1.
Carbonization
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Carbonization is the term for the conversion of an organic substance into carbon or a carbon-containing residue through pyrolysis or destructive distillation. It is often used in chemistry with reference to the generation of coal gas. Fossil fuels generally are the products of the carbonization of vegetable matter, the term carbonization is also applied to the pyrolysis of coal to produce coke. In the wool processing industry, carbonising is the name for a process by which vegetable matter is removed from wool. Carbonization differs from coalification in that it much faster, due to its reaction rate being faster by many orders of magnitude. For the final temperature, the amount of heat applied controls the degree of carbonization. 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, in the case of glucose, the reaction releases about 237 calories per gram. When biomaterial is exposed to sudden searing heat, it can be carbonized extremely quickly, in the destruction of Herculaneum by a volcano, many organic objects such as furniture were carbonized by the intense heat. The carbonization of wood in a setting usually requires a temperature above 280°C. This carbonization, which can also be seen as a breakdown of the wood. Unless further external heat is provided, the stops and the temperature reaches a maximum of about 400°C. This charcoal, however, will still contain appreciable amounts of tarry residue, carbonisation produces substances which can prove harmful and simple precautions should be taken to reduce risks. The gas produced by carbonization has a content of carbon monoxide which is poisonous when breathed. The tars and smoke produced from carbonization, although not directly poisonous, the tars and pyroligneous liquors can also seriously contaminate streams and affect drinking water supplies for humans and animals. Fish may also be adversely affected, fortunately kilns and pits, as distinct from retorts and other sophisticated systems, do not normally produce liquid effluent - the by-products are mostly dispersed into the air as vapours. Precautions against airborne contamination of the environment are of importance in this case. In one study, carbonization was used to create a new catalyst for the generation of biodiesel from ethanol, the catalyst was created by carbonization of simple sugars such as glucose and sucrose
2.
Carburetor
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A carburetor, or carburettor, or carburator, or carburetter is a device that blends air and fuel for an internal combustion engine in the proper ratio for combustion. It is sometimes shortened to carb in North America or carby in Australia. To carburate or carburet is to blend the air and fuel or to equip with a carburetor for that purpose, carburetors have largely been supplanted in the automotive and, to a lesser extent, aviation industries by fuel injection. They are still common on engines for lawn mowers, rototillers. The word carburetor comes from the French carbure meaning carbide, carburer means to combine with carbon. In fuel chemistry, the term has the specific meaning of increasing the carbon content of a fluid by mixing it with a volatile hydrocarbon. The first carburetor was invented by Samuel Morey in 1826, a carburetor was invented by an Italian, Luigi De Cristoforis, in 1876. Another carburetor was developed by Enrico Bernardi at the University of Padua in 1882, for his Motrice Pia, a carburetor was among the early patents by Karl Benz as he developed internal combustion engines and their components. Early carburetors were the surface type, in which air is charged with fuel by being passed over the surface of gasoline. In 1885, Wilhelm Maybach and Gottlieb Daimler developed a float carburetor for their engine based on the atomizer nozzle, hungarian engineers János Csonka and Donát Bánki patented a carburetor for a stationary engine in 1893. Frederick William Lanchester of Birmingham, England, experimented with the wick carburetor in cars, in 1896, Frederick and his brother built the first gasoline-driven car in England, a single cylinder 5 hp internal combustion engine with chain drive. Unhappy with the performance and power, they re-built the engine the next year into a horizontally opposed version using his new wick carburetor design. Carburetors were the method of fuel delivery for most US-made gasoline-fueled engines up until the late 1980s. 1991, Jeep Grand Wagoneer with the AMC360 cu in V8 engine, low-cost commercial vans and 4WDs in Australia continued with carburetors even into the 2000s, the last being the Mitsubishi Express van in 2003. Elsewhere, certain Lada cars used carburetors until 2006, many motorcycles still use carburetors for simplicitys sake, since a carburetor does not require an electrical system to function. EEC legislation required all vehicles sold and produced in countries to have a catalytic converter after December 1992. This legislation had been in the pipeline for some time, with cars becoming available with catalytic converters or fuel injection from around 1990. Fords first fuel-injected car was the Ford Capri RS2600 in 1970, general Motors launched its first fuel-injected car around the same time, when began to introduce fuel-injected engines to its Vauxhall Cavalier/Opel Ascona range
3.
