The Isolation and Characterization of Protein from Tofu Waste as Corrosion Inhibitor towards Carbon Steel in 1% NaCl Solution

• Main Author: ZUNITA (NIM 10505029), MEGAWATI
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/12370
• Institution: Institut Teknologi Bandung

Corrosion could damage many aspects in life; therefore corrosion inhibitor was needed to overcome those problems. The aim of this research is to isolate protein from the foodstuffs waste that contain high protein, such as tofu, and at the same time is to increase the economical value of tofu waste. The isolation was carried out by two methods: precipitation by 10% v/v acetic acid solution and protein fractination by ammonium sulphate. The determination of corrosion inhibition activity utilized the Tafel method at the concentration of 80 ppm in 1% w/v NaCl solution. The corrosion inhibition activity of protein isolated by precipitation methods is 53.41%. Six protein fractions (fraction of 0%-60%) was obtained from fractination methods. The largest corrosion inhibition activity (70.89%) was shown on the fraction of 20-30%, which is larger than the corrosion inhibition activity of the tofu waste before being isolated (29.74%). Amino acids contained in isolated protein that have the influence to corrosion inhibition activity was analyzed by hydrolysis methods, which are: methionine, proline, tyrosine, asparagine, and thrytophane. The results of this research showed that protein isolated from the tofu waste have the potent as corrosion inhibitor towards carbon steel in 1%NaCl solution.