EKSTRAK KULIT NANAS SEBAGAI INHIBITOR DALAM MENGHAMBAT LAJU KOROSI PADA BAJA ST 42 DALAM MEDIA NaCl 3,5%

Abstract

This study aims to determine the corrosion rate of ST 42 steel using pineapple peel extract inhibitor in 3.5% NaCl media with variations without inhibitor, 100 ppm, 200 ppm, 300 ppm, 400 ppm, and 500 ppm. Immersion time for 168, 336, and 504 hours. The method used to measure the corrosion rate is weight loss. This research was conducted at the Mechanical Engineering Laboratory, Faculty of Engineering and the Laboratory of Pharmacy Study Program,
Faculty of Mathematics and Natural Sciences, Tadulako University. The results showed that pineapple peel extract could inhibit the corrosion rate on ST 42 steel, at the percentage of immersion 100 ppm, 200 ppm, 300 ppm, 400 ppm, and 500 ppm inhibitor of pineapple peel extract. Especially in the 500 ppm immersion variation with the lowest corrosion rate at an immersion time of 168 hours, which is 0.419 mpy, and has the highest efficiency at an immersion
time of 168 hours, which is 83.378%. Corrosion rate increased with increasing immersion time and decreased with increasing varation of pineapple peel extract inhibitors