Carbonation
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Carbonation can refer to two chemical processes involving carbon dioxide, The dissolution in a liquid, also known as fizz or effervescence. The process usually involves carbon dioxide under high pressure, when the pressure is reduced, the carbon dioxide is released from the solution as small bubbles, which causes the solution to become effervescent, or fizzy. A common example is the dissolving of carbon dioxide in water, carbon dioxide is weakly soluble in water, therefore it separates into a gas when the pressure is released. Carbonation also describes the incorporation of carbon dioxide into chemical compounds and this occurs in the following cases, In biochemistry Our carbon-based life originates from a carbonation reaction that is most often catalysed by the enzyme RuBisCO. So important is this process that a significant fraction of leaf mass consists of this carbonating enzyme. In reinforced concrete construction Also known as neutralisation, it is a reaction between carbon dioxide in the air and calcium hydroxide and hydrated calcium silicate in the concrete. Carbonation and Acidity Dissolution of Marble in Hydrochloric Acid Demonstration Robert OLeary, ATR Infrared Spectroscopy method for measuring CO2 concentration in Beer. Describes in detail the theory and practice of measuring dissolved CO2 content in soft drinks and beer
4.
Heat treating
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Heat treating is a group of industrial and metalworking processes used to alter the physical, and sometimes chemical, properties of a material. The most common application is metallurgical, Heat treatments are also used in the manufacture of many other materials, such as glass. Heat treatment involves the use of heating or chilling, normally to extreme temperatures, Heat treatment techniques include annealing, case hardening, precipitation strengthening, tempering, normalizing and quenching. Metallic materials consist of a microstructure of small crystals called grains or crystallites, the nature of the grains is one of the most effective factors that can determine the overall mechanical behavior of the metal. Heat treatment provides an efficient way to manipulate the properties of the metal by controlling the rate of diffusion, Heat treating is often used to alter the mechanical properties of a metallic alloy, manipulating properties such as the hardness, strength, toughness, ductility, and elasticity. The crystal structure consists of atoms that are grouped in a specific arrangement. In most elements, this order will rearrange itself, depending on conditions like temperature and pressure and this rearrangement, called allotropy or polymorphism, may occur several times, at many different temperatures for a particular metal. When in the state, the process of diffusion causes the atoms of the dissolved element to spread out. If the alloy is cooled to a state, the atoms of the dissolved constituents may migrate out of the solution. This type of diffusion, called precipitation, leads to nucleation and this forms a microstructure generally consisting of two or more distinct phases. Steel that has been cooled slowly, for instance, forms a structure composed of alternating layers of ferrite and cementite. After heating the steel to the phase and then quenching it in water. This is due to the fact that the steel will change from the phase to the martensite phase after quenching. It should be noted that some pearlite or ferrite may be present if the quench did not rapidly cool off all the steel, unlike iron-based alloys, most heat treatable alloys do not experience a ferrite transformation. In these alloys, the nucleation at the grain-boundaries often reinforces the structure of the crystal matrix, typically a slow process, depending on temperature, this is often referred to as age hardening. Many metals and non-metals exhibit a transformation when cooled quickly. When a metal is cooled quickly, the insoluble atoms may not be able to migrate out of the solution in time. This is called a diffusionless transformation, when the crystal matrix changes to its low temperature arrangement, the atoms of the solute become trapped within the lattice
5.
Iron
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Iron is a chemical element with symbol Fe and atomic number 26. It is a metal in the first transition series and it is by mass the most common element on Earth, forming much of Earths outer and inner core. It is the fourth most common element in the Earths crust, like the other group 8 elements, ruthenium and osmium, iron exists in a wide range of oxidation states, −2 to +6, although +2 and +3 are the most common. Elemental iron occurs in meteoroids and other low oxygen environments, but is reactive to oxygen, fresh iron surfaces appear lustrous silvery-gray, but oxidize in normal air to give hydrated iron oxides, commonly known as rust. Unlike the metals that form passivating oxide layers, iron oxides occupy more volume than the metal and thus flake off, Iron metal has been used since ancient times, although copper alloys, which have lower melting temperatures, were used even earlier in human history. Pure iron is soft, but is unobtainable by smelting because it is significantly hardened and strengthened by impurities, in particular carbon. A certain proportion of carbon steel, which may be up to 1000 times harder than pure iron. Crude iron metal is produced in blast furnaces, where ore is reduced by coke to pig iron, further refinement with oxygen reduces the carbon content to the correct proportion to make steel. Steels and iron alloys formed with metals are by far the most common industrial metals because they have a great range of desirable properties. Iron chemical compounds have many uses, Iron oxide mixed with aluminium powder can be ignited to create a thermite reaction, used in welding and purifying ores. Iron forms binary compounds with the halogens and the chalcogens, among its organometallic compounds is ferrocene, the first sandwich compound discovered. Iron plays an important role in biology, forming complexes with oxygen in hemoglobin and myoglobin. Iron is also the metal at the site of many important redox enzymes dealing with cellular respiration and oxidation and reduction in plants. A human male of average height has about 4 grams of iron in his body and this iron is distributed throughout the body in hemoglobin, tissues, muscles, bone marrow, blood proteins, enzymes, ferritin, hemosiderin, and transport in plasma. The mechanical properties of iron and its alloys can be evaluated using a variety of tests, including the Brinell test, Rockwell test, the data on iron is so consistent that it is often used to calibrate measurements or to compare tests. An increase in the content will cause a significant increase in the hardness. Maximum hardness of 65 Rc is achieved with a 0. 6% carbon content, because of the softness of iron, it is much easier to work with than its heavier congeners ruthenium and osmium. Because of its significance for planetary cores, the properties of iron at high pressures and temperatures have also been studied extensively
6.
