"Honeywell and fertilizer maker J.R. Simplot have agreed to build the first commercial facility for Sulf-N 26, a granular fertilizer that is comparable to ammonium nitrate but would be ineffective as a bomb material. Ammonium nitrate combined with fuel oil was used in the bomb that destroyed the Alfred P. Murrah Federal Building in Oklahoma City in 1995."
"Sulf-N 26 is made with a patented Honeywell process that chemically fuses ammonium sulfate, which acts as a fire retardant, and ammonium nitrate. The product is a stable molecule that delivers nitrogen to crops.
The Department of Homeland Security has proposed a rule that would regulate the manufacture and sale of fertilizer containing more than 30% ammonium nitrate because of its misuse as an explosive. Honeywell says it does not expect Sulf-N 26 to be regulated if the proposed DHS rule goes into effect."
Melody Bomgardner reports for Chemical & Engineering News December 12, 2011.