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Multiphasic Liquid
A multiphasic liquid is a mixture consisting of more than two immiscible liquid phases. Biphasic mixtures consisting of two immiscible phases are very common and usually consist of an organic solvent and an aqueous phase ("oil and water"). Multiphasic liquids can be used for selective liquid-liquid extractions or for decorative purposes, e.g. in cosmetics. While it is possible to get multilayered phases by layering nonpolar and aqueous phases of decreasing densities on top of each other, these phases will not separate after mixing like true multiphasic liquids. Compositions The following types of multiphasic liquids exist: Triphasic systems * Nonpolar solvent / aqueous biphasic mixture *: ''e.g. using hexane, heptane, cyclohexane, or mineral oil as the nonpolar solvent'' ** Nonpolar solvent / polar solvent / salt / water **: ''e.g. 100 ml mineral oil, 100 ml isopropanol, 75 ml water, 35 g calcium chloride'' ** Nonpolar solvent / water-soluble polymer A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mixture
In chemistry, a mixture is a material made up of two or more different chemical substances which are not chemically bonded. A mixture is the physical combination of two or more substances in which the identities are retained and are mixed in the form of Solution (chemistry), solutions, Suspension (chemistry), suspensions and colloids. Mixtures are one product of mechanically blending or mixing chemical substances such as chemical element, elements and Compound (chemistry), compounds, without chemical bonding or other chemical change, so that each ingredient substance retains its own chemical properties and makeup. Despite the fact that there are no chemical changes to its constituents, the physical properties of a mixture, such as its melting point, may differ from those of the components. Some mixtures can be separation process, separated into their components by using physical (mechanical or thermal) means. Azeotropes are one kind of mixture that usually poses considerable diffi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcium Chloride
Calcium chloride is an inorganic compound, a salt with the chemical formula . It is a white crystalline solid at room temperature, and it is highly soluble in water. It can be created by neutralising hydrochloric acid with calcium hydroxide. Calcium chloride is commonly encountered as a hydrated solid with generic formula , where ''n'' = 0, 1, 2, 4, and 6. These compounds are mainly used for de-icing and dust control. Because the anhydrous salt is hydroscopic and deliquescent, it is used as a desiccant.Robert Kemp, Suzanne E. Keegan "Calcium Chloride" in Ullmann's Encyclopedia of Industrial Chemistry 2000, Wiley-VCH, Weinheim. Uses De-icing and freezing-point depression By depressing the freezing point of water, calcium chloride is used to prevent ice formation and is used to de-ice. This application consumes the greatest amount of calcium chloride. Calcium chloride is relatively harmless to plants and soil. As a deicing agent, it is much more effective at lower temperat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aniline
Aniline is an organic compound with the formula C6 H5 NH2. Consisting of a phenyl group attached to an amino group, aniline is the simplest aromatic amine In organic chemistry, an aromatic amine is an organic compound consisting of an aromatic ring attached to an amine. It is a broad class of compounds that encompasses aniline Aniline is an organic compound with the formula C6 H5 NH2. Consi .... It is an industrially significant Commodity chemicals, commodity chemical, as well as a versatile starting material for fine chemical synthesis. Its main use is in the manufacture of precursors to polyurethane, dyes, and other industrial chemicals. Like most volatile amines, it has the odor of rotten fish. It Combustion, ignites readily, burning with a smoky flame characteristic of aromatic compounds. It is toxic to humans. Relative to benzene, it is electron-rich. It thus participates more rapidly in electrophilic aromatic substitution reactions. Likewise, it is also prone ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silicone Oil
