4TH International Congress on Technology - Engineering & SCIENCE - Kuala Lumpur - Malaysia (2017-08-05)

Analysis Of Marine Fuels In Seawater Using Fourier Transform Infrared Spectroscopy (ftir)
Marine fuel is a chemical compound composed of long petroleum hydrocarbon, sulfur and trace of inorganic compounds, and it is mostly used in the engine for generation of the power of vessel. The increasing marine traffic by sea and in ports results in the frequent occurrence of some pollution, such as oil spills. This pollution has devastating effects as petroleum hydrocarbons are difficult to clean up and being toxic to marine life. Additionally, residual oil from marine traffic could exist in the marine environment for quite some time. “EPA Method 418.1” [1] commonly used to determine marine fuel is based on CFC-113 extraction. However, this solvent has been banned due to ozone depleting compounds and phased out by 1996. Another common method “MEP GB/T 16488-1996” [2] used tetrachloromethane that became illegal in 2010 as well. The novel extraction dimer/trimer of chlorotrifluoroethylene (S-316) as a substitute was subsequently recommended in ASTM D7066-04[3]. On account of its expensive price [4], it could not be commonly used. Therefore, this paper presents the developed FTIR method for determining marine fuels in seawater by extraction in tetrachloroethylene. Tetrachloroethylene is widely used for dry cleaning of fabrics, and it is an excellent solvent without C-H groups and has no negative environmental effects. The absorption at the peak that occurs around 2930 cm-1 is primarily counting CH2 groups, so the infrared absorbance increases with the length of the hydrocarbon chain that correlates with the weight of the hydrocarbon and presents marine fuel concentration. This developed method uses tetrachloroethylene to extract marine fuels from seawater sample, and then examines a portion of the extract by FTIR to obtain its absorbance at the peak around 2930 cm-1. Calibration is carried out by scanning at least 4 to 5 known calibration solutions, in order to draw a calibration curve plotted by absorbance at 2930 cm-1 versus concentration (ppm). The expected calibration curve should be linear. Otherwise, it is necessary to clean the sample cell or consider adjusting the bounds of calibration standards accordingly. Given verifying the stability and the accuracy of FTIR, calibration should be required to do every time. With calibration curve, sample marine fuel concentration could be measured. This method has been applied to analyze three kinds of marine fuels in the experiment, including MFO 180CST, MFO 380CST, and MFO 500CST. Results have showed that the developed method is accurate and easy to determine the concentration of marine fuels.
Keywords: FTIR, Marine fuel, Tetrachloroethylene
Yingmin Liu, Qishan Liu, Zuolian Cheng, Shijing Xiao, Jeremy Tan,