I wanted to stay out of this but
<H1>Thermite

Theories that Aluminothermic Materials Were Used to Destroy the Twin Towers

The idea that thermite or similar preparations were used exclusively or in combination with other methods to destroy the Twin Towers remained unexamined for several years after the attack, despite its merits.
Aluminothermic reactions are exothermic chemical reactions in which aluminum is oxidized while an oxide of another metal is reduced. Although high temperatures are required to initiate such reactions, they are easily self-sustaining once started due to the heat they generate. The most common example of an aluminothermic reaction is thermite, in which powdered aluminum reacts with an iron oxide. Because aluminum has a greater affinity for oxygen than iron, oxygen is transferred from the iron oxide to the aluminum, releasing a great deal of energy and leaving behind molten iron and aluminum oxide.
The spout of orange molten metal and rising white smoke emerging form the South Tower have the appearance of a thermite reaction.
Professor Steven Jones has noted that a number of features evident both before and after the falls of the Towers fit the theory that thermite was used. These include:
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Thermite Variants

Basic thermite preparations can be modified and augmented in various ways to change their properties. The fineness of the aluminum powder determines the speed of the reaction. The use of ultra-fine aluminum powder gives the reaction an explosive quality, resulting in 'super-thermites'. The addition of sulfur in preparations called thermates enhances the ability of the reaction to cut through steel.
Findings reported in Appendix C of FEMA's World Trade Center Building Performance Study seem to fit the thermite theory remarkably well.
Evidence of a severe high temperature corrosion attack on the steel, including oxidation and sulfidation with subsequent intergranular melting, was readily visible in the near-surface microstructure. A liquid eutectic mixture containing primarily iron, oxygen, and sulfur formed during this hot corrosion attack on the steel.
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The severe corrosion and subsequent erosion of Samples 1 and 2 are a very unusual event. No clear explanation for the source of the sulfur has been identified.
Because there are many possible types of pyrotechnics that exploit the energy-dense thermite reaction, the architects of the World Trade Center demolition might have relied entirely on such materials to attack the structures in several different ways, as is suggested by this hypothetical blasting scenario.
http://911research.wtc7.net/wtc/analysis/theories/thermite.html</H1>