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44-607: Waxes are organic compounds that characteristically consist of long aliphatic alkyl chains, although aromatic compounds may also be present. Natural waxes may contain unsaturated bonds and include various functional groups such as fatty acids , primary and secondary alcohols , ketones , aldehydes and fatty acid esters . Synthetic waxes often consist of homologous series of long-chain aliphatic hydrocarbons ( alkanes or paraffins) that lack functional groups . Waxes are synthesized by many plants and animals. Those of animal origin typically consist of wax esters derived from

88-440: A coating for many cheeses , and to waterproof leather and fabric. Wax has been used since antiquity as a temporary, removable model in lost-wax casting of gold , silver and other materials. Wax with colorful pigments added has been used as a medium in encaustic painting , and is used today in the manufacture of crayons , china markers and colored pencils . Carbon paper , used for making duplicate typewritten documents

132-431: A flash point >500 °F (>260 °C). Many polyethylene resin plants produce a low molecular weight stream often referred to as low polymer wax (LPW). LPW is unrefined and contains volatile oligomers, corrosive catalyst and may contain other foreign material and water. Refining of LPW to produce a polyethylene wax involves removal of oligomers and hazardous catalyst. Proper refining of LPW to produce polyethylene wax

176-560: A fuel for poor people compared to higher value hard coals. In Germany, briquettes are still readily available to end consumers in home improvement stores and supermarkets. An environmentally beneficial use of lignite is in agriculture. Lignite may have value as an environmentally benign soil amendment , improving cation exchange and phosphorus availability in soils while reducing availability of heavy metals, and may be superior to commercial K humates. Lignite fly ash produced by combustion of lignite in power plants may also be valuable as

220-430: A result of increased temperatures and pressures underground. Lignite forms from peat that has not been subjected to deep burial and heating. It forms at temperatures below 100 °C (212 °F), primarily by biochemical degradation. This includes the process of humification, in which microorganisms extract hydrocarbons from peat and form humic acids, which decrease the rate of bacterial decay. In lignite, humification

264-440: A result, lignite is the most harmful coal to human health. Depending on the source, various toxic heavy metals , including naturally occurring radioactive materials , may be present in lignite and left over in the coal fly ash produced from its combustion, further increasing health risks. Lignite is brownish-black in color and has a carbon content of 60–70 percent on a dry ash-free basis. However, its inherent moisture content

308-432: A significant fraction of petroleum. They are refined by vacuum distillation . Paraffin waxes are mixtures of saturated n- and iso- alkanes , naphthenes , and alkyl - and naphthene-substituted aromatic compounds. A typical alkane paraffin wax chemical composition comprises hydrocarbons with the general formula C n H 2 n +2 , such as hentriacontane , C 31 H 64 . The degree of branching has an important influence on

352-413: A soil amendment and fertilizer. However, rigorous studies of the long-term benefits of lignite products in agriculture are lacking. Lignite may also be used for the cultivation and distribution of biological control microbes that suppress plant pests. The carbon increases the organic matter in the soil while the biological control microbes provide an alternative to chemical pesticides. Leonardite

396-413: A variety of fatty acids and carboxylic alcohols. In waxes of plant origin, characteristic mixtures of unesterified hydrocarbons may predominate over esters. The composition depends not only on species, but also on geographic location of the organism. The best-known animal wax is beeswax , used in constructing the honeycombs of beehives, but other insects also secrete waxes. A major component of beeswax

440-921: Is a fossilized wax extracted from coal and lignite . It is very hard, reflecting the high concentration of saturated fatty acids and alcohols. Although dark brown and odorous, they can be purified and bleached to give commercially useful products. As of 1995, about 200 million kilograms of polyethylene waxes were consumed annually. Polyethylene waxes are manufactured by one of three methods: Each production technique generates products with slightly different properties. Key properties of low molecular weight polyethylene waxes are viscosity, density and melt point. Polyethylene waxes produced by means of degradation or recovery from polyethylene resin streams contain very low molecular weight materials that must be removed to prevent volatilization and potential fire hazards during use. Polyethylene waxes manufactured by this method are usually stripped of low molecular weight fractions to yield

484-563: Is a soil conditioner rich in humic acids that is formed by natural oxidation when lignite comes in contact with air. The process can be replicated artificially on a large scale. The less matured xyloid (wood-shaped) lignite also contains high amounts of humic acid. Reaction with quaternary amine forms a product called amine-treated lignite (ATL), which is used in drilling mud to reduce fluid loss during drilling. Lignite may have potential uses as an industrial adsorbent . Experiments show that its adsorption of methylene blue falls within

