Commercial activated carbon is a preferred adsorbent for the removal of micropollutants
from the aqueous phase; however, its widespread use is restricted due to high associated
costs. To decrease treatment costs, attempts have been made to find inexpensive alternative
activated carbon (AC) precursors, such as waste materials. Some reviews report the
use of waste materials for the preparation of AC; however, these studies are restricted
to either type of wastes, preparation procedures, or specific aqueous-phase applications.
The present work reviews and evaluates literature dedicated both to the preparation
of AC by recycling different types of waste materials and also to its application
in various aqueous-phase treatments. It is clear that conventional (from agriculture
and wood industry) and non-conventional (from municipal and industrial activities)
wastes can be used to prepare AC, that can be applied in various aqueous treatment
processes, namely to remove organic pollutants, dyes, volatile organic compounds,
and heavy metals. Moreover, high surface areas can be obtained using either physical
or chemical activation; however, combined treatments might enhance the surface properties
of the adsorbent, therefore increasing its adsorption capacity. It is evident from
the revision made that AC prepared from both conventional and non-conventional wastes
might effectively compete with the commercial ones. This happens mostly when the activation
procedures are optimized considering both the raw material used to produce the carbons
and the contaminants to be removed.