Oxidative catalysts for the transformation of phenolic pollutants: a brief review

Phenolics are often produced as wastes by several industrial and agricultural activities. Many of these compounds and their derivatives are extremely dangerous to living organisms, because they are highly toxic and thus represent a serious environmental concern.

Conventional remediation methods of phenol-polluted systems have some disadvantages due to high cost, time-consuming procedures and formation of toxic residues. Conversely, the use of oxidative catalysts, both enzymatic or inorganic, is a promising alternative technology to address the clean up of such wastes. Oxidative enzymes and inorganic compounds, both naturally occurring in soil, behave as biotic and abiotic catalysts and support the transformation of phenolic compounds. The complete mineralization of phenolic pollutants as well as the formation of polymeric products, often less toxic than their precursors, may occur.

The present paper gives a brief review of many aspects concerning the properties of biotic and abiotic catalytic agents effective in the transformation of phenolic compounds. The main mechanisms of the processes as well as their feasibility for catalytic practical applications will be addressed. Examples of their potentiality in the detoxification of phenol-polluted systems will be provided, as well.