Environment concerns extend to explosives

A research team in Munich is attempting to produce "green" explosives that retain their destructive force but which don't pollute the environment. The project is the ultimate proof that environmental concerns are reaching into every aspect of life.

The incongruity of developing environmentally-friendly rockets and grenades was not lost on Prof Thomas Klapotke of the University of Munich, but there were sound reasons behind the research, he said.

Armies use a vast quantity of explosives and live rounds during training sessions. These deposit large amounts of pollutants in the environment and also expose troops to toxic substances.

He is developing a new generation of nitrogen-based explosives which eliminate much of this. The goal, he said, was to produce explosives that retained their destructive potential but which, when discharged, released pure nitrogen gas and oxygen, in effect "hot air".

The work had potential outside the military, Prof Klapotke said. Propellants used in rockets were similar to those in launch vehicles used to put satellites into orbit. His work could lead to less polluting alternatives.

He has already developed two nitrogen-based explosive formulas that are more powerful than the explosives they would replace. "They are at least as good as if not better than existing explosives," he said, adding, "the problem at the moment is price".

About 80 per cent of the air we breath is nitrogen so it is a cheap and plentiful resource. It takes considerable processing energy to convert this into green explosives, however, so these new materials cost more. Trinitrotoluene, TNT, was a commonly used high explosive but it was highly polluting, Prof Klapotke said.

"It persists for a very long time" and tends to bioaccumulate in the food chain. He has developed a less pollutant alternative that is biodegradable and less toxic.