+212 522 25 12 15 / 64
+212 522 25 35 90


Rue Ach Charif Al Idrissi
BP 5118, Maarif - 20370 - Casablanca - Maroc

Bleaching earths

Terres décolorantes | Bleaching earths

The bleaching earth is a powder of mineral origin generally composed of bentonite, attapulgite and/or sepiolite.

It acts as an adsorbent whose adsorption capacity depends on the structure and mineralogical properties such as: internal surface, granulometric distribution and total porosity.

The forms of the bleaching earth:

Bleaching earth comes in two forms:

  • Natural bleaching earth : treated only by physical way, it adsorbs in its natural state.
  • Activated bleaching earth : physically treated then chemically with an acid treatment to increase its porosity and its adsorption capacity.

The applications of bleaching earth:

It is used globally alone or with the addition of natural silica to remove impurities during the refining process of vegetable or animal oils. The bleaching earth removes colors, under-oxidation products and traces of metals, while silica removes soap, phospholipids and also metals.

Attapulgite type bleaching earths are also used in the removal of polar compounds present in aircraft fuels.