Charcoal made from roasting wood differs from activated carbon in that its surface is contaminated by other products, but further heating will drive off these compounds to produce a surface with high adsorptive capacity. Although the carbon atoms and linked carbons are most important for adsorption, the mineral structure contributes to shape and to mechanical strength. Spent activated carbon is regenerated by roasting, but the thermal expansion and contraction eventually disintegrate the structure so some carbon is lost or oxidized. Temperature effects on adsorption are profound, and measurements are usually at a constant temperature. Graphs of the data are called isotherms .
Most steps using adsorbents have little variation in temperature.
Translation of some of the above to Portuguese.