Comparative Study on Corrosion Inhibition Activity of Nitrogen Compounds Derived from Palm Oil using Two Different Ctalysts Laila Hidayah (a), Ilim (b*), Rifdah Kamilah (c), Kamisah Delilawati Pandiangan (b), and Wasinton Simanjuntak (b)
a) Graduate Student of Department of Chemistry
b) Department of Chemistry
*ilim[at]fmipa.unila.ac.id
c) Student of Department of Chemistry Faculty of Mathematics and Natural Sciences, the University of Lampung, Jl. S. Brojonegoro No 1 Bandarlampung, 35145 Indonesia
Abstract
This research was carried out to obtain palm oil-derived nitrogen compounds through two step reaction procedure and application of the resulting compounds corrosion inhibitors for mild steel in a 3% NaCl solution saturated with CO2. The first step of the reaction was the conversion of palm oil into methyl esters through transesterification reaction using a zeolite-A catalyst. The second step was the conversion of methyl ester into nitrogen compounds by reacting the methyl esters with diethanolamine using two different catalysts, namely zeolite-A and sodium methoxide (NaOCH3), and carried out in a hydrothermal autoclave reactor at a temperature of 80 C with a reaction time of 48 hours. The use of zeolite-A and autoclave is a novelty of this research in the production of nitrogen compounds from vegetable oils, since this method has not been reported in previous research. The experimental results showed that the fatty acids in palm oil were completely converted into methyl esters as proven by GC-MS analysis. GC-MS analysis also showed the formation of nitrogen compounds with a relative percentage of 17.96% in the reaction product using the zeolite-A as a catalyst, and 4.18% in the product obtained using the NaOCH3 as a catalyst. Corrosion experiments using the Wheel test method showed that the use of 150 ppm of the products was able to provide an inhibition efficiency of 84.15% by the product produced with the use of zeolite-A, and 63.60% by products with the use of NaOCH3. The activity of the resulting compounds as corrosion inhibitor was also supported by SEM results which show that the sample surface is well protected.
