Introduction
A solvent is a substance that dissolves a solute, resulting in a solution. A solvent is usually a liquid but can also be a solid, a gas, or a supercritical fluid. The quantity of solute that can dissolve in a specific volume of solvent varies with temperature.
Major uses of solvents are in paints, paint removers, inks, dry cleaning.
Specific uses for organic solvents are in dry cleaning (e.g. tetrachloroethylene); as paint thinners (toluene, turpentine); as nail polish removers and solvents of glue (acetone, methyl acetate, ethyl acetate); in spot removers (hexane, petrol ether); in detergents (citrus terpenes); and in perfumes (ethanol).
Solvents find various applications in chemical, pharmaceutical, oil, and gas industries, including in chemical syntheses and purification processes.
Purification is an operation that separates the solid matter like impurities and particles from chemical solution by a porous membrane. It is a common preprocessing task to get clarified solvent before analysis by precision instrument, such as HPLC, LC-MS, GC-MS, ICP-MS, etc.
Methods OF PURIFICATION OF REAGENTS AND SOLVENTS
Many methods exist for the purification of reagents and solvents.
A number of these methods are routinely used in synthetic as well as analytical chemistry and biochemistry.
It is important to note that more than one method of purification may need to be implemented in order to obtain compounds of highest purity.
Common methods of purification are:
- Solvent Extraction and Distribution
- Distillation
- Recrystallisation
- Sublimation
- Electrophoresis
- Chromatography
Extraction of a substance from suspension or solution into another solvent can sometimes be used as a purification process.
Thus, organic substances can often be separated from inorganic impurities by shaking an aqueous solution or suspension with suitable immiscible solvents such as benzene, carbon tetrachloride, chloroform, diethyl ether, diisopropyl ether or petroleum ether.
After several such extractions, the combined organic phase is dried and the solvent is evaporated.
Grease from the glass taps of conventional separating funnels is invariably soluble in the solvents used.
Contamination with grease can be very troublesome particularly when the amounts of material to be extracted are very small.
Instead, the glass taps should be lubricated with the extraction solvent; or better, the taps of the extraction funnels should be made of the more expensive material Teflon.
Extraction of a substance from suspension or solution into another solvent can sometimes be used as a purification process.
Thus, organic substances can often be separated from inorganic impurities by shaking an aqueous solution or suspension with suitable immiscible solvents such as benzene, carbon tetrachloride, chloroform, diethyl ether, diisopropyl ether or petroleum ether.
After several such extractions, the combined organic phase is dried and the solvent is evaporated.
Grease from the glass taps of conventional separating funnels is invariably soluble in the solvents used.
Contamination with grease can be very troublesome particularly when the amounts of material to be extracted are very small.
Instead, the glass taps should be lubricated with the extraction solvent; or better, the taps of the extraction funnels should be made of the more expensive material Teflon.
Recommend Device
Solvent and chemical purification should be done with chemical resistant vacuum pump to accelerate the filtration process with the aid of vacuum and reduce the pump corrosion by chemical vapors. However, Max. Vacuum has limited impact on filtration speed; for example, Max. Vacuum of Rocker 300C is 145 mbar which stands that it has utilized 85% of atmospheric pressure as driving force, so deeper vacuum has only little effect on increasing filtration efficiency. Nevertheless, a deeper vacuum of pump is highly recommended while viscous fluid needs to be filtrated.
In addition, flow rate shows better effect on filtration than Max. Vacuum. Generally, larger volume of container, higher flow rate of pump should be chosen.
The Rocker solvent purification system is equipped with a chemical resistant vacuum pump. It uses the principle of diaphragm action, does not need to use oil for lubrication and maintenance, and has no oil mist pollution. Which is suitable for solvent purification, HPLC mobile phase purification, laboratory vacuum filtration, etc.
Applications
- Purification of HPLC mobile phase, such as ACN, Methanol and THF
- Solvent purification for Ion Chromatography (IC)
- Chemical solution filtration and purification
