Polycardanol's potential to deasphalt crude oil: Influence of polymer conversion degree, molar mass, and structure

• Published in: Canadian journal of chemical engineering 2023-11, Vol.101 (11), p.6555-6565
• Main Authors: Martins, Maximiliano F., Aversa, Thiago M., Lucas, Elizabete F.
• Format: Article
• Language: English
• Subjects: Asphaltenes; Cationic polymerization; Conversion; Crude oil; Distillation; Flocculants; Flocculation; Heptanes; Molecular chains; Near infrared radiation; Polymers; Reagents; Synthesis; Titration; Toluene
• ISSN: 0008-4034; 1939-019X
• DOI: 10.1002/cjce.24928

Cardanol is a natural material that acts to stabilize asphaltenes in crude oil. However, its derivative, polycardanol, obtained via cationic polymerization, has divergent behaviour, with reports of its acting both as asphaltenes stabilizer and flocculant. Recently, it was demonstrated that the reaction conditions influence the conversion rates, structures, and molar masses of the products from synthesizing polycardanol initiated with BF 3  · O(C 2 H 5 ) 2 . Seeking to elucidate the influence of these variables on the phase behaviour of asphaltenes, in this work six products, previously synthesized and characterized, had their performance evaluated by asphaltenes precipitation onset, using n ‐heptane titration and monitoring by near‐infrared spectroscopy, using asphaltenes model systems (C5I and C7I) at 1.00 wt./vol.% in toluene. All the products had the ability to flocculate asphaltenes and have potential for deasphalting process. Flocculation efficiency increased with rising molar mass, higher reaction conversion degree, and presence of lateral hydrocarbon chains. The most efficient structures were not affected by the presence of unreacted cardanol. This indicated that the reaction does not require a purification step. Aged cardanol was also able to produce flocculant polymer, indicating that the distillation of cardanol is not required. The cost to obtain a product without needing reagent distillation becomes lower.