Electronic Theses and Dissertation

Korosi adalah proses penurunan kualitas suatu material akibat interaksi dengan lingkungan. Penelitian ini bertujuan untuk menganalisis kemampuan ekstrak daun tapak kuda (Ipomoea pes-caprae L.) dalam menghambat laju korosi pada baja SS 304. Hasil pengujian laju korosi pada penelitian ini menggunakan metode gravimetri. Hasil karakterisasi ekstrak tapak kuda menggunakan Fourier Transform Spectroscopy (FTIR) diperoleh gugus fungsi yaitu O-H terikat, C-H alifatik, C=C, C-H bending dan C-O alifatik yang megindikasikan keberadaan senyawa metabolit sekunder seperti flavonoid, fenolik alkaloid dan tanin. Perhitungan laju korosi dengan satuan yang digunakan yaitu mm/year (standar international). Hasil penelitian menunjukkan konsentrasi maksimum ekstrak daun tapak kuda pada media HCl 1 M sebesar 1200 ppm dengan efisiensi inhibisi 81,11% dan rata-rata laju korosi 0,1275 mm/year. Konsentrasi optimum ekstrak daun tapak kuda pada media NaOH 1 M sebesar 900 ppm dengan efisiensi inhibisi 64,71% dan rata-rata laju korosi 0,0965 mm/year serta pada media NaCl 3,5% selama sebesar 900 ppm dengan efisiensi inhibisi 54,93% dan rata-rata laju korosi 0,2893 mm/year. Morfologi permukaan plat baja SS 304 diamati menggunakan stereo microscope.

Kata kunci : ekstrak daun tapak kuda, inhibitor korosi, Stainless Steel 304

Corrosion is the process of material degradation caused by its interaction with the surrounding environment. This study aimed to analyze the ability of Ipomoea pes-caprae leaf extract as a corrosion inhibitor for SS 304 stainless steel. The corrosion rate was determined using the weight loss method. The characterization of Ipomoea pes-caprae leaf extract using Fourier Transform Infrared Spectroscopy (FTIR) revealed the presence of O–H bonded, aliphatic C–H, C=C, C–H bending, and aliphatic C–O functional groups, indicating the presence of secondary metabolites such as flavonoids, phenolic compounds, alkaloids, and tannins. The corrosion rate was expressed in millimeters per year (mm/year), which is the internationally accepted standard unit. The results showed that the maximum concentration of Ipomoea pes-caprae leaf extract evaluated in 1 M HCl was 1200 ppm, achieving an inhibition efficiency of 81.11% with an average corrosion rate of 0.1275 mm/year. The optimum concentration of the extract in 1 M NaOH was 900 ppm, resulting in an inhibition efficiency of 64.71% and an average corrosion rate of 0.0965 mm/year, while in 3.5% NaCl the optimum concentration was also 900 ppm, yielding an inhibition efficiency of 54.93% and an average corrosion rate of 0.2893 mm/year. The surface morphology of the SS 304 stainless steel specimens was examined using a stereo microscope. Keywords : Ipomoea pes-caprae leaf extract, corrosion inhibitor, 304 stainless steel.