Polyethylene glycol and its derivatives as environmental sustainable corrosion inhibitors: A literature survey

Increasing ecological awareness is escalating pressure on the synthesis, development, and use of nonhazardous alternatives to traditional toxic corrosion inhibitors. Polyethylene glycol (PEG) and PEG derivatives represent a new class of environmental sustainable alternatives. They have several beneficial properties, such as being nonvolatile and having a relatively higher vapor density. PEG and its derivatives also possess biodegradability and low flammability that offer them as environmentally sustainable alternatives for use in different industrial and biological applications, including as corrosion inhibitors. PEG and its derivatives are relatively highly stable in acids and bases, and therefore they can be used as corrosion inhibitors at various pH ranges of electrolytes without degradation. They can also be used as high-temperature corrosion inhibitors as they are thermally stable. PEG and most of the PEG derivatives are highly stable for oxidation by H2O2 and hydride reduction (NaBH4). One of the greatest advantages of using PEG and its derivatives as corrosion inhibitors is that they can be recovered from aqueous media through an extraction process using a suitable solvent or by the direct distillation method. A literature study shows that several reports are available on PEG and its derivatives as green corrosion inhibitors. This chapter features the collection of some major reports on PEG and PEG derivatives as corrosion inhibitors.