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528-536: Is called slacking or slackening . Most lignite is used to generate electricity. However, small amounts are used in agriculture , in industry , and even, as jet , in jewelry . Its historical use as fuel for home heating has continuously declined and is now of lower importance than its use to generate electricity. Lignite is often found in thick beds located near the surface, making it inexpensive to mine. However, because of its low energy density , tendency to crumble, and typically high moisture content, brown coal

572-454: Is especially important when being used in applications requiring FDA or other regulatory certification. Waxes are mainly consumed industrially as components of complex formulations, often for coatings. The main use of polyethylene and polypropylene waxes is in the formulation of colourants for plastics. Waxes confer matting effects (i.e., to confer non-glossy finishes) and wear resistance to paints. Polyethylene waxes are incorporated into inks in

616-869: Is frequently used as a lubricant on drawer slides where wood to wood contact occurs. Sealing wax was used to close important documents in the Middle Ages . Wax tablets were used as writing surfaces. There were different types of wax in the Middle Ages, namely four kinds of wax ( Ragusan , Montenegro , Byzantine , and Bulgarian ), "ordinary" waxes from Spain , Poland , and Riga , unrefined waxes and colored waxes (red, white, and green). Waxes are used to make waxed paper , impregnating and coating paper and card to waterproof it or make it resistant to staining, or to modify its surface properties. Waxes are also used in shoe polishes , wood polishes , and automotive polishes, as mold release agents in mold making , as

660-734: Is inefficient to transport and is not traded extensively on the world market compared with higher coal grades. It is often burned in power stations near the mines, such as in Poland's Bełchatów plant and Turów plant , Australia's Latrobe Valley and Luminant 's Monticello plant and Martin Lake plant in Texas. Primarily because of latent high moisture content and low energy density of brown coal, carbon dioxide emissions from traditional brown-coal-fired plants are generally much higher per megawatt-hour generated than for comparable black-coal plants, with

704-424: Is myricyl palmitate which is an ester of triacontanol and palmitic acid . Its melting point is 62–65 °C (144–149 °F). Spermaceti occurs in large amounts in the head oil of the sperm whale . One of its main constituents is cetyl palmitate , another ester of a fatty acid and a fatty alcohol . Lanolin is a wax obtained from wool, consisting of esters of sterols . Plants secrete waxes into and on

748-492: Is partial, coming to completion only when the coal reaches sub-bituminous rank. The most characteristic chemical change in the organic material during formation of lignite is the sharp reduction in the number of C=O and C-O-R functional groups. Lignite deposits are typically younger than higher-ranked coals, with the majority of them having formed during the Tertiary period. Lignite is often found in thick beds located near

792-463: Is sometimes as high as 75 percent and its ash content ranges from 6–19 percent, compared with 6–12 percent for bituminous coal . As a result, its carbon content on the as-received basis (i.e., containing both inherent moisture and mineral matter) is typically just 25-35 percent. The energy content of lignite ranges from 10 to 20 MJ/kg (9–17 million BTU per short ton ) on a moist, mineral-matter-free basis. The energy content of lignite consumed in

836-473: The carbon chain , the most common being oxygen , nitrogen , sulfur , and chlorine , it is no longer a hydrocarbon, and therefore no longer an aliphatic compound. However, such compounds may still be referred to as aliphatic if the hydrocarbon portion of the molecule is aliphatic, e.g. aliphatic amines , to differentiate them from aromatic amines . The least complex aliphatic compound is methane (CH 4 ). Most aliphatic compounds are flammable , allowing

880-434: The lowest rank of coal due to its relatively low heat content . When removed from the ground, it contains a very high amount of moisture , which partially explains its low carbon content. Lignite is mined all around the world and is used almost exclusively as a fuel for steam-electric power generation . Lignite combustion produces less heat for the amount of carbon dioxide and sulfur released than other ranks of coal. As

924-596: The railway network was dependent on lignite either through steam trains or electrified lines mostly fed with lignite derived power. As per the table below, East Germany was the largest producer of lignite for much of its existence as an independent state. In 2014, about 12 percent of Germany's energy and, specifically, 27 percent of Germany's electricity came from lignite power plants, while in 2014 in Greece , lignite provided about 50 percent of its power needs. Germany has announced plans to phase out lignite by 2038 at

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968-527: The Brazilian palm Copernicia prunifera . Containing the ester myricyl cerotate, it has many applications, such as confectionery and other food coatings, car and furniture polish, floss coating, and surfboard wax . Other more specialized vegetable waxes include jojoba oil , candelilla wax and ouricury wax . Plant and animal based waxes or oils can undergo selective chemical modifications to produce waxes with more desirable properties than are available in