A silicone oil is any liquid polymerized siloxane with organic side chains. The most important member is polydimethylsiloxane. These polymers are of commercial interest because of their relatively high thermal stability, lubricating, and Liquid dielectric, dielectric properties. Structure Like all siloxanes (e.g., hexamethyldisiloxane), the polymer backbone consists of alternating silicon and oxygen atoms (...Si−O−Si−O−Si...). Many groups can be attached to the tetravalent silicon centres, but the dominant substituent is methyl or sometimes phenyl. Many silicone liquids are linear polymers end-capped with trimethylsilyl groups. Other silicone liquids are cyclosiloxanes. Applications Silicone oils are primarily used as lubricants, thermic fluid oils or hydraulic fluids. They are excellent electrical insulators and, unlike their carbon analogues, are non-flammable. Their temperature stability and good heat-transfer characteristics make them widely used in laboratories for he ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ionic Liquid
An ionic liquid (IL) is a salt in the liquid state. In some contexts, the term has been restricted to salts whose melting point is below a specific temperature, such as . While ordinary liquids such as water and gasoline are predominantly made of electrically neutral molecules, ionic liquids are largely made of ions. These substances are variously called liquid electrolytes, ionic melts, ionic fluids, fused salts, liquid salts, or ionic glasses. Ionic liquids have many potential applications. They are powerful solvents and can be used as electrolytes. Salts that are liquid at near-ambient temperature are important for electric battery applications, and have been considered as sealants due to their very low vapor pressure. Any salt that melts without decomposing or vaporizing usually yields an ionic liquid. Sodium chloride (NaCl), for example, melts at into a liquid that consists largely of sodium cations () and chloride anions (). Conversely, when an ionic liquid is cooled, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1-Butyl-3-methylimidazolium Hexafluorophosphate
1-Butyl-3-methylimidazolium hexafluorophosphate, also known as BMIM-PF6, is a viscous, colourless, hydrophobic and non-water-soluble ionic liquid with a melting point of -8 °C. Together with 1-butyl-3-methylimidazolium tetrafluoroborate, BMIM-BF4, it is one of the most widely studied ionic liquids. It is known to very slowly decompose in the presence of water. Preparation BMIM-PF6 is commercially available. It may be obtained in two steps: BMIM-Cl is synthesized by alkylating 1-methylimidazole with 1-chlorobutane. A metathesis reaction with potassium hexafluorophosphate gives the desired compound; the tetrafluoroborate may be prepared by analogously using potassium tetrafluoroborate. : See also * 1-Butyl-3-methylimidazolium tetrachloroferrate 1-Butyl-3-methylimidazolium tetrachloroferrate is a magnetic ionic liquid. It can be obtained from 1-butyl-3-methylimidazolium chloride and ferric chloride. It has quite low water solubility. Due to the presence of the high spin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phase Transfer Catalyst
In chemistry, a phase-transfer catalyst or PTC is a catalyst that facilitates the transition of a reactant from one phase into another phase where reaction occurs. Phase-transfer catalysis is a special form of heterogeneous catalysis. Ionic reactants are often soluble in an aqueous phase but insoluble in an organic phase in the absence of the phase-transfer catalyst. The catalyst functions like a detergent for solubilizing the salts into the organic phase. Phase-transfer catalysis refers to the acceleration of the reaction upon the addition of the phase-transfer catalyst. By using a PTC process, one can achieve faster reactions, obtain higher conversions or yields, make fewer byproducts, eliminate the need for expensive or dangerous solvents that will dissolve all the reactants in one phase, eliminate the need for expensive raw materials and/or minimize waste problems. Phase-transfer catalysts are especially useful in green chemistry—by allowing the use of water, the nee ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aliquat 336
Aliquat 336 (Starks' catalyst) is a quaternary ammonium salt used as a phase transfer catalyst and metal extraction reagent. It contains a mixture of C8 (octyl) and C10 (decyl) chains with C8 predominating. It is an ionic liquid. Applications Organic Chemistry Aliquat 336 is used as a phase transfer catalyst, including in the catalytic oxidation of cyclohexene to 1,6-hexanedioic acid. This reaction is more environmentally friendly. It is an example of green chemistry, compared with the traditional method of oxidizing cyclohexanol or cyclohexanone with nitric acid or potassium permanganate, which produce hazardous wastes. Aliquat 336 was used in the total synthesis of manzamine A by Darren Dixon in an early step to the electrophile. Solvent extraction of metals {{Main, Liquid–liquid extraction Aliquat 336 has been used for the extraction of metals, it does so by acting as a liquid anion exchanger. It is often used while diluted in hydrocarbon solvents such as aromatic kerose ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2,2,4-Trimethylpentane
