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Dry Distillation
Dry distillation is the heating of solid materials to produce gaseous products (which may condense into liquids or solids). The method may involve pyrolysis or thermolysis, or it may not (for instance, a simple mixture of ice and glass could be separated without breaking any chemical bonds, but organic matter contains a greater diversity of molecules, some of which are likely to break). If there are no chemical changes, just phase changes, it resembles classical distillation, although it will generally need higher temperatures. Dry distillation in which chemical changes occur is a type of destructive distillation or cracking. Uses The method has been used to obtain liquid fuels from coal and wood. It can also be used to break down mineral salts such as sulfates () through thermolysis, in this case producing sulfur dioxide (SO2) or sulfur trioxide (SO3) gas which can be dissolved in water to obtain sulfuric acid. By this method sulfuric acid was first identified and artificiall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Resin
In polymer chemistry and materials science, resin is a solid or highly viscous substance of plant or synthetic origin that is typically convertible into polymers. Resins are usually mixtures of organic compounds. This article focuses on naturally occurring resins. Plants secrete resins for their protective benefits in response to injury. The resin protects the plant from insects and pathogens. Resins confound a wide range of herbivores, insects, and pathogens, while the volatile phenolic compounds may attract benefactors such as parasitoids or predators of the herbivores that attack the plant. Composition Most plant resins are composed of terpenes. Specific components are alpha-pinene, beta-pinene, delta-3 carene, and sabinene, the monocyclic terpenes limonene and terpinolene, and smaller amounts of the tricyclic sesquiterpenes, longifolene, caryophyllene, and delta-cadinene. Some resins also contain a high proportion of resin acids. Rosins on the other hand are less ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulfuric Acid
Sulfuric acid (American spelling and the preferred IUPAC name) or sulphuric acid ( Commonwealth spelling), known in antiquity as oil of vitriol, is a mineral acid composed of the elements sulfur, oxygen and hydrogen, with the molecular formula . It is a colorless, odorless and viscous liquid that is miscible with water. Pure sulfuric acid does not exist naturally on Earth due to its strong affinity to water vapor; it is hygroscopic and readily absorbs water vapor from the air. Concentrated sulfuric acid is highly corrosive towards other materials, from rocks to metals, since it is an oxidant with powerful dehydrating properties. Phosphorus pentoxide is a notable exception in that it is not dehydrated by sulfuric acid, but to the contrary dehydrates sulfuric acid to sulfur trioxide. Upon addition of sulfuric acid to water, a considerable amount of heat is released; thus the reverse procedure of adding water to the acid should not be performed since the heat released may boi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methanol
Methanol (also called methyl alcohol and wood spirit, amongst other names) is an organic chemical and the simplest aliphatic alcohol, with the formula C H3 O H (a methyl group linked to a hydroxyl group, often abbreviated as MeOH). It is a light, volatile, colourless, flammable liquid with a distinctive alcoholic odour similar to that of ethanol (potable alcohol). A polar solvent, methanol acquired the name wood alcohol because it was once produced chiefly by the destructive distillation of wood. Today, methanol is mainly produced industrially by hydrogenation of carbon monoxide. Methanol consists of a methyl group linked to a polar hydroxyl group. With more than 20 million tons produced annually, it is used as a precursor to other commodity chemicals, including formaldehyde, acetic acid, methyl tert-butyl ether, methyl benzoate, anisole, peroxyacids, as well as a host of more specialised chemicals. Occurrence Small amounts of methanol are present in normal, healthy hu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deciduous
In the fields of horticulture and Botany, the term ''deciduous'' () means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed leaves, usually in the autumn; to the shedding of petals, after flowering; and to the shedding of ripe fruit. The antonym of ''deciduous'' in the botanical sense is evergreen. Generally, the term "deciduous" means "the dropping of a part that is no longer needed or useful" and the "falling away after its purpose is finished". In plants, it is the result of natural processes. "Deciduous" has a similar meaning when referring to animal parts, such as deciduous antlers in deer, deciduous teeth (baby teeth) in some mammals (including humans); or decidua, the uterine lining that sheds off after birth. Botany In botany and horticulture, deciduous plants, including trees, shrubs and herbaceous perennials, are those that lose all of their leaves for part of the year. This process is called abscissio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyroligneous Acid
Pyroligneous acid, also called wood vinegar or wood acid, is a dark liquid produced by the destructive distillation of wood and other plant material Composition The principal components of pyroligneous acid are 10% acetic acid, acetone and methanol. It was once used as a commercial source for acetic acid. History Pyroligneous acid (acetum lignorum) was investigated by German chemist Johann Rudolph Glauber. The acid was used as a substitute for vinegar. It was also used topically for treating wounds, ulcers and other ailments. A salt can be made by neutralizing the acid with a lye made from the ashes of the burnt wood. During the United States Civil War it became increasingly difficult for the Confederate States of America to obtain much needed salt. Curing meat and fish with pyroligneous acid was attempted by cooks to compensate for this deficiency, but it was insufficient. In the nineteenth century, pyroligneous acid was used to prepare an impure aluminium sulfacetate mordan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charcoal Burning
A charcoal burner is someone whose occupation is to manufacture charcoal. Traditionally this is achieved by carbonising wood in a charcoal pile or kiln. Charcoal burning is one of the oldest human crafts. The knowledge gained from this industry still contributes to the solution of energy problems today. Due to its historical and cultural importance, charcoal burning and tar distilling were incorporated in December 2014 into the register of the Intangible Cultural Heritage in Germany by the ''Kultusministerkonferenz''. History and technique Medieval charcoal burners Since the Iron Age, high temperatures have had to be produced for iron smelting, for glassmaking, and for the working of precious metals. Charcoal has been used to do this for centuries and, in order to produce it, entire forests were felled. With the increasing use of stone coal from the 18th century, the charcoal burning industry declined. Even in ancient times, charcoal was manufactured in kilns. Logs were ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coal Tar
