Abstract. Research has been carried out on the effect of the concentration of Kepok banana peel extract as an inhibitor on API 5L carbon steel in 3% NaCl corrosive medium. API 5L carbon steel immersion was carried out for 7 hours with two variations of immersion temperature, namely 40 and 80 oC and five variations in the concentration of corrosion inhibitors, namely 0%, 2%, 4%, 6%, 8%. Corrosion rate testing was carried out using the weight loss method. The results showed that the largest corrosion rates at immersion temperatures of 40 and 80 oC were at 0% inhibitor concentrations, namely 60.91 mm / y and 86.91 mm / y. Meanwhile, the lowest corrosion rate was at the inhibitor concentration of 8% at immersion temperatures of 40 and 80 oC, namely 32.51 mm / y and 63.92 mm / y. The greatest effectiveness of corrosion inhibitors occurred at a concentration of 8% at immersion temperatures of 40 and 80 oC of 56.63%, and 26.44%. The results of the X-Ray Diffraction (XRD) characterization showed that the phase formed was pure Fe. Scanning Electron Microscopy (SEM) characterization showed uneven clusters and smaller size, holes and cracks were also less in 8% inhibitor at immersion temperature of 40 and 80 oC compared to inhibitor 0% at immersion temperature 40 and 80 oC.

Nanotitania has been prepared by sol gel method using ethanolamine as surfactant. This research was conducted to determine the effect of ethanolamine on the phase formation, particle size and surface area of TiO2. In this study Ti-butoxide was used as a precursor and ethanol as a solvent, and then HCl. The amount of ethanolamine was varied to 0; 0.5; 1; 1.5; and 2 ml. The samples were calcined at a temperature of 500ºC for 4 hours. TiO2 was characterized using X-Ray Diffraction (XRD), Transmission Electron Microscopy (TEM), and Surface Area Analyzer (SAA) with BET method. The results of XRD characterization showed that in samples A-0.0 and A-0.5 an anatase phase was formed, whereas in the sample A-1,0 and A-1,5 an anatase, brookite, and rutile phases were formed with a weight percentage of 57,65 ± 1,6% wt; 27,06 ± 1,8% wt, and 15,29 ± 0,4% wt. Meanwhile, for sample A-1,5 it is 69,96 ± 1.6% wt, 24,52 ± 1,5% wt, and 5,52 ± 0,3% wt. Sample A-2.0 only produced anatase and brookite phases with weight percentages of 78,53 ± 1.5% wt and 21,47 ± 1.5% wt. The results of TEM characterization using ImageJ software show that the TiO2 particle size in sample A-1,0 was 15,8 ± 1,0 nm. The results of the analysis surface area of sample A-1, produced the largest specific surface area, that is 172 m2/g, the smallest specific surface area was produced in sample A-1,5 that is 72,07 m2/g.