Creative Speculation

If the intention of the researchers was to break up the carbon matrix of the red layer to allow analysis of the nanoparticles embedded in it, the result regarding the presence of aluminum does not appear to be compatible with this goal, since it is well-established that MEK might react more or less violently with elemental aluminum. This appears to be a rather important methodological error by the researchers, since such a test might yield inconsistent results depending on whether the temperatures are suitable for the triggering of chemical reactions. The logical conclusion is that one should therefore hypothesize the very opposite of what is claimed in the study, i.e., that there is no elemental aluminum in the compound and that aluminum is present in chemical bonds, or that elemental aluminum is present but in highly oxidized conditions and therefore scarcely reactive.

This is a clear attempt to influence the less than careful reader by suggesting explicitly the analogy between the analyzed samples and the products of thermite reaction, without investigating whether a similar spectrum might be due to other causes and reactions. In other words, the authors jump immediately from the incorrect assessment of the presence of highly reactive elemental aluminum to the (evidently highly desired) conclusion that the collapse of the World Trade Center involved some sort of thermitic reaction of a mysterious product that is triggered at low temperature, provides twice the energy of ordinary thermite, and is characterized by the presence of nanoparticles that give explosive properties to a substance that otherwise is only an incendiary. These are dramatic claims that need to be backed by equally dramatic evidence, not by suggestions. Let's now consider the energy issue.

- Thermal DSC analysis conducted in air -

The authors analyze the behavior of the samples when heated in air in a differential scanning calorimeter (DSC). The result is that all the samples begin to burn in the temperature range between 415 and 435°C. In some cases, the heat generated by the exothermic reaction reaches 7.5 kJ/g. After combustion, spheroidal particles are found in the porous burned residues. Some of these particles are rich in iron and other are rich in silicon (which is transparent and translucent). These particles indicate that high temperatures were reached as a result of an unspecified chemical reaction (which begins at 430°C!). According to the authors, this reaction can only be thermitic. In particular, therefore, the authors claim (page 22 of the paper) that a highly exothermic reaction, such as to generate temperatures of approximately 1400°C, needed to melt iron and iron oxide, was triggered at only 430°C. What this thermitic reaction that is triggered at 430°C might be is not known, since the ignition temperature of commercial thermite is higher than 900°C. The authors seem to have failed to consider that the matrix of the red layer is highly abundant in carbon and that carbon has a lower heating value (or net calorific value) of 34.03 kJ/g, whereas thermite releases 3.9 kJ/g in combustion. In other words, one gram of carbon releases, in combustion at constant pressure, more than eight times the energy released by one gram of thermite. Since the measurement was performed in air (why? Is this another rather embarrassing error in methodology, after the MEK blunder?), one cannot exclude the combustion of carbon, which is instead highly probable. In order to obtain reliable results, since thermite does not require an oxidizer from the external environment, the DSC measurement should have been conducted in an inert gas environment (with nitrogen or argon).

The paper also does not consider the chemical composition of the corrosion-proofing paints and of the vermiculite used as thermal insulation and soundproofing at the World Trade Center and extensively documented by NIST.
These products contain exactly the same elements and exhibit the same structural characteristics as the allegedly thermitic material found by the paper's researchers in their samples.

The researchers therefore appear to have been somewhat hasty in reaching their conclusions.