Study On Inhibition Effect Of Domperidone On Copper In Two Chloridion Contained Solutions

Copper is widely used in the fields of industry and daily life because of itsexcellent properties. However, it will be corroded and damaged remarkably in the harshcondition, such as the solution containing Cl-ion. There are many research reportsaddressing copper inhibitors, most of them are benzotriazole compounds which aredangerous to the environment and lack of economical applicability. In order toovercome these problems, current research efforts have been concentrated on theexploration of new green corrosion inhibitors.In this paper, domperidone was investigated in3.5wt.%NaCl solution and1MHCl solution by weight loss and electrochemistry tests. The surface morphology wascharacterized, and the inhibition mechanism was also discussed.1. Study on corrosion inhibition of copper by domperidone in3.5wt.%NaCl solutionDomperidone as the corrosion inhibitor was investigated in3.5wt.%NaCl solutionby weight loss and electrochemistry tests. The inhibition efficiency of domperidone oncopper achieved the highest value of94.2%with20mg L-1domperidone according tothe results of potentiodynamic polarization and electrochemical impedance spectroscopy,which shows that domperidonehas has good protective ability for copper corrosion. Theobserved largest Ecorrshift was about117mV, which confirms that domperidone acts asan anodic inhibitor for copper in3.5wt.%NaCl solution. Surface observation wasperformed to further confirm the inhibition action of domperidone using scanningelectron microscope (SEM) and atomic force microscope (AFM). The molecularsimulation of domperidone on copper was calculated by quantum chemistry method,which provided the adsorption model of domperidone molecule on the Cu (001) surface.It was found that the adsorption of domperidone on copper surface in3.5wt.%NaClsolution obeys the Langmuir adsorption and its inhibition efficiency decreases with thetemperature increasing.2. Study on corrosion inhibition of copper by domperidone in1M HCl solutionDomperidone as the corrosion inhibitor was investigated in1M HCl solution byweight loss and electrochemistry tests, too. The inhibition efficiency of domperidone oncopper got the biggest value of79.15%with20mg L-1domperidone according to theresults of the potentiodynamic polarization curves and weight loss. The values of Ecorrremain almost unchanged with domperidone addition, indicating domperidone as a mixed-type inhibitor. The inhibition efficiency decreased with increasing thetemperature, and adsorption of domperidone on copper surface in1M HCl solution wasfound to follow the Langmuir adsorption.