Active Thermitic Material
Unexploded Energetic Materials Found in WTC Dust
In November of 2007, Steven E. Jones, having earlier shown the presence of aluminothermic residues in World Trade Center dust samples in the form of solidified iron-rich droplets, announced his discovery of particles of unreacted thermitic materials, in the form of bi-layered chips with gray and red layers. The chips, which are attracted by a magnet, have about the thickness of an eggshell but are much tougher. The red layers have elemental compositions similar to commercial thermite, and to the iron-rich droplets, according to Jones, with spikes for oxygen, iron, aluminum, potassium, and silicon. Jones describes experiments in which the chips burn vigorously when ignited by a torch. 1
One difference between the composition of the red layers and that of simple thermite preparations is the layers' abundance of carbon and silicon. The significance of the carbon would become more clear as Jones and his collegues continued to study the samples and research the state of the art of high-tech aluminothermics in 2001. Carbon and silicon are often major constituents of energetic nano-composites or "super-thermites", forming a matrix that holds the nano-sized iron oxide and aluminum particles in close proximity within a tough, stable material. Additionally, silicon oxides may participate in the thermite reaction as oxidizers of aluminum, and carbon compounds may increase the explosive power of such preparations by generating high gas pressures.
Detailed Analysis of the Chips Provided by 2009 Paper
In April of 2009, the paper Active Thermitic Material Discovered in Dust from the 9/11 World Trade Center Catastrophe documented the detailed analysis of the red-gray chips that had been performed by the authors using analytical instruments such as scanning electron microscopy with X-ray energy-dispersive spectroscopy and differential scanning calorimetry. 2 The paper, summarized in the essay Explosives Found in World Trade Center Dust, includes detailed descriptions of the physical structure of the chips, the chemical compositions of their components, and the chips' thermal behavior.
|Portion of Fig. 4 from Active Thermititic Material Discovered. The corner of a red-gray chip, with the gray and red layers labeled.|
The gray layers are a homogeneous material consisting mostly of iron and oxygen, whereas the red layers are a nano-structured composite material, in which thin plates of mostly elemental aluminum and faceted grains of mostly oxides of iron are embedded in a mesoporous material of mostly silicon and oxygen. The plates and grains, which are highly consistent in shape and size, are only 40nm thick and 100nm in diameter, respectively.
2. Active Thermitic Material Discovered in Dust from the 9/11 World Trade Center Catastrophe, The Open Chemical Physics Journal, 4/3/2009