1012-585: The C-C bonds are single requiring the structure to be completed, or 'saturated', by hydrogen) like hexane , or unsaturated , like hexene and hexyne . Open-chain compounds , whether straight or branched, and which contain no rings of any type, are always aliphatic. Cyclic compounds can be aliphatic if they are not aromatic . Aliphatic compounds can be saturated , joined by single bonds ( alkanes ), or unsaturated, with double bonds ( alkenes ) or triple bonds ( alkynes ). If other elements ( heteroatoms ) are bound to

1056-654: The United States averages 15 MJ/kg (13 million BTU/ton), on the as-received basis. The energy content of lignite consumed in Victoria, Australia, averages 8.6 MJ/kg (8.2 million BTU/ton) on a net wet basis. Lignite has a high content of volatile matter which makes it easier to convert into gas and liquid petroleum products than higher-ranking coals. Its high moisture content and susceptibility to spontaneous combustion can cause problems in transportation and storage. Processes which remove water from brown coal reduce

1100-420: The area remains saturated with water, which covers dead vegetation and protects it from atmospheric oxygen. Otherwise, peat swamps are found in a variety of climates and geographical settings. Anaerobic bacteria may contribute to the degradation of peat, but this process takes a long time, particularly in acidic water. Burial by other sediments further slows biological degradation, and subsequent transformations are

1144-491: The form of dispersions to decrease friction. They are employed as release agents , find use as slip agents in furniture, and confer corrosion resistance. Waxes such as paraffin wax or beeswax , and hard fats such as tallow are used to make candles , used for lighting and decoration. Another fuel type used in candle manufacturing includes soy . Soy wax is made by the hydrogenation process using soybean oil. Waxes are used as finishes and coatings for wood products. Beeswax

1188-931: The governments of Japan and Australia has begun extracting hydrogen from brown coal. The liquefied hydrogen will be shipped via the transporter Suiso Frontier to Japan. The largest lignite deposits in North America are the Gulf Coast lignites and the Fort Union lignite field. The Gulf Coast lignites are located in a band running from Texas to Alabama roughly parallel to the Gulf Coast. The Fort Union lignite field stretches from North Dakota to Saskatchewan . Both are important commercial sources of lignite. Lignite can be separated into two types: xyloid lignite or fossil wood , and compact lignite or perfect lignite. Although xyloid lignite may sometimes have

1232-881: The land has been restored to full productivity. A bond (not necessary in this form) for mine reclamation is required in the US by the Surface Mining Control and Reclamation Act of 1977 . The Latrobe Valley in Victoria , Australia , contains estimated reserves of some 65 billion tonnes of brown coal. The deposit is equivalent to 25 percent of known world reserves. The coal seams are up to 98 m (322 ft) thick, with multiple coal seams often giving virtually continuous brown coal thickness of up to 230 m (755 ft). Seams are covered by very little overburden (10 to 20 m (33 to 66 ft)). A partnership led by Kawasaki Heavy Industries and backed by

1276-473: The latest. Greece has confirmed that the last coal plant will be shut in 2025 after receiving pressure from the European Union and plans to heavily invest in renewable energy . Lignite was and is used as a replacement for or in combination with firewood for home heating. It is usually pressed into briquettes for that use. Due to the smell it gives off when burned, lignite was often seen as

1320-407: The lignite is removed, restoration involves grading the mine spoil to as close an approximation as practical of the original ground surface (Approximate Original Contour or AOC). Subsoil and topsoil are restored and the land reseeded with various grasses. In North Dakota , a performance bond is held against the mining company for at least ten years after the end of mining operations to guarantee that

1364-410: The list below (sorted by the number of carbon-atoms): This organic chemistry article is a stub . You can help Misplaced Pages by expanding it . Lignite Lignite (derived from Latin lignum meaning 'wood'), often referred to as brown coal , is a soft, brown, combustible sedimentary rock formed from naturally compressed peat . It has a carbon content around 25–35% and is considered

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1408-870: The performance. Some waxes are considered food-safe and are used to coat wooden cutting boards and other items that come into contact with food. Beeswax or coloured synthetic wax is used to decorate Easter eggs in Romania, Ukraine, Poland, Lithuania and the Czech Republic. Paraffin wax is used in making chocolate covered sweets. Wax is also used in wax bullets , which are used as simulation aids, and for wax sculpturing . Aliphatic In organic chemistry , hydrocarbons ( compounds composed solely of carbon and hydrogen ) are divided into two classes: aromatic compounds and aliphatic compounds ( / ˌ æ l ɪ ˈ f æ t ɪ k / ; G. aleiphar , fat, oil). Aliphatic compounds can be saturated (in which all

