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Raffinate
In chemical separation terminology, the raffinate (from French ''raffiner'', to refine) is a product which has had a component or components removed. The product having the removed materials is referred to as the extract. For example, in solvent extraction, the raffinate is the liquid stream which remains after solutes from the original liquid are removed through contact with an immiscible liquid. In metallurgy, raffinating refers to a process in which impurities are removed from liquid material. In pressure swing adsorption the raffinate refers to the gas which is not adsorbed during the high pressure stage. The species which is desorbed from the adsorbent at low pressure may be called the "extract" product. Types Raffinate-1 or C4R1 In naphtha cracking process, C4R1 refers to C4 residual obtained after separation of 1,3-butadiene from C4 raffinate stream and which, mainly consists of isobutylene 40~50 wt% and ''cis''- or ''trans''-2-butene 30~35 wt%. Normally C4R1 is a side pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extract
An extract is a substance made by extracting a part of a raw material, often by using a solvent such as ethanol, oil or water. Extracts may be sold as tinctures, absolutes or in powder form. The aromatic principles of many spices, nuts, herbs, fruits, etc., and some flowers, are marketed as extracts, among the best known of true extracts being almond, cinnamon, cloves, ginger, lemon, nutmeg, orange, peppermint, pistachio, rose, spearmint, vanilla, violet, rum, and wintergreen. Extraction techniques Most natural essences are obtained by extracting the essential oil from the feedstock, such as blossoms, fruit, and roots, or from intact plants through multiple techniques and methods: * Expression (juicing, pressing) involves physical extraction material from feedstock, used when the oil is plentiful and easily obtained from materials such as citrus peels, olives, and grapes. * Absorption (steeping, decoction). Extraction is done by soaking material in a solvent, as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solvent Extraction
A solvent (s) (from the Latin '' solvō'', "loosen, untie, solve") 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. Water is a solvent for polar molecules and the most common solvent used by living things; all the ions and proteins in a cell are dissolved in water within the cell. 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, and 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 syn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Miscibility
Miscibility () is the property of two substances to mix in all proportions (that is, to fully dissolve in each other at any concentration), forming a homogeneous mixture (a solution). The term is most often applied to liquids but also applies to solids and gases. For example, water and ethanol are miscible because they mix in all proportions. By contrast, substances are said to be immiscible if there are certain proportions in which the mixture does not form a solution. For one example, oil is not soluble in water, so these two solvents are immiscible. As another example, butanone (methyl ethyl ketone) is significantly soluble in water, but these two solvents are also immiscible because in some proportions the mixture will separate into two phases. Organic compounds In organic compounds, the weight percent of hydrocarbon chain often determines the compound's miscibility with water. For example, among the alcohols, ethanol has two carbon atoms and is miscible with water, w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pressure Swing Adsorption
Pressure swing adsorption (PSA) is a technique used to separate some gas species from a mixture of gases (typically air) under pressure according to the species' molecular characteristics and affinity for an adsorbent material. It operates at near-ambient temperature and significantly differs from the cryogenic distillation commonly used to separate gases. Selective adsorbent materials (e.g., zeolites, (aka molecular sieves), activated carbon, etc.) are used as trapping material, preferentially adsorbing the target gas species at high pressure. The process then swings to low pressure to desorb the adsorbed gas. Process Pressure swing adsorption process (PSA) is based on the phenomenon that under high pressure, gases tend to be trapped onto solid surfaces, ''i.e.'', to be "adsorbed". The higher the pressure, the more gas is adsorbed. When the pressure is dropped, the gas is released, or desorbed. PSA can be used to separate gases in a mixture because different gases are adsorbe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluid Catalytic Cracking
Fluid Catalytic Cracking (FCC) is the conversion process used in petroleum refineries to convert the high-boiling point, high-molecular weight hydrocarbon fractions of petroleum (crude oils) into gasoline, olefinic gases, and other petroleum products. The cracking of petroleum hydrocarbons was originally done by thermal cracking, now virtually replaced by catalytic cracking, which yields greater volumes of high octane rating gasoline; and produces by-product gases, with more carbon-carbon double bonds (i.e. olefins), that are of greater economic value than the gases produced by thermal cracking. The feedstock to the FCC conversion process usually is heavy gas oil (HGO), which is that portion of the petroleum (crude oil) that has an initial boiling-point temperature of or higher, at atmospheric pressure, and that has an average molecular weight that ranges from about 200 to 600 or higher; heavy gas oil also is known as “heavy vacuum gas oil” (HVGO). In the fluid catalytic cra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1,3-butadiene
