metals, biomass conversion, and pharmaceutical intermediate synthesis. In my own hands-on experience, selectivity and yield improved in multi-step preparations, and the solvent’s tunable polarity helped refine complicated product purifications. Process engineers appreciate the flexibility, as it can be regenerated through distillation, which sidesteps traditional waste.
The chemical industry faces a dual challenge: harnessing the performance of ionic liquids like 1-Propyl-3-Methylimidazolium Hydrogensulfate while minimizing environmental impact. Better engineering controls in manufacturing plants can prevent atmospheric release. Companies need robust recycling protocols to recover and reuse spent solution, and research now explores ways to degrade or transform spent ionic liquids into harmless byproducts. Training for safe handling, strict compliance with chemical hygiene, and scaling up biodegradable alternatives should move in step with broader adoption.
| Specification | Details |
|---|---|
| Molecular Formula | C7H15N2O4S |
| Molecular Weight | 223.27 g/mol |
| Density | 1.20–1.25 g/cm³ |
| Physical Form | Liquid, powder, flakes, pearls, crystal |
| Solubility | Water and polar organics |
| Thermal Stability | Up to 200°C |
| HS Code | 2933 (imidazole derivatives) |
| Hazard Status | Mildly hazardous, irritant |
| Applications | Catalyst, raw material, solvent, separation |
