Journal article
Study of asphaltene precipitation by Calorimetry
Department of Chemical and Biochemical Engineering, Technical University of Denmark1
Center for Phase Equilibria and Separation Processes, Department of Chemical and Biochemical Engineering, Technical University of Denmark2
Center for Energy Resources Engineering, Centers, Technical University of Denmark3
Can calorimetry bring new input to the Current understanding of asphaltene precipitation? In this work, two types of precipitation were studied by means of calorimetry: addition of n-heptane into asphaltene solutions and temperature/pressure variations on a recombined live oil. The first series of experiments showed that weak forces determine precipitation.
Indeed, isothermal titration calorimetry could not detect any clear signal although this technique can detect low-energy transitions such as liquid-liquid equilibrium and rnicellization. The second series of tests proved that precipitation caused by T and P variations is exothermic for this system. Furthermore, the temperature-induced precipitation is accompanied by an increase in the apparent thermal expansivity.
Therefore, it seems that these two phase transitions exhibit different calorimetric behaviours and they may not be as similar as expected.
Language: | English |
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Year: | 2007 |
Pages: | 3583-3587 |
ISSN: | 15205029 and 08870624 |
Types: | Journal article |
DOI: | 10.1021/ef700316e |
ORCIDs: | Andersen, Simon Ivar and Stenby, Erling Halfdan |