Nontoxic Corrosion Inhibitors for Aqueous Medium : A Review

In the past two decades, the research in the field of ‘‘green’’ corrosion inhibitors has been directed toward the goal of using cheap, effective molecules of low or ‘‘zero’’ negative environmental impact. Therefore, the use of non–toxic inhibitors has also become one of the major selection requirements. There is still an increased attention directed towards the development of environmentally compatible, nonpolluting corrosion inhibitors. In this review, non-toxic corrosion inhibitors are classified in two main groups: inorganic and organic. Molybdate, silicate, tangstenate, phosphate, borate and lanthanide group salts as inorganic inhibitors and natural materials (extract of plants leaf, flower, seed …) drugs, some polymers, bio-materials and few other materials are studied as organic inhibitors. Inhibition mechanisms of these materials are discussed widely.