Aplikasi Ekstrak Eceng Gondok dalam Korosi dengan Pelarut Metanol

Abstract

Water hyacinth contains antioxidants such as lignin, tannins, saponins, and alkaloids that can bind to metals to form a protective layer as an organic inhibitor in the corrosion proses. The purpose of this study was to determine the content of antioxidants in water hyacinth extract which can reduce the corrosion rate of metals. The maceration process was carried out with a feed: methanol ratio of 1:9 (w/v). The types of antioxidant compounds were tested using the phytochemical method while the antioxidant activity was tested using the FRAP method. Steel corrosion testing uses the coupon method with a corrosion time of 5 days in air, rainwater, and tap water. The yield of the extract was 72.80%. Based on the results of the phytochemical and FRAP tests, the positive extract contained antioxidant compounds, namely alkaloids, tannins and saponins with an antioxidant concentration of 296.55 ppm. Organic inhibitors that showed the highest inhibition efficiency were at a concentration of 75 ppm with a value of 94.52% in tap water media, 65.53% in air media, and 52.96% in rainwater media.