#TITLE_ALTERNATIVE#

• Main Author: PRIMA (NIM : 10509001) ; Pembimbing Dr. Bunbun Bundjali, LETIZIA
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/18833
• Institution: Institut Teknologi Bandung

Corrosion is the destructive attack of metal due to chemical and electrochemical reactions with its environment. Corrosion on the inside of carbon steel pipe distributor in the wet crude oil and natural gas industry really a concern, because of losses incurred due to increased amount of corrosion. The use of corrosion inhibitors is one way to prevent internal corrosion on the inside surface of the steel pipes. Inhibitors should be environmentally friendly, for that reason this study used ethanolamine, formaldehyde, and glycine. Inhibition power, adsorption and thermodynamic parameters of ethanolamine, formaldehyde, and glycine as a corrosion inhibitor of carbon steel in NaCl 1% were tested using the Weight Loss, electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization test (Tafel). Testing is done by varying the concentration from 25 to 150 ppm and temperature variations 25, 45, and 65 °C. Inhibition efficiencies obtained ethanolamine reached 27,96% at 150 ppm and 65 °C. Formaldehyde and glycine inhibition efficiency increases with increasing inhibitor concentration, but the inhibition efficiency decreased with the increase of temperature. formaldehyde inhibition efficiency reached 54,04% at 125 ppm and 25 °C, while glycine reached 25,96% at 150 ppm and a temperature of 25 °C. All the inhibitors tested ethanolamine, formaldehyde, and glycine are cathodic inhibitor, but ethanolamine acts as a mixed inhibitor at 25 °C and formaldehyde acts as an anodic inhibitor at 45 °C. Langmuir adsorption isotherm is used to determine the adsorption mechanism of the inhibitors. Free energy of adsorption in the range of –15,92 to –27,69 kJ/mol and the enthalpy change is negative indicating that the adsorption process of the inhibitor on the surface of carbon steel is an exothermic process, that takes place spontaneously, and meet the physical mechanism of adsorption (physisorption). Entropy change of adsorption formaldehyde and glycine has a negative value, it showes that adsorption process occurs on a system that is arranged, in order or not random, whereas the ethanolamine adsorption process occurs on the surface of carbon steel in disorder system.