Explain the physical chemistry of alumino-thermic process.
Answers
Answer:
Aluminothermic reactions are exothermic chemical reactions using aluminium as the reducing agent at high temperature. The process is industrially useful for production of alloys of iron.[1] The most prominent example is the thermite reaction between iron oxides and aluminium to produce iron itself:
Fe2O3 + 2 Al → 2 Fe + Al2O3
This specific reaction is however not relevant to the most important application of aluminothermic reactions, the production of ferroalloys. For the production of iron, a cheaper reducing agent, coke, is used instead via the carbothermic reaction.The aluminothermic reaction is used for the production of several ferroalloys, for example ferroniobium from niobium pentoxide and ferrovanadium from iron, vanadium(V) oxide, and aluminium.[1][2] The process begins with the reduction of the oxide by the aluminium:
3 V2O5 + 10 Al → 5 Al2O3 + 6 V
Other metals can be produced from their oxides in the same way.[3][4][5]
Explanation:
Aluminothermic reactions have been used to welding rail tracks on-site, useful for complex installations or local repairs that cannot be done using continuously welded rail. Another common use is the welding of copper cables (wire) for use in direct burial (grounding/earthing) applications. It is still the only type of electrical connection recognized by the IEEE (IEEE, Std 80-2001) as continuous un-spliced cable.
Answer:
In Alumino thermite process the aluminium act as reducing agent. In this preocess the oxides of various metals (like chromium, iron, etc.) are converted into their corresponding metals. For example: the reduction of ferrous oxide in presence of aluminium results in the formation of ferrous metal.