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Biodiesel Production from Crude Palm Oil Using Kapok Skin KOH (Ceiba Pentandra) Catalyst as Solid Green Catalyst

Jalaluddin, Ginting Zainuddin, Maliki Syariful, Setiawan Arif, Zulfa

Journal of Ecological Engineering

2022

Vol. 23, nr 5

286--292

Biodiesel is one type of renewable alternative energy that has great potential to be developed. Biodiesel is a fuel consisting of a mixture of mono-alkyl esters of long-chain fatty acids made from renewable sources, such as vegetable oils or animal fats, one of which is crude palm oil (CPO). Crude palm oil contains free fatty acids in high levels, so treatment is needed to reduce free fatty acids by a reaction known as the esterification reaction. Then, the transesterification process is carried out to produce biodiesel (methyl ester). The purpose of this study was to analyze the effect of catalyst mass, a mole ratio of CPO to moles of methanol and the effect of adding THF co-solvent to biodiesel purity. The catalyst used is a heterogeneous catalyst from kapok fruit peel waste. Kapok fruit rind was calcined at 700°C for 8 hours. The independent variable varied the mole ratio of oil to methanol in a 1:4 ratio; 1:6; 1:8; and 1:10 with a catalyst weight variation of 3 and 4%. Meanwhile, for the addition of co-solvent, variations of THF: methanol v/v 1:1 and 2:1, were carried out. The biodiesel properties such as density, viscosity, water content and acid number, were evaluated and compared with the Indonesian National Standard. The results showed that the transesterification reaction with the addition of co-solvent resulted in a higher methyl ester content than that without the addition of co-solvent. The highest yield of methyl ester without the addition of co-solvent was 79.16%, while the yield of the methyl ester with the addition of THF co-solvent with a ratio of 1:1 and 2:1 v/v to methanol was 90.09 and 94.09%, respectively. The highest methyl ester content (94.09%) was achieved by the addition of THF: methanol = 2:1, CPO: methanol molar ratio = 1:6 and 4 wt% catalyst weight. The results obtained in this study indicate that a green catalyst made from kapok skin can be used to produce biodiesel and also the addition of co-solvent can increase the yield of methyl esters, so that high purity is obtained.

Fabrication of 4N5 Grade Tantalum Wire from Tantalum Scrap by EBM and Drawing

Yu Ji-Won, Choi Sang-Hoon, Sim Jae-Jin, Lim Jae-Hong, Seo Kyoung-Deok, Hyun Soong-Keon, Kim Tae-Youb, Gu Bon-Woo, Park Kyoung-Tae

Archives of Metallurgy and Materials

2019

Vol. 64, iss. 3

935--941

Electron beam melting(EBM) is a useful technique to obtain high-purity metal ingots. It is also used for melting refractory metals such as tantalum, which require melting techniques employing a high-energy heat source. Drawing is a method which is used to convert the ingot into a wire shape. The required thickness of the wire is achieved by drawing the ingot from a drawing die with a hole of similar size. This process is used to achieve high purity tantalum springs, which are an essential component of lithography lamp in semiconductor manufacturing process. Moreover, high-purity tantalum is used in other applications such as sputtering targets for semiconductors. Studies related to recycling of tantalum from these components have not been carried outuntil now. The recycling of tantalum is vital for environmental and economic reasons. In order to obtain high-purity tantalum ingot, in this study impurities contained in the scrap were removed by electron beam melting after pre-treatment using aqua regia. The purity of the ingot was then analyzed to be more than 4N5 (99.995%). Subsequently, drawing was performed using the rod melted by electron beam melting. Owing to continuous drawing, the diameter of the tantalum wire decreased to 0.5 mm from 9 mm. The hardness and oxygen concentration of the tantalum ingot were 149 Hv and less than 300 ppm, respectively, whereas the hardness of the tantalum wire was 232.12 Hv. In conclusion, 4N5 grade tantalum wire was successfully fabricated from tantalum scrap by EBM and drawing techniques. Furthermore, procedure to successfully recycle Tantalum from scraps was established.

Study On The Electro-Refining Of Tin In Acid Solution From Electronic Waste

Son S. H., Park S. C., Kim J. H., Kim Y. H., Lee M. S., Ahn J.-W.

Archives of Metallurgy and Materials

2015

Vol. 60, iss. 2B

1217--1220

The tin metal could be retractable from wasted tin scrap, sludge, and wasted electroplated solution hydrometallurgical treatment, and purification process. In order to be used as resource of electronic devices, the retracted crude metal should be purified to the extent of higher than 99.9%. In this study, tin electro-refining process was performed to purify the casted tin crude metal at various experimental conditions: at the current density of 3, 5A/dm2, and in various electrolytes such as hydrochloric acid, sulfuric acid and methansulfonic acid. Additional experiment was conducted using Rotating Disk Electrode (RDE) in order to investigate the rate determining step of tin electro-refining process. The current efficiency, 65.6%, was achievable at the condition of current density, 5A/dm2, and in the electrolyte of Hydrochloric acid. During tin electro-refining process, impurity dissolved from tin crude metal into the electrolyte was analyzed using Inductively Coupled Plasma Optical Emission Spectrometer (ICP-OES), and the result showed the concentration of impurity metal gradually increased. Quantitative analysis on casted tin crude metal showed that it consists of tin with 93.9 wt.% and several impurity metals of Ag, Bi, Pb, Cu, and etc. After tin electro-refining process, the purity of tin increased up to 99.985 wt.%.