1452-404: The properties. Microcrystalline wax is a lesser produced petroleum based wax that contains higher percentage of isoparaffinic (branched) hydrocarbons and naphthenic hydrocarbons. Millions of tons of paraffin waxes are produced annually. They are used in foods (such as chewing gum and cheese wrapping), in candles and cosmetics, as non-stick and waterproofing coatings and in polishes. Montan wax

1496-746: The range of activated carbons currently used by industry. Jet is a form of lignite that has been used as a gemstone. The earliest jet artifacts date to 10,000 BCE and jet was used extensively in necklaces and other ornamentation in Britain from the Neolithic until the end of Roman Britain . Jet experienced a brief revival in Victorian Britain . Lignite begins as partially decayed plant material, or peat. Peat tends to accumulate in areas with high moisture, slow land subsidence , and no disturbance by rivers or oceans – under these conditions,

1540-414: The risk of spontaneous combustion to the same level as black coal, increase the calorific value of brown coal to a black coal equivalent fuel, and significantly reduce the emissions profile of 'densified' brown coal to a level similar to or better than most black coals. However, removing the moisture increases the cost of the final lignite fuel. Lignite rapidly degrades when exposed to air. This process

1584-422: The subsurface beds. Topsoil and subsoil must be properly removed and either used to reclaim previously mined-out areas or stored for future reclamation. Excavator and truck overburden removal prepares the area for dragline overburden removal to expose the lignite beds. These are broken up using specially equipped tractors ( coal ripping ) and then loaded into bottom dump trucks using front loaders . Once

1628-406: The surface of their cuticles as a way to control evaporation, wettability and hydration. The epicuticular waxes of plants are mixtures of substituted long-chain aliphatic hydrocarbons, containing alkanes, alkyl esters, fatty acids, primary and secondary alcohols, diols , ketones and aldehydes. From the commercial perspective, the most important plant wax is carnauba wax , a hard wax obtained from

1672-409: The surface. These are inexpensive to extract using various forms of surface mining , though this can result in serious environmental damage. Regulations in the United States and other countries require that land that is surface mined must be restored to its original productivity once mining is complete. Strip mining of lignite in the United States begins with drilling to establish the extent of

1716-401: The tenacity and the appearance of ordinary wood, it can be seen that the combustible woody tissue has experienced a great modification. It is reducible to a fine powder by trituration , and if submitted to the action of a weak solution of potash , it yields a considerable quantity of humic acid . Leonardite is an oxidized form of lignite, which also contains high levels of humic acid. Jet

1760-407: The unmodified starting material. This approach has relied on green chemistry approaches including olefin metathesis and enzymatic reactions and can be used to produce waxes from inexpensive starting materials like vegetable oils. Although many natural waxes contain esters, paraffin waxes are hydrocarbons, mixtures of alkanes usually in a homologous series of chain lengths. These materials represent

1804-442: The use of hydrocarbons as fuel , such as methane in natural gas for stoves or heating; butane in torches and lighters ; various aliphatic (as well as aromatic) hydrocarbons in liquid transportation fuels like petrol/gasoline , diesel , and jet fuel ; and other uses such as ethyne (acetylene) in welding . The most important aliphatic compounds are: Important examples of low-molecular aliphatic compounds can be found in

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1848-501: The world's highest-emitting plant being Australia's Hazelwood Power Station until its closure in March 2017. The operation of traditional brown-coal plants, particularly in combination with strip mining , is politically contentious due to environmental concerns. The German Democratic Republic relied extensively on lignite to become energy self-sufficient , and eventually obtained 70% of its energy requirements from lignite. Lignite

1892-496: Was also an important chemical industry feedstock via Bergius process or Fischer-Tropsch synthesis in lieu of petroleum, which had to be imported for hard currency following a change in policy by the Soviet Union in the 1970s, which had previously delivered petroleum at below market rates. East German scientists even converted lignite into coke suitable for metallurgical uses ( high temperature lignite coke ) and much of

1936-439: Was coated with carbon black suspended in wax, typically montan wax , but has largely been superseded by photocopiers and computer printers . In another context, lipstick and mascara are blends of various fats and waxes colored with pigments, and both beeswax and lanolin are used in other cosmetics . Ski wax is used in skiing and snowboarding . Also, the sports of surfing and skateboarding often use wax to enhance

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