2,2,4-Trimethylpentane, also known as isooctane or iso-octane, is an organic compound with the formula (CH3)3CCH2CH(CH3)2. It is one of several isomers of octane (C8H18). This particular isomer is the standard 100 point on the octane rating scale (the zero point is ''n''-heptane). It is an important component of gasoline, frequently used in relatively large proportions (around 10%) to increase the knock resistance of fuel. Strictly speaking, if the standard meaning of ‘iso’ is followed, the name ''isooctane'' should be reserved for the isomer 2-methylheptane. However, 2,2,4-trimethylpentane is by far the most important isomer of octane and historically it has been assigned this name. Production Isooctane is produced on a massive scale in the petroleum industry by alkylation of isobutene with isobutane. This process is conducted in alkylation units in the presence of acid catalysts. It can also be produced from isobutylene by dimerization using an Amberlyst catalyst to p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrophobe
In chemistry, hydrophobicity is the physical property of a molecule that is seemingly repelled from a mass of water (known as a hydrophobe). In contrast, hydrophiles are attracted to water. Hydrophobic molecules tend to be nonpolar and, thus, prefer other neutral molecules and nonpolar solvents. Because water molecules are polar, hydrophobes do not dissolve well among them. Hydrophobic molecules in water often cluster together, forming micelles. Water on hydrophobic surfaces will exhibit a high contact angle. Examples of hydrophobic molecules include the alkanes, oils, fats, and greasy substances in general. Hydrophobic materials are used for oil removal from water, the management of oil spills, and chemical separation processes to remove non-polar substances from polar compounds. Hydrophobic is often used interchangeably with lipophilic, "fat-loving". However, the two terms are not synonymous. While hydrophobic substances are usually lipophilic, there are exceptions, suc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dichloromethane
Dichloromethane (DCM or methylene chloride, methylene bichloride) is an organochlorine compound with the formula . This colorless, volatile liquid with a chloroform-like, sweet odour is widely used as a solvent. Although it is not miscible with water, it is slightly polar, and miscible with many organic solvents.Rossberg, M. ''et al.'' (2006) "Chlorinated Hydrocarbons" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim. . Occurrence Natural sources of dichloromethane include oceanic sources, macroalgae, wetlands, and volcanoes. However, the majority of dichloromethane in the environment is the result of industrial emissions. Production DCM is produced by treating either chloromethane or methane with chlorine gas at 400–500 °C. At these temperatures, both methane and chloromethane undergo a series of reactions producing progressively more chlorinated products. In this way, an estimated 400,000 tons were produced in the US, Europe, and Japan in 1993. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Sulfate
Sodium sulfate (also known as sodium sulphate or sulfate of soda) is the inorganic compound with formula Na2SO4 as well as several related hydrates. All forms are white solids that are highly soluble in water. With an annual production of 6 million tonnes, the decahydrate is a major commodity chemical product. It is mainly used as a filler in the manufacture of powdered home laundry detergents and in the Kraft process of paper pulping for making highly alkaline sulfides. Forms *Anhydrous sodium sulfate, known as the rare mineral thenardite, used as a drying agent in organic synthesis. *Heptahydrate sodium sulfate, a very rare form. *Decahydrate sodium sulfate, known as the mineral mirabilite, widely used by chemical industry. It is also known as Glauber's salt. History The decahydrate of sodium sulfate is known as Glauber's salt after the Dutch/German chemist and apothecary Johann Rudolf Glauber (1604–1670), who discovered it in Austrian spring water in 1625. He named it (m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
