Extraction of a high efficiency and long-acting green corrosion inhibitor from silkworm excrement and its adsorption behavior and inhibition mechanism on copper

A high efficiency and long-acting green corrosion inhibitor (pheophytin) was extracted from silkworm excrement, and its adsorption behavior and inhibition mechanism on copper were investigated in 1 wt% NaCl solution at 30 °C by electrochemical measurements, surface technologies, and theoretical calculations. The results showed that pheophytin had high efficiency and long-acting inhibition performance at a concentration of 0.1 g/L, and the inhibition efficiency reached 93.97% after soaking for 2 h. The adsorption of pheophytin on the copper surface conformed to Langmiur adsorption isotherm, and the adsorption method was physical and chemical mixed adsorption. The pheophytin molecules were spread on the copper surface in a parallel manner so that it covered the largest area to exert an excellent inhibition effect. • A high efficiency and long-acting green inhibitor (pheophytin) was synthesized. • The inhibition performance of pheophytin on the corrosion of copper was studied. • The adsorption mechanism of pheophytin on the copper surface was clarified.