Coal tar is a thick dark liquid which is a by-product of the production of coke and coal gas from coal. It is a type of creosote. It has both medical and industrial uses. Medicinally it is a topical medication applied to skin to treat psoriasis and seborrheic dermatitis (dandruff). It may be used in combination with ultraviolet light therapy. Industrially it is a railroad tie preservative and used in the surfacing of roads. Coal tar was listed as a known human carcinogen in the first Report on Carcinogens from the U.S. Federal Government. Coal tar was discovered circa 1665 and used for medical purposes as early as the 1800s. Circa 1850, the discovery that it could be used as the main ingredient in synthetic dyes engendered an entire industry. It is on the World Health Organization's List of Essential Medicines. Coal tar is available as a generic medication and over the counter. Side effects include skin irritation, sun sensitivity, allergic reactions, and skin discoloration. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coal Gas
Coal gas is a flammable gaseous fuel made from coal and supplied to the user via a piped distribution system. It is produced when coal is heated strongly in the absence of air. Town gas is a more general term referring to manufactured gaseous fuels produced for sale to consumers and municipalities. The original coal gas was produced by the coal gasification reaction, and thus the burnable component consisted of a roughly equal molecular mixture of carbon monoxide and hydrogen. Thus, coal gas was highly toxic. Other compositions contain additional calorific gases such as methane, produced by the Fischer-Tropsch process, and volatile hydrocarbons together with small quantities of non-calorific gases such as carbon dioxide and nitrogen. Prior to the development of natural gas supply and transmission—during the 1940s and 1950s in the United States and during the late 1960s and 1970s in the United Kingdom and Australia—almost all gas for fuel and lighting was manufactured fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coal Gasification
Coal gasification is the process of producing syngas—a mixture consisting primarily of carbon monoxide (CO), hydrogen (H2), carbon dioxide (CO2), methane (CH4), and water vapour (H2O)—from coal and water, air and/or oxygen. Historically, coal was gasified to produce coal gas, also known as "town gas". Coal gas is combustible and was used for heating and municipal lighting, before the advent of large-scale extraction of natural gas from oil wells. In current practice, large-scale coal gasification installations are primarily for electricity generation (both in conventional thermal power stations and molten carbonate fuel cell power stations), or for production of chemical feedstocks. The hydrogen obtained from coal gasification can be used for various purposes such as making ammonia, powering a hydrogen economy, or upgrading fossil fuels. Alternatively, coal-derived syngas can be converted into transportation fuels such as gasoline and diesel through additional treatment, or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbonization
Carbonization is the conversion of organic matters like plants and dead animal remains into carbon through destructive distillation. Complexity in carbonization Carbonization is a pyrolytic reaction, therefore, is considered a complex process in which many reactions take place concurrently such as dehydrogenation, condensation, hydrogen transfer and isomerization. Carbonization differs from coalification in that it occurs much faster, due to its reaction rate being faster by many orders of magnitude. For the final pyrolysis temperature, the amount of heat applied controls the degree of carbonization and the residual content of foreign elements. For example, at T ~ 1200 K the carbon content of the residue exceeds a mass fraction of 90 wt.%, whereas at T ~ 1600 K more than 99 wt.% carbon is found. Carbonization is often exothermic, which means that it could in principle be made self-sustaining and be used as a source of energy that does not produce carbon dioxide. In the case ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charcoal
Charcoal is a lightweight black carbon residue produced by strongly heating wood (or other animal and plant materials) in minimal oxygen to remove all water and volatile constituents. In the traditional version of this pyrolysis process, called charcoal burning, often by forming a charcoal kiln, the heat is supplied by burning part of the starting material itself, with a limited supply of oxygen. The material can also be heated in a closed retort. Modern "charcoal" briquettes used for outdoor cooking may contain many other additives, e.g. coal. This process happens naturally when combustion is incomplete, and is sometimes used in radiocarbon dating. It also happens inadvertently while burning wood, as in a fireplace or wood stove. The visible flame in these is due to combustion of the volatile gases exuded as the wood turns into charcoal. The soot and smoke commonly given off by wood fires result from incomplete combustion of those volatiles. Charcoal burns at a higher temper ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coke (fuel)
Coke is a grey, hard, and porous coal-based fuel with a high carbon content and few impurities, made by heating coal or oil in the absence of air—a destructive distillation process. It is an important industrial product, used mainly in iron ore smelting, but also as a fuel in stoves and forges when air pollution is a concern. The unqualified term "coke" usually refers to the product derived from low-ash and low-sulphur bituminous coal by a process called coking. A similar product called petroleum coke, or pet coke, is obtained from crude oil in oil refineries. Coke may also be formed naturally by geologic processes.B. Kwiecińska and H. I. Petersen (2004): "Graphite, semi-graphite, natural coke, and natural char classification — ICCP system". ''International Journal of Coal Geology'', volume 57, issue 2, pages 99-116. History China Historical sources dating to the 4th century describe the production of coke in ancient China. The Chinese first used coke for heating ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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