Utilization of DSC, NIR, and NMR for wax appearance temperature and chemical additive performance characterization

作者：Zhao Yansong; Paso Kristofer^*; Norrman Jens; Ali Hassan; Sorland Geir; Sjoblom Johan

来源：Journal of Thermal Analysis and Calorimetry, 2015, 120(2): 1427-1433.

DOI：10.1007/s10973-015-4451-1

• DSC
• NIR
• NMR
• Wax appearance temperature
• Wax crystallization

Wax crystallization processes are investigated using differential scanning calorimetry, near-infrared spectroscopy, and nuclear magnetic resonance spectroscopy. The performance of a chemical additive is assessed using calorimetry and NMR. Heat flows of model waxy oils are obtained using differential scanning calorimetry, providing the wax appearance temperature and crystallization profiles. The effect of cooling rate, wax content, asphaltene, and chemical additive on the wax appearance temperature is investigated. The wax appearance temperature increases with increasing wax contents. The wax appearance temperature decreases in the presence of chemical additive, effectively increasing the instantaneous supersaturation. Furthermore, near-infrared spectroscopy and nuclear magnetic resonance spectroscopy are utilized to determine wax appearance temperature. The NMR experiments quantify liquid and solid fractions at thermal equilibrium conditions, effectively circumventing the need for dynamic thermal techniques.

• 出版日期2015-5