vi
PENGARUH WAKTU TERHADAP LAJU KOROSI LOGAM Fe DAN Cr PADA BAJA SS 316 DALAM MEDIUM HCl 3M DENGAN
INHIBITOREKSTRAK METANOL DAUN KOPI ( Coffea Robusta L )
ABSTRAK
Pengaruh waktu terhadap laju korosi logam Fe dan Cr pada baja SS 316 dalam medium asam klorida (HCl) 3M telah diteliti dengan menggunakan metode uji pengurangan berat (Weight Loss Test) yaitu dengan perendaman Baja SS 316 dalam variasi waktu 10, 20, dan 30 hari dalam HCl 3M selanjutnya perendaman inhibitor daun kopi (Coffea Robusta L)dengan konsentrasi 6000 ppm selama 24 jam lalu HCl 3M dalam variasi waktu 10, 20 dan 30 hari. Hasil penelitian menunjukkan bahwa laju korosi tertinggididalam HCl 3Mpada logam Fe yaitu perendaman 30 hari sebesar 126,931 mpy serta padalogam Cr yaitu perendaman 30 hari sebesar 47,857 mpyselanjutnya perendaman didalam inhibitor 6000 ppm selama 24 jam lalu HCl 3M diperoleh laju korosi terendah logam Fe sebesar 5,733 mpy pada perendaman 30 haridengan efisiensi inhibitor maksimumyaitu 95,5%sedangkan laju korosi terendah logam Crsebesar 2,447 mpypada perendaman 10 hari dengan efisiensi inhibitor maksimum yaitu 90,62% yang diuji dengan alat Spektrofotometer Serapan Atom. Hasil morfologi permukaan masing – masing baja sebelum dan sesudah terkorosi juga memperlihatkan hasil yang sangat signifikan, dimana dapat dilihat bahwa Baja SS 316sangat mudah terkorosi dalam media HCl 3M.
Kata kunci: Korosi, Laju Korosi Logam, Baja SS 316, Inhibitor
vii
EFFECT TIME OF THECORROSION RATE OF METALS Fe AND Cr ON STEEL SS 316 IN MEDIUM HYDROCHLORIC ACID (HCl)
3M WITHMETHANOL EXTRACT OF LEAVES OF COFFEE INHIBITOR (Coffea Robusta L)
ABSTRACT
Effect time of the corrosion of metals Fe and Cr on steel SS 316 in medium hydrochloric acid (HCl) 3M has been investigated by using the method of weight reduction test, namely soaking Steel SS 316 in the time variation of 10, 20, and 30 days in immersion HCl 3M and inhibitor of coffee leaves (Coffea Robusta L)with concentration of 6000 ppm for 24 hours then HCl 3M in the time variation of 10, 20 and 30 days. The results showed that is the highest corrosion in HCl 3M rate Fe ofin soaking 30 days is 126.931 mpy as well as on the Cr immersion of 30 days isequal to 47.857 mpy further immersion in the inhibitor 6000 ppm for 24 hours and then HCl 3M obtained the corrosion rate of the lowest Fe is 5.733 mpy on the immersion in 30 days with maximum inhibition efficiency is 95.5%, while the corrosion rate of the lowest Cr is 2,447 mpyon immersion in 10 days with a maximum inhibition efficiency is 90.62% by using Atomic Absorption Spectroscopy instrument. Results of surface morphology of each - before and after the corroded steel also showed highly significant results, which can be seen that Steel SS 316 very easily corroded inHCl3M.
Keywords: Corrosion, Corrosion Rate of Metal, Steel SS 316, Inhibitor