Adsorption of a Polyaromatic Compound on Silica Surfaces from Organic Solvents Studied by Molecular Dynamics Simulation and AFM Imaging

作者：Xiong, Yong; Cao, Tiantian; Chen, Qian; Li, Zhen; Yang, Yue; Xu, Shengming^*; Yuan, Shiling; Sjoeblom, Johan; Xu, Zhenghe^*

来源：Journal of Physical Chemistry C, 2017, 121(9): 5020-5028.

DOI：10.1021/acs.jpcc.6b11763

• OIL-WATER INTERFACE
• ASPHALTENE ADSORPTION
• CRUDE-OIL
• FORCES APPARATUS
• CHAIN-LENGTH
• AGGREGATION
• NANOAGGREGATION
• DETACHMENT
• KAOLINITE
• HYDRATION

Molecular dynamics simulation was used to investigate the adsorption of a polyaromatic compound (CSPe) on silica surfaces from organic solvents. Heptane and toluene were used as oil phase to probe the effect of solvent properties on CSPe adsorption. The results showed that CSPe molecules tend to adsorb rapidly on silica surface in heptane and assemble to form long strip shaped aggregates, while in toluene CSPe prefers to form aggregates which remain mostly in bulk oil phase. The van der Waals interactions were found to provide the largest contribution for driving the adsorption of CSPe from heptane solutions due to the protonated state of CSPe molecules. The calculated lower system free energy of CSPe adsorption from heptane than from toluene corresponded well with the observed stronger adsorption of C5Pe from heptane than from toluene. AFM imaging confirmed the observed trend of C5Pe adsorption on silica from heptane and toluene.

• 出版日期2017-3-9
• 单位山东大学; 清华大学