Charcoal ignition temperature

Perchloryl fluoride does not attack glass at moderate temperature, but decomposes at 25°C on contact with activated Si02 or AI2O3, particularly in the presence of small amounts of H2O. With other surface-active materials, such as charcoal, ignition may take place. However, there is no reaction at room temperature with synthetic zeolites. It passes freely through a 4 A molecular sieve, but is completely absorbed... 

Other work has shown that high volatile content charcoals lower the activation energy and reduce the ignition temperature of the black powder, while removal of volatile matter from the charcoal increases both activation energy and ignition temperature. 

Violette found that the temperature of carbonization of wood is directly related to the ignition temperature of the charcoal obtained (Table 76). 

The relation between the ignition temperature of charcoal and the carbonization temperature of WOOD... 

NOTE 2 The criteria are based on the self-ignition temperature of charcoal, which is 50°C for a sample cube of 27 rrf. Substances and mixtures with a temperature of spontaneous combustion higher than 50°C for a volume of 27 m should not be assigned to this hazard class. Substances and mixtures with a spontaneous ignition temperature higher than 50°C for a volume of 450 litres should not be assigned to hazard Category 1 of this hazard class. 

Sulphur ignites at 223 C in the air. This relatively low ignition temperature is often used for firework compositions for ease of ignition. Sulphur is used as a raw material for black powder in combination with potassium nitrate and charcoal and it is also used for white smoke compositions. 

PROPANONE (67-64-1) CH3COCH3 Extremely flammable low ignition temperature makes it very dangerous. Forms explosive mixture with air [explosion limits in air (vol %) 2.6 to 12.8 flash point -2°F/-19°C autoignition temp 869°F/465°C Fire Rating 3]. Reacts violently with mixtures of concentrated sulfuric and nitric acid chloroform. Reacts, possibly violently, with activated charcoal, aliphatic amines, bromine, bromine trifluoride, bromoform, chlorotriazine, chromic(IV) acid, chromic(VI) acid. 

Potassium nitrate reacts with charcoal to produce potassium carbonate, potassium oxides, and potassium cyanide. More cyanide is formed at high temperature and pressure or in the presence of iron or its compounds. Potassium oxides are formed whenever potassium carbonate is held molten at atmospheric pressure. The rate of reaction is low, and the reaction is an equilibrium reaction which is easily reversed. At atmospheric pressure the molten material produced is predominantly potassium carbonate. The temperature achieved are sufficient to ignite aluminum. Flitter stars can be made with potassium nitrate and aluminum but charcoal is often added to lower the ignition temperature and render the stars more easily ignited. Similarly sulfur, antimony sulfide, or arsenic sulfide is used to start and control the burning of aluminum in flitter stars. Microscopic and microchemical examination of the sparks of such stars show a thin film of potassium oxides and potassium aluminates with some traces of liquid potassium oxide and potassium sulfide films over the mass of molten unreacted aluminum. 

The ignition points of charcoal and other carbons vary widely and are influenced by the presence of catalysts such as lead salts. Nebel and Cramer, in a study concerning the behavior of carbon in gasoline engines, reported an ignition temperature of 555°C for pure carbon, but the addition of lead compounds depressed the ignition... 

The pelleted explosive ( ammonpulver , containing 10% charcoal) normally ignites at 160-165°C, but presence of rust, or copper oxide or zinc oxide lowers the temperature to 80-120°C. 

Calcium sulfate exhibits high thermal stability. At elevated temperatures, it occurs in anhydrous form. The dihydrate loses its water molecules upon strong heating. When ignited with charcoal, it is reduced to calcium sulfide ... 

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