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Study on Local Composition of Binary n-Alkane for Precise Estimation of Wax Disappearance Temperature

Natee Sa-ngawong, Tawiwan Kangsadan, Kraipat Cheenkachorn, Nantiya Inwong, Aungsutorn Mahittikul


This work aims to investigate the influence of the pure component parameters of n-alkanes and assumptions for the solid-phase on the accuracy of wax disappearance temperature (WDT) estimation, using five binary mixtures, consist of n-hexane + n-hexadecane, n-octadecane + n-hexadecane, n-tridecane + n-hexane, n-hexadecane + n-tetradecane, and n-octadecane + n-undecane. Perturbed Chain Form of the Statistical Associating Fluid Theory (PC-SAFT) Equation of State (EoS) was implemented to describe solid-liquid equilibrium (SLE) and evaluate its capability for the WDT model. Furthermore, regular solution theory was also applied to SLE description to confirm the prediction from PC-SAFT. The estimated results were compared with the experimental data to examine the accuracy of the provided solution. Reasonable agreement between the predicted and the experimental results was observed. The results were analyzed and theoretical improvement on solutions were suggested.


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DOI: 10.14416/j.asep.2020.02.002


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