Expired drugs as inhibitors in electrochemical processes – a mini-review

Abstract

Inhibitors of electrochemical processes have useful applications in corrosion protection of metals and alloys, as well as in galvanotechnics as levellers for the cathodic metal deposition. Active substances of drugs are good inhibitors, taking into account that they have in their molecules structures containing π electrons or lone pair electrons, being able to adsorb on the metal surfaces through weak physical or strong chemical interactions. Significant inhibition efficiency of several drugs have been proved many years ago, but unfortunately, drugs are expensive and their practical applications as corrosion inhibitors for metal and alloys has been delayed. In the present papers, the studies on the inhibition properties in metal corrosion processes of expired drugs have been emphasized, starting with the paper of R. S. Abdel Hameed, published in 2009. There are few studies on the expired drugs used as levellers in the cathodic metal deposition.

Study of the inhibition effect of two novel synthesized amido‐amine‐based cationic surfactants on aluminum corrosion in 0.5 M HCl solution

“…The negative values of obtained are consistent with those obtained from the surface‐active properties and demonstrate for the adsorption process spontaneity of DAMS and DABB surfactants on the aluminum surface. The obtained small values of indicate for the physical adsorption behavior (El‐Etre, Tantawy, et al, 2017; Hamdy & El‐Gendy, 2013; Vaszilcsin et al, 2019).…”

Recent developments in sustainable corrosion inhibitors: design, performance and industrial scale applications

“…Open cost-effective approaches [325]. Because of this, several articles and research papers are published on expired drugs as corrosion inhibitors [326,327]. Various new and expired drugs are tested as effective corrosion inhibitors for different metals and alloys in various electrolytes.…”

A Review on Expired Drug-Based Corrosion Inhibitors: Chemical Composition, Structural Effects, Inhibition Mechanism, Current Challenges, and Future Prospects

“…In the case of the expired Asthalin ( 9), Lupicof (6, 7), Ambroxol (10), Ethambutol (35), and Tobramycin (44) drugs, the highest inhibition efficiency does not occur at relatively low or room temperature, but at 60 °C. Asthalin (9), Ambroxol (10), Ethambutol (35), and Tobramycin (44) almost have similar functional groups which contain amine and hydroxyl groups. The difference lies in the type of heteroatoms and the number of functional groups.…”

“…A review also elaborated on the use of herbal drugs for inhibiting corrosion on alloy steel in corrosive media [18]. Another review reported the electrochemical processes of expired drugs as inhibitors [35]. However, there is no detailed explanation about chemical composition and structure effects on the performance of expired drugs.…”