Ubi ungu adalah salah satu bahan organik yang tersedia di alam yang mempunyai fungsi sebagai anti oksidan. Fungsi dari anti oksidan yang terdapat dalam kandungan ubi ungu ternyata dapat dikembangkan menjadi inhibitor yang menghambat laju korosi baja karbon rendah pada lingkungan air laut. Inhibitor ubi ungu diharapkan dapat menggantikan inhibitor organik sintetis yang tidak ramah lingkungan. Pengembangan inhibitor ubi ungu diharapkan ke depan menjadi inhibitor yang ramah lingkungan, biodegradable, dan murah. Metode pengujian pencelupan atau immersion dilakukan dengan variasi penambahan konsentrasi 2 ml, 4 ml dan 6 ml dan waktu pencelupan selama 5 hari untuk mengetahui kadar optimal penambahan sirup ubi ungu. Hasil penelitian membuktikan bahwa inhibitor ubi ungu mampu menurunkan laju korosi hingga 49.49% dengan penambahan 6 ml.
Purple Potato (Solanum Andigenum) as one of organic materials that exist in nature have function as an antioxidant. The antioxidant function that exist in sweet potato can be developed as inhibitor to reduce corrosion rate of low carbon steel in NaCl 3,5 environment. Purple potato inhibitor is expected to replace the use of synthetic organic inhibitors which is not evironmental friendly. The developing of purple potato inhibitor is expected to become inhibitor that environmental friendly, biodegradable and cheap. The immersion methode is used with the variation of concentration addition 2 ml, 4 ml and 6 ml and 5 days of immersion to determine the optimum concentration addition of purple potato. Result shows that purple potato inhibitor capable to reduce corrosion rate up to 49.49% with 6 ml additon.
