title: Influence of Polyphosphoric Acid on the Consistency and Composition of Formulated Bitumen: Standard Characterization and NMR Insights.
abstract: Over the recent years, bitumen modification with polymers, acids, or mineral fillers has gained relevance to adjust its performance properties. This work reports the use of polyphosphoric acid (PPA) for the modification of formulated bitumen. With this objective, an in-depth literature review on PPA modification was firstly performed. Subsequently, five individual refinery components were selected for the preparation of bitumen blends, namely, asphaltic residue, vacuum residue, and three lube oils extracts. Seven binary/ternary bitumen blends were prepared and then treated with PPA. Afterwards, the five components and the unmodified and PPA-modified bitumen were characterized by standard methods (penetration, softening point, and penetration index), SARA analysis, elemental analysis, and (31)P and (1)H nuclear magnetic resonance (NMR) spectroscopy. The results evidenced higher asphaltenes and lower saturates/resins contents in PPA-modified bitumen. The NMR data suggest that the paraffinic chains became longer, the content of condensed aromatics increased, more substituted aromatic structures appeared, and α-hydrogen in aromatic structures diminished. These findings disclosed the improved consistency and oxidation stability of PPA-modified bitumen blends.
authors: Department of Chemistry, CICECO-Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal; Galp Energia, Refinaria de Matosinhos, Rua Belchior Robles, 4450-802 Leça da Palmeira, Portugal.
authors: Catarina
authors: C
authors: Varanda
authors: Department of Chemistry, CICECO-Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal.
authors: Inês
authors: 0000-0003-0767-721X
authors: I
authors: Portugal
authors: Galp Energia, Refinaria de Matosinhos, Rua Belchior Robles, 4450-802 Leça da Palmeira, Portugal.
authors: Jorge
authors: J
authors: Ribeiro
authors: Department of Chemistry, QOPNA, University of Aveiro, 3810-193 Aveiro, Portugal.
authors: Artur M S
authors: 0000-0003-2861-8286
authors: AM
authors: Silva
authors: Department of Chemistry, CICECO-Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal.
authors: Carlos M
authors: 0000-0002-9310-2457
authors: CM
authors: Silva