Steel
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Steel is an alloy of iron and other elements, primarily carbon, that is widely used in construction and other applications because of its high tensile strength and low cost. Steels base metal is iron, which is able to take on two forms, body centered cubic and face centered cubic, depending on its temperature. It is the interaction of those allotropes with the elements, primarily carbon. In the body-centred cubic arrangement, there is an atom in the centre of each cube. Carbon, other elements, and inclusions within iron act as hardening agents that prevent the movement of dislocations that otherwise occur in the lattices of iron atoms. The carbon in steel alloys may contribute up to 2. 1% of its weight. Steels strength compared to pure iron is possible at the expense of irons ductility. With the invention of the Bessemer process in the mid-19th century and this was followed by Siemens-Martin process and then Gilchrist-Thomas process that refined the quality of steel. With their introductions, mild steel replaced wrought iron, further refinements in the process, such as basic oxygen steelmaking, largely replaced earlier methods by further lowering the cost of production and increasing the quality of the product. Today, steel is one of the most common materials in the world and it is a major component in buildings, infrastructure, tools, ships, automobiles, machines, appliances, and weapons. Modern steel is generally identified by various grades defined by assorted standards organizations, the noun steel originates from the Proto-Germanic adjective stakhlijan, which is related to stakhla. The carbon content of steel is between 0. 002% and 2. 1% by weight for plain iron–carbon alloys and these values vary depending on alloying elements such as manganese, chromium, nickel, iron, tungsten, carbon and so on. Basically, steel is an alloy that does not undergo eutectic reaction. In contrast, cast iron does undergo eutectic reaction, too little carbon content leaves iron quite soft, ductile, and weak. Carbon contents higher than those of steel make an alloy, commonly called pig iron, while iron alloyed with carbon is called carbon steel, alloy steel is steel to which other alloying elements have been intentionally added to modify the characteristics of steel. Common alloying elements include, manganese, nickel, chromium, molybdenum, boron, titanium, vanadium, tungsten, cobalt, and niobium. Additional elements are important in steel, phosphorus, sulfur, silicon, and traces of oxygen, nitrogen, and copper. Alloys with a higher than 2. 1% carbon content, depending on other element content, cast iron is not malleable even when hot, but it can be formed by casting as it has a lower melting point than steel and good castability properties
7.
Carbon
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Carbon is a chemical element with symbol C and atomic number 6. It is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds, three isotopes occur naturally, 12C and 13C being stable, while 14C is a radioactive isotope, decaying with a half-life of about 5,730 years. Carbon is one of the few elements known since antiquity, Carbon is the 15th most abundant element in the Earths crust, and the fourth most abundant element in the universe by mass after hydrogen, helium, and oxygen. It is the second most abundant element in the body by mass after oxygen. The atoms of carbon can bond together in different ways, termed allotropes of carbon, the best known are graphite, diamond, and amorphous carbon. The physical properties of carbon vary widely with the allotropic form, for example, graphite is opaque and black while diamond is highly transparent. Graphite is soft enough to form a streak on paper, while diamond is the hardest naturally occurring material known, graphite is a good electrical conductor while diamond has a low electrical conductivity. Under normal conditions, diamond, carbon nanotubes, and graphene have the highest thermal conductivities of all known materials, all carbon allotropes are solids under normal conditions, with graphite being the most thermodynamically stable form. They are chemically resistant and require high temperature to react even with oxygen, the most common oxidation state of carbon in inorganic compounds is +4, while +2 is found in carbon monoxide and transition metal carbonyl complexes. The largest sources of carbon are limestones, dolomites and carbon dioxide, but significant quantities occur in organic deposits of coal, peat, oil. For this reason, carbon has often referred to as the king of the elements. The allotropes of carbon graphite, one of the softest known substances, and diamond. It bonds readily with other small atoms including other carbon atoms, Carbon is known to form almost ten million different compounds, a large majority of all chemical compounds. Carbon also has the highest sublimation point of all elements, although thermodynamically prone to oxidation, carbon resists oxidation more effectively than elements such as iron and copper that are weaker reducing agents at room temperature. Carbon is the element, with a ground-state electron configuration of 1s22s22p2. Its first four ionisation energies,1086.5,2352.6,4620.5 and 6222.7 kJ/mol, are higher than those of the heavier group 14 elements. Carbons covalent radii are normally taken as 77.2 pm,66.7 pm and 60.3 pm, although these may vary depending on coordination number, in general, covalent radius decreases with lower coordination number and higher bond order. Carbon compounds form the basis of all life on Earth
8.