1,3-Butadiene () is the organic compound with the formula (CH2=CH)2. It is a colorless gas that is easily condensed to a liquid. It is important industrially as a precursor to synthetic rubber. The molecule can be viewed as the union of two vinyl groups. It is the simplest conjugated diene. Although butadiene breaks down quickly in the atmosphere, it is nevertheless found in ambient air in urban and suburban areas as a consequence of its constant emission from motor vehicles. The name butadiene can also refer to the isomer, 1,2-butadiene, which is a cumulated diene with structure H2C=C=CH−CH3. This allene has no industrial significance. History In 1863, the French chemist E. Caventou isolated butadiene from the pyrolysis of amyl alcohol. This hydrocarbon was identified as butadiene in 1886, after Henry Edward Armstrong isolated it from among the pyrolysis products of petroleum. In 1910, the Russian chemist Sergei Lebedev polymerized butadiene and obtained a material wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isobutylene
Isobutylene (or 2-methylpropene) is a hydrocarbon with the chemical formula . It is a four-carbon branched alkene (olefin), one of the four isomers of butylene. It is a colorless flammable gas, and is of considerable industrial value. Production Polymer and chemical grade isobutylene is typically obtained by dehydrating tertiary butyl alcohol (TBA) or catalytic dehydrogenation of isobutane (Catofin or similar processes).. Gasoline additives methyl tert-butyl ether (MTBE) and ethyl tert-butyl ether (ETBE), respectively, are produced by reacting methanol or ethanol with isobutylene contained in butene streams from olefin steam crackers or refineries, or with isobutylene from dehydrated TBA. Isobutylene is not isolated from the olefin or refinery butene stream before the reaction, as separating the ethers from the remaining butenes is simpler. Isobutylene can also be produced in high purities by "back-cracking" MTBE or ETBE at high temperatures and then separating the isobutylene by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2-butene
But-2-ene is an acyclic alkene with four carbon atoms. It is the simplest alkene exhibiting ''cis''/''trans''-isomerism (also known as (''E''/''Z'')-isomerism); that is, it exists as two geometric isomers ''cis''-but-2-ene ((''Z'')-but-2-ene) and ''trans-''but-2-ene ((''E'')-but-2-ene). It is a petrochemical, produced by the catalytic cracking of crude oil or the dimerization of ethylene. Its main uses are in the production of gasoline (petrol) and butadiene,. although some but-2-ene is also used to produce the solvent butanone via hydration to 2-butanol followed by oxidation. The two isomers are extremely difficult to separate by distillation because of the proximity of their boiling points (~4 °C for ''cis'' and ~1 °C for ''trans'' ) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tert-Butyl Alcohol
''tert''-Butyl alcohol is the simplest tertiary alcohol, with a formula of (CH3)3COH (sometimes represented as ''t''-BuOH). Its isomers are 1-butanol, isobutanol, and butan-2-ol. ''tert''-Butyl alcohol is a colorless solid, which melts near room temperature and has a camphor-like odor. It is miscible with water, ethanol and diethyl ether. Natural occurrence ''tert''-Butyl alcohol has been identified in beer and chickpeas. It is also found in cassava, which is used as a fermentation ingredient in certain alcoholic beverages. Preparation ''tert''-Butyl alcohol is derived commercially from isobutane as a coproduct of propylene oxide production. It can also be produced by the catalytic hydration of isobutylene, or by a Grignard reaction between acetone and methylmagnesium chloride. Purification cannot be performed by simple distillation due to formation of an azeotrope with water, although initial drying of the solvent containing large amounts of water is performed by adding benz ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1-butene
1-Butene (or 1-Butylene) is the organic compound with the formula CH3CH2CH=CH2. It is a colorless gas that is easily condensed to give a colorless liquid. It is classified as a linear alpha-olefin. It is one of the isomers of butene (butylene). It is a precursor to diverse products. Reactions Polymerization of 1-butene give polybutene, which is used to make piping for domestic plumbing. Its main application is as a comonomer in the production of certain kinds of polyethylene, such as linear low-density polyethylene (LLDPE). It has also been used as a precursor to polypropylene resins, butylene oxide, and butanone. Manufacturing 1-Butene is produced by separation from crude C4 refinery streams and by ethylene dimerization. The former affords a mixture of 1-and 2-butenes, while the latter affords only the terminal alkene. It is distilled to give a very high purity product. An estimated 12 billion kilograms were produced in 2011. See also *Butene *Dimer (chemistry) *Octene Oct ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Butane
Butane () or ''n''-butane is an alkane with the formula C4H10. Butane is a gas at room temperature and atmospheric pressure. Butane is a highly flammable, colorless, easily liquefied gas that quickly vaporizes at room temperature. The name butane comes from the root but- (from butyric acid, named after the Greek word for butter) and the suffix -ane. It was discovered by the chemist Dr. Walter Snelling in 1912. It was found dissolved in crude petroleum in 1864 by Edmund Ronalds, who was the first to describe its properties. Butane is one of a group of liquefied petroleum gases (LP gases). The others include propane, propylene, butadiene, butylene, isobutylene, and mixtures thereof. Butane burns more cleanly than gasoline and coal. Density The density of butane is highly dependent on temperature and pressure in the reservoir. For example, the density of liquid phase is 571.8±1 kg/m3 (for pressures up to 2MPa and temperature 27±0.2 °C), while the density of liq ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
