Search

The purpose of this research are to synthesis methyl ester from used cooking oil refined with zeolite and activated pumice and to investigate its potential as biodiesel. The research stages were activating the natural zeolite and pumice with temperature variations of 500 and 600 °C, refining waste cooking oil with various concentrations, trans-esterification of refined waste cooking oil, characterization and identification of methyl esters by using Gas Chromatography-Mass Spectrometry (GC-MS). The best refining was resulted from free fatty acids and clarity at a concentration of 30% natural zeolite with a yield of 67.17%. The trans-esterified methyl esters have a density of 0.881 g/mL, refractive index of 1.447, viscosity of 4.92 cSt, acid number of 0.49 mg-KOH/g, and saponification number of 198.8 mg-KOH/g, which have high potential as biodiesel. The main components of trans esterified methyl ester from refined waste cooking oil are methyl palmitate, methyl oleate, and methyl stearate with the compositions of 46.27, 40.26, and 5.19%, respectively. [ABSTRACT FROM AUTHOR]

The heterogeneous catalysts in biodiesel synthesis is more environmentally friendly and reusable. Alkaline earth oxides are less alkaline than alkaline oxides. Biodiesel is an alternative fuel, which has been started to be developed as a renewable energy. The aim of this study was to synthesize biodiesel from low-quality crude palm oil (CPO) with heterogeneous catalyst of MgO-K2O using ultrasonic waves. The stages in this study were (a) activation of natural zeolites, (b) refining of low quality of CPO, (c) synthesis of MgO-K2O catalyst at ratio of 10 : 1, 10 : 2, 10 : 3 (MgO : KOH) and (d) transesterification of esterified CPO (variations in the amount of catalyst 10%, 15%, and 20%). This research achieved the optimum conditions for methyl ester synthesis at ratio of 10 : 2 (MgO : KOH) of catalyst composition (15% w/w of oil), and the yield was 88.086%. The character of the methyl ester was in accordance of Indonesian biodiesel standard, therefore, the methyl ester obtained has the potential as biodiesel. The composition of the synthesized methyl ester were 1.96% methyl myristate, 40.42% methyl palmitate, 44.32% methyl oleate, and 7.46% methyl stearate. [ABSTRACT FROM AUTHOR]

Indonesian government has committed to increase exploration of wasters potential. Microalgae is an excellent water organism which high potential converted to biodiesel. Moreover, microalgae have a better photosynthetic ability than ordinary plants. Thus, microalgae can take part in preventing global warming by reducing carbon dioxide levels in the atmosphere. Recent research has successfully isolated several microalgae isolates from water area in East Java. However, they had not been characterized yet. Therefore, the aim of this research was to characterize two of those isolates in terms of potential as a feedstock of biodiesel production. The results showed that based on phenotype analysis, it could be concluded that Kelp I and Kelp IV were Prochloron sp. and Chlamydomonas sp. Prochloron sp. grew up optimally within 16-18 days, while Chlamydomonas sp. had an optimum growth at 13-18 days. The lipid yield of dried microalgae is 31.85% and 46.86% for Prochloron sp. and Chlamydomonas sp., respectively. Fatty acids composition in both Prochloron sp. and Chlamydomonas sp. were dominated by palmitic acid, which is very good for biodiesel synthesis. [ABSTRACT FROM AUTHOR]