Charcoal
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Charcoal is a lightweight, black residue, consisting of carbon and any remaining ash, obtained by removing water and other volatile constituents from animal and vegetation substances. Charcoal is usually produced by slow pyrolysis- the heating of wood or other substances in the absence of oxygen, the whole pile is covered with turf or moistened clay. The firing is begun at the bottom of the flue, the success of the operation depends upon the rate of the combustion. The operation is so delicate that it was left to colliers. They often lived alone in small huts in order to tend their wood piles, for example, in the Harz Mountains of Germany, charcoal burners lived in conical huts called Köten which are still much in evidence today. The massive production of charcoal was a cause of deforestation. The increasing scarcity of easily harvested wood was a factor behind the switch to fossil fuel equivalents, mainly coal. Charcoal made at 300 °C is brown, soft and friable, and readily inflames at 380 °C, made at higher temperatures it is hard and brittle, in Finland and Scandinavia, the charcoal was considered the by-product of wood tar production. The best tar came from pine, thus pinewoods were cut down for tar pyrolysis, the residual charcoal was widely used as substitute for metallurgical coke in blast furnaces for smelting. Tar production led to deforestation, it has been estimated all Finnish forests are younger than 300 years. The end of tar production at the end of the 19th century resulted in rapid re-forestation, the charcoal briquette was first invented and patented by Ellsworth B. A. Zwoyer of Pennsylvania in 1897 and was produced by the Zwoyer Fuel Company. The process was popularized by Henry Ford, who used wood. Ford Charcoal went on to become the Kingsford Company, Charcoal has been made by various methods. The traditional method in Britain used a clamp and this is essentially a pile of wooden logs leaning against a chimney. The chimney consists of 4 wooden stakes held up by some rope, the logs are completely covered with soil and straw allowing no air to enter. It must be lit by introducing some burning fuel into the chimney, if the soil covering gets torn by the fire, additional soil is placed on the cracks. Once the burn is complete, the chimney is plugged to prevent air from entering, the true art of this production method is in managing the sufficient generation of heat, and its transfer to wood parts in the process of being carbonised. A strong disadvantage of this method is the huge amount of emissions that are harmful to human health
9.
Quenching
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In materials science, quenching is the rapid cooling of a workpiece to obtain certain material properties. A type of heat treating, quenching prevents undesired low-temperature processes, such as phase transformations, in steel alloyed with metals such as nickel and manganese, the eutectoid temperature becomes much lower, but the kinetic barriers to phase transformation remain the same. This allows quenching to start at a temperature, making the process much easier. High speed steel also has added tungsten, which serves to raise kinetic barriers, even cooling such alloys slowly in air has most of the desired effects of quenching. Extremely rapid cooling can prevent the formation of all crystal structure, if the percentage of carbon is less than 0.4 percent, quenching is not possible. Quench hardening is a process in which steel and cast iron alloys are strengthened and hardened. These metals consist of metals and alloys. This is done by heating the material to a certain temperature and this produces a harder material by either surface hardening or through-hardening varying on the rate at which the material is cooled. The material is often tempered to reduce the brittleness that may increase from the quench hardening process. Items that may be quenched include gears, shafts, and wear blocks, pearlite is not an ideal material for many common applications of steel alloys, as it is quite soft. Steels with this Martensitic structure are used in applications when the workpiece must be highly resistant to deformation. The process of quenching is a progression, beginning with heating the sample, most materials are heated to between 815 and 900 °C, with careful attention paid to keeping temperatures throughout the workpiece uniform. Minimizing uneven heating and overheating is key to imparting desired material properties, the second step in the quenching process is soaking. Workpieces can be soaked in air, a bath, or a vacuum. The recommended time allocation in salt or lead baths is up to 6 minutes, soaking times can range a little higher within a vacuum. As in the step, it is important that the temperature throughout the sample remains as uniform as possible during soaking. Once the workpiece has finished soaking, it moves on to the cooling step, during this step, the part is submerged into some kind of quenching fluid, different quenching fluids can have a significant effect on the final characteristics of a quenched part. Water is one of the most efficient quenching media where maximum hardness is desired, when hardness can be sacrificed, mineral oils are often used
