It started with pigs. And with the smell there.
- A pig farm near Deutschlandsberg in Styria. The pungent ammonium odor was the problem—and Tihomir Lelas had responded to a tender.
The Croatian was working at the time as the head of a research institute in Vienna. He knew about zeolite—the ancient volcanic rock that had long been known as a filter and absorber. The experiment in Styria was a resounding success. The pulverized stone not only freed the barn of ammonia. "The pigs were licking the stuff like crazy," Lelas later recounted. Fewer animals died in the barn. The diarrhea disappeared. The cannibalism decreased.
And he began to research.
First, a look back—what ball mills are and why they have a problem
To understand what tribomechanical activation is, one must first understand what it is not. Let's just start from here.
Conventional grinding processes are carried out using ball mills. A ball mill is basically a rotating drum filled with giant balls or discs made of metal—sometimes steel, sometimes other hard alloys. The minerals are placed in the drum. The drum rotates. The balls roll over each other and over the mineral. The mineral is crushed, squeezed, ground—finer and finer, smaller and smaller.
For coarse applications, this works well enough. But for fine grain sizes below 50 micrometers, the problems begin.
Problem 1: Metal abrasion. The balls wear down. With every collision with the hard mineral, tiny metal particles rub off the balls. This metal abrasion ends up in the ground product. Zeolite attracts metal—that is actually its strength, its adsorption capacity. But this also means: it absorbs the metal abrasion from the balls. A finely ground zeolite from a ball mill can be contaminated with heavy metals—not because the raw material was, but because the grinding process caused it. A simple magnet test shows this: dissolve zeolite in a glass of water, stir it, hold a magnet to the outside of the glass—and watch what happens. With ball-mill zeolite, a dark cloud is pulled toward the magnet. That is the metal abrasion.
Problem 2: Destruction of the crystal lattice. This is the actual core problem. Zeolite has a unique inner structure—a crystal lattice with tiny voids and channels, which is responsible for its adsorption and ion exchange capacity. When zeolite is ground in a ball mill, these crystal lattices are squeezed and damaged. The balls press on the particles from the outside—the crystal lattice inside cannot withstand the pressure and collapses.
A zeolite with a destroyed crystal lattice is a zeolite that can no longer do what zeolite is known for. It is still chemically zeolite. But it no longer works like zeolite.
That is the reason why some claim zeolite does not work. They are right—the incorrectly ground zeolite actually does not work. And does not do what zeolite is capable of.
