>>10972835Ammonium nitrate is the fertilizer compound that can be used in explosives, said John Goodpaster, who researches explosives at Indiana at University-Purdue University Indianapolis. This compound is not found in its pure form in the common fertilizers that are commercially available. And, even in its pure form, ammonium nitrate by itself is not explosive.
"The ammonium nitrate is like the engine behind the explosion, but the engine needs fuel," Goodpaster told Life's Little Mysteries. In fact, bombs need two components beside the fertilizer: a detonator and a fuel. The fertilizer must be mixed with a fuel in an exact ratio, and the detonator must be able to generate sufficient energy, he said.
https://www.livescience.com/6413-fertilizer-bombs-work.html 