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Pyrolysis is a thermochemical decomposition of organic material at elevated temperatures without the participation of oxygen. It involves the simultaneous change of chemical composition and physical phase, and is irreversible. The word is coined from the Greek-derived elements pyro "fire" and lysis"separating".
Pyrolysis is a case of thermolysis, and is most commonly used for organic materials, being, therefore, one of the processes involved in charring. The pyrolysis of wood, which starts at 200-300 °C (390-570 °F),[1] occurs for example in fires where solid fuels are burning or when vegetation comes into contact with lava in volcanic eruptions. In general, pyrolysis of organic substances produces gas and liquid products and leaves a solid residue richer in carbon content, char. Extreme pyrolysis, which leaves mostly carbon as the residue, is called carbonization.
The process is used heavily in the chemical industry, for example, to produce charcoal, activated carbon, methanol, and other chemicals from wood, to convert ethylene dichloride into vinyl chloride to make PVC, to produce coke from coal, to convert biomass into syngas and biochar, to turn waste into safely disposable substances, and for transforming medium-weighthydrocarbons from oil into lighter ones like gasoline. These specialized uses of pyrolysis may be called various names, such as dry distillation, destructive distillation, or cracking.
Pyrolysis also plays an important role in several cooking procedures, such as baking, frying, grilling, and caramelizing. In addition, it is a tool of chemical analysis, for example, in mass spectrometry and in carbon-14 dating. Indeed, many important chemical substances, such as phosphorus and sulfuric acid, were first obtained by this process. Pyrolysis has been assumed to take place during catagenesis, the conversion of buried organic matter to fossil fuels. It is also the basis of pyrography. In their embalming process, the ancient Egyptians used a mixture of substances, including methanol, which they obtained from the pyrolysis of wood.
Pyrolysis differs from other high-temperature processes like combustion and hydrolysis in that it usually does not involve reactions with oxygen, water, or any other reagents. In practice, it is not possible to achieve a completely oxygen-free atmosphere. Because some oxygen is present in any pyrolysis system, a small amount of oxidation occurs.
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What is reformed gas?
A lower-thermal-value fuel gas made by pyrolysis and steam decomposition of high-thermal-value natural and refinery gas
How does limestone remove sulphur dioxide?
The lime (CaO) reacts with SO2: 2CaO (s) + 2SO2 (g) + O2(g) .........> 2 CaSO4 (s) So the sulphur dioxide is removed and deposited as calcium sulphate.
Is smoke a liquid in a gas or solid in a liquid or gas in a solid or solid in a gas?
AnswerIt is a solid it just looks like a gas but its not AnswerSmoke is the collection of airborne solid and liquid particulates and gases emitted when a material undergoes combustion or pyrolysis, together with the quantity of air that is entrained or otherwise mixed into the mass. For the source and more detailed information concerning your request, click on the related links section (Wikipedia) indicated below.
Is carbon found in fossil fuel?
Carbon monoxide is not a fossile fuel. CO can result from incomplete combustion of a fossil fuel. Incomplete combustion will only occur when there isn't enough oxygen to allow the fuel to react completely to produce carbon dioxide and water. It also happens when the combustion is quenched by a heat sink such as a solid surface or flame trap. For most fuels, such as diesel oil, coal or wood, pyrolysis occurs before combustion. In incomplete combustion, products of pyrolysis remain unburnt and contaminate the smoke with noxious particulate matter and gases. Partially oxidized compounds are also a concern; partial oxidation of ethanol can produce harmful acetaldehyde, and carbon can produce toxic carbon monoxide. The quality of combustion can be improved by design of combustion devices, such as burners and internal combustion engines. Further improvements are achievable by catalytic after-burning devices (such as catalytic converters) or by the simple partial return of the exhaust gases into the combustion process. Such devices are required by environmental legislation for cars in most countries, and may be necessary in large combustion devices, such as thermal power plants, to reach legalemission standards. The degree of combustion can be measured and analyzed, with test equipment. HVAC contractors, firemen and engineers use combustion analyzers to test the efficiency of a burner during the combustion process. In addition, the efficiency of an internal combustion engine can be measured in this way, and some states and local municipalities are using combustion analysis to define and rate the efficiency of vehicles on the road today.
How does Methanol work?
I am not aware of any direct way of producing methanol from methane. The only two ways I know that you can make methanol is by reacting carbon monoxide with hydrogen or by the pyrolysis of wood. Almost all the methanol made today is produced by the Syngas method. In it, methane is converted to carbon monoxide and hydrogen, which are then formed into methanol. Researchers are working on a catalyst to directly convert methane to methanol, which is done by inserting one oxygen atom into a methane molecule, between the carbon atom and a hydrogen atom. Their biggest problem right now is the most efficient catalysts work at temperatures high enough to ignite methanol.
Does wood undergo pyrolysis before it burns?
Wood undergoes pyrolysis as it burns. Pyrolysis is the destructive distillation of the wood, producing gasses, which burn as they leave the wood, and carbon, which will also eventually burn. This is how wood normally burns.There is a link to an article on pyrolysis below.
What are disadvantages of pyrolysis?
technology is still evolving. markets are yet to be developed for char product and pyrolysis liquids.
What has the author S K Chakrabartty written?
S. K. Chakrabartty has written: 'Modern coal pyrolysis' -- subject(s): Coal, Pyrolysis
What has the author Rodney Winston May written?
Rodney Winston May has written: 'Pyrolysis--gas chromatography' -- subject(s): Gas chromatography, Pyrolysis
What is the cause of pyrolysis?
Pyrolysis is a chemical decomposition caused by heat. When a combustible material is exposed to high temperatures for a long time will dry out, break and can even burn.
What does the decomposition of organic matter by heat describe?
Pyrolysis
What is the flash point of tire pyrolysis oil?
55c
What has the author R M Felder written?
R. M Felder has written: 'Analysis of volatile products from the slow pyrolysis of coal' -- subject(s): Coal, Testing, Pyrolysis
What do carbon pyrolysis wood charbon briquettes have in common?
charcoal
How are tires recycled?
Tyres can be recycled by low-temperature pyrolysis.
Which tool did newton use to prove his theories about colors?
pyrolysis
What is pygas?
Pygas means pyrolysis gasoline, which is having aromatic rich.
