Facial reconstruction

Search LJMU Research Online

Browse Repository | Browse E-Theses

Chemical characterizations and molecular dynamics simulations on different rejuvenators for aged bitumen recycling

Ren, S, Liu, X, Lin, P, Erkens, S and Gao, Y (2022) Chemical characterizations and molecular dynamics simulations on different rejuvenators for aged bitumen recycling. Fuel, 324. ISSN 0016-2361

Full text not available from this repository. Please see publisher or open access link below:
Open Access URL: https://doi.org/10.1016/j.fuel.2022.124550 (Published version)


Molecular dynamics (MD) simulation is an advanced tool to explore the interaction mechanism between aged bitumen and rejuvenators at the nanoscale. However, the general MD molecular structures of rejuvenators led to the lower quantify and inaccuracy of the simulation outputs. This study aims at developing more realistic molecular models to represent the generic rejuvenators for MD simulation of aged bitumen recycling. Four types of rejuvenators (bio-oil, engine-oil, naphthenic-oil, and aromatic-oil) are characterized in terms of element analysis, functional groups distribution observed from Attenuated total reflectance-Fourier-transform infrared (ATR-FTIR) spectroscopy, and average molecular weight. Afterward, the average molecular structures of rejuvenators are determined and validated. Further, the MD simulations are performed to predict the energetic, dynamic, volumetric, and structural properties of various rejuvenators. Based on the chemical characteristics, the average chemical formula of bio-oil, engine-oil, naphthenic-oil, and aromatic-oil is derived as C19H36O2, C22H44, C26H48, C30H40. From MD simulations, the ranking of density and glass transition temperature for four different rejuvenators is AO > NO > BO > EO, which is same as the experimental results. It proves that the established average molecular structures of four rejuvenators are reasonable. Various rejuvenators display different thermodynamics and structural properties. The aromatic-oil exhibits the highest potential energy, cohesive energy density, and solubility parameter. Besides, the order of expansion coefficient and diffusion coefficient of the four rejuvenators is the same as BO > EO > NO > AO, while the viscosity presents the opposite sequence. Moreover, the fractional free volume values follow EO > BO > NO > AO. The occurrence probability between bio-oil and aromatic-oil molecules is higher than engine-oil and naphthenic-oil. This study develops the representative average molecular models for generic rejuvenators and helps understand the difference in chemo-physical and thermodynamics properties among various rejuvenators.

Item Type: Article
Uncontrolled Keywords: 0306 Physical Chemistry (incl. Structural); 0904 Chemical Engineering; 0913 Mechanical Engineering; Energy
Subjects: T Technology > TP Chemical technology
Divisions: Civil Engineering & Built Environment
Publisher: Elsevier BV
SWORD Depositor: A Symplectic
Date Deposited: 17 May 2023 13:53
Last Modified: 17 May 2023 13:53
DOI or ID number: 10.1016/j.fuel.2022.124550
URI: https://researchonline.ljmu.ac.uk/id/eprint/19514
View Item View Item