Low Melting Point
Ever tried melting table salt? You can’t melt it in a kitchen because they have a melting point of 801○C! Table salt can easily be dissolved in water, but cannot be melted. This is due to the presence of cations and anions in salt. They pack well to each other, lose their mobility and crystallize. However, in ionic liquids, cations and anions are poorly coordinated. They do not pack, keep moving around, making the solvent liquid.
They do not Evaporate
Typical solvents, such as water boil and evaporate, but ionic liquids remain liquid even when boiled at more than 400○C. This occurs because ionic liquids comprise of charged cations and anions, which are held together by strong coulombic interactions. Breaking this bond is difficult, thus evaporation does not take place. On the other hand, typical solvents comprise of neutral molecules which are held together by weak forces such as hydrogen bond. These bonds are broken easily which makes molecules evaporate.
Advantages of Ionic Liquids
Environmental pollution due to energy industries has been on the rise since the past many years. Companies involved in the process and scientists are expected to reduce hazardous emission by discovering sustainable solutions. One such method that has emerged in the past few years is the use of ionic liquids. Find out here, why they have been proposed as energy efficient solvents in the industry and labeled as environmental friendly:
Reduces Use of Water in Textile Industry
The textile industry is known as the biggest water consumers amongst all industries. Approximately 200 liters of water is required to process 1 kilogram of textile material. Ionic liquids possess the potential to be used in place of water in the textile industry. The operating efficiencies of many textile companies can increase with the use of ionic liquids.
Textile dyes are organic compounds i.e. they are carbon based. During the dyeing process, dyes are dissolved in a solvent, which is usually water. Through the process known as diffusion, this water is passed into the interior of the material. Due to contamination, the wastewater generated in the textile dyeing process is difficult to treat.
Due to their unique properties, ionic liquids are considered as an efficient replacement of water. In addition to low melting properties, ionic liquids comprise of positively charged ions, cations and negatively charged ions, anions. With custom synthesis and the ability to dissolve different chemicals and materials, ionic liquids can replace various conventional solvents in the dyeing process.
Ionic liquids possess great stability over a wide range of temperatures and are neither volatile nor flammable. These are great benefits, which is why they are preferred in a production environment. This is why they are considered environmental friendly elements and safe for human health. Additionally, they have negligible vapor pressure and do not volatilize, which makes them recoverable for reuse. Volatile organic compounds are not emitted making it a safe and environmental friendly element.
As a renewable material, cellulose possesses great importance. It is used to manufacture numerous fibers. 40 billion ton is renewed each year; however, only 2 million is used for further processing. Lack of suitable solvents is the main obstacle for the chemical dissolution process. Ionic liquids have simplified this process. They can be recycled entirely and the cellulose concentration in the viscose method ranges from 8 to 12% weight.
Ionic Liquids: How are They Different
Ionic liquids are salts with a very low melting point i.e. 100○C and comprise of cations and anions. They have emerged as an environmental friendly alternative because they are non-volatile solvents. Attracting significant attention from different chemical companies, ionic liquids are known as new novel chemical agents. They are quite different as compared to other chemical elements due to these unique properties:
Dissolve different Materials and Chemicals
Cations and anions can be modified according to different chemical structures and impart various properties to the ionic liquids. Ionic liquids can be used to dissolve cellulose, a biopolymer in wood and plants. Other biopolymers such as lignin and chitin can be dissolved using ionic liquids. With the help of chemical modification and casting new polymers from the solution, new bio-derived materials can be formed. Additionally, waste of wood and paper can also be modified and useful materials can be formed.
Can Conduct Electricity
Pure water does not conduct electricity due to lack of ions. With positive and negative ions both, ionic liquids carry charge and can be classified as electrolytes – liquids that conduct electricity. With the help of electrochemical means, ionic liquids can be used in dissolving and recovering precious metals from electronic waste.
Applications of Ionic Liquids
Emerged as possible alternatives to volatile organic solvents, ionic liquids have numerous applications in a number of research areas. With their unique properties and characteristics, ionic liquids are known as green and environment friendly solvents. High thermal and electrochemical stability, negligible vapor pressure, high solvating power, are only few of the benefits of ionic liquids. With applications in numerous fields, ionic liquids are most popularly used in:
The use of ionic liquids in electrochemical devices has proved to be positive with outstanding results. When ionic liquids were used with devices such as lithium ion batteries, super capacitors, dye-sensitized solar cells and polymer-electrolyte fuel cells, positive results were witnessed. Acting as an electrolyte in all electrochemical devices, ionic liquids should be resistant to electrochemical oxidation and radiation. The two major benefits why these are utilized with electrochemical devices are the non-volatility and prevention of electrolytes from drying during the operation. Offering a wide electrochemical window is the main requirement of an ionic liquid to be used in developing electrochemical applications. Additionally, the high viscous liquid, when mixed with propylene carbonate, results in a decrease in viscosity, providing better output data as compared to traditional systems.
Ionic liquids serve as promising solvents in various organic reactions such as Bails-Hillman, esterification, Diels-Alder, Heck Reaction, isomerization reactions and many more. The progress of the reaction is determined by concentrations, pressure and temperature of the reactants. Furthermore, it has also been observed that, viscosity plays an essential role in reaction kinetics. According to the results, in addition to viscosity, the rates are influenced by a solvent property – its variation, independence of viscosity and changing of one series of anions to another.
Solvent extraction is utilized in nuclear processing, production of organic compounds, ore processing, processing perfumes and other different industries. Ionic liquids are used to separate toxic metal ions and organic molecules. Currently, ionic liquids are used to separate metal ions with the use of crown ethers. Crown ethers help in extracting metal ions from aqueous solutions. The efficiency of this process depends on the counter anions as well as cations. To remove strontium nitrate from aqueous phase, ionic liquids are used; since crown ethers are inefficient in this process.
Available Products For Sale Ionic Liquids