Aryswan, Adhe2013-01-172013-01-172013-01-17Sahlanhttp://repository.unri.ac.id:80/handle/123456789/1512EKSTRAK KULIT BUAH MANGGIS (Garcinia mangostana) SEBAGAI INHIBITOR KOROSI BAJA LUNAKINHIBITOR KOROSI BAJA LUNAK DALAM MEDIA ASAM KLORIDA Adhe Aryswan1, R. Usman Rery, Maria Erna Program Studi Pendidikan Kimia Fakultas Keguruan dan Ilmu Pendidikan Universitas Riau ABSTRACT Mangosteen rind extract has been used as an inhibitor of mild steel corrosion in HCl medium. The determination of the corrosion inhibition efficiency was calculated by using weight loss method. The optimum conditions were determined by the variation of corrosive media concentration, the variation of contact time and the variations of extract concentration. The result showed that the efficiency of optimum corrosion inhibition was 59,07%, with the condition of 0.5 M HCl medium concentration, 5-days contact time in the extract concentration of 200 ppm. The inhibition of mangosteen rind extract occurred spontaneously through chemisorption on metal surfaces. It was shown from the Gads of major component in mangosteen rind, namely -mangostin for -47,0526 kJ mol-1otherMangosteen, Garcinia mangostanaCorrosion InhibitorMild Steel.student Paper Post Degree