TY - JOUR

T1 - In Situ FTIR Spectroscopic Imaging of Asphaltene Deposition from Crude Oil under n-Heptane and Acetone Flows

AU - Shalygin, A. S.

AU - Milovanov, E. S.

AU - Kovalev, E. P.

AU - Yakushkin, S. S.

AU - Kazarian, S. G.

AU - Martyanov, O. N.

N1 - Funding Information: A.S. Shalygin and E.P. Kovalev thank the Russian Science Foundation for financial support (project no. 20-79-00183, 2020 Competition for projects for the event “Conducting Initiative Research by Young Scientists” of the Presidential Program of Research Projects Implemented by Leading Scientists, Including Young Scientists) and the National Center for Catalyst Research, Collective Use Center, for the provided equipment. Publisher Copyright: © 2022, The Author(s).

PY - 2022/9

Y1 - 2022/9

N2 - Asphaltene deposition from crude oil, induced by n-heptane and acetone flows in a microfluidic device, was studied by optical and FTIR spectroscopic imaging techniques in situ. It was found that n-heptane and acetone penetrate crude oil in completely different ways, which is responsible for the formation of deposits with different structures and chemical compositions. The contact of the n-heptane flow with crude oil leads to fast aggregation of asphaltenes at the interface, resulting in the formation of a compact deposit fixed to the surface. Subsequent slow diffusion of n-heptane into crude oil causes asphaltene aggregation and precipitation of loose deposits. In the case of acetone, the flocculant diffuses (faster than n-heptane) into crude oil, which results in removal of its soluble components and in the formation of deposits appearing as strips as well. The distribution of the functional groups (–OH(NH), CH2–CH3, C=O, C–O, S=O) in the deposits is spatially heterogeneous. The asphaltenes deposits formed at the flocculant-crude oil interface are richer in the functional groups than those formed during diffusion. No carbonyl groups were revealed in the deposits formed in the acetone flow, while oxygen-containing groups such as –OH(NH) and S=O were present, which was an unusual result.

AB - Asphaltene deposition from crude oil, induced by n-heptane and acetone flows in a microfluidic device, was studied by optical and FTIR spectroscopic imaging techniques in situ. It was found that n-heptane and acetone penetrate crude oil in completely different ways, which is responsible for the formation of deposits with different structures and chemical compositions. The contact of the n-heptane flow with crude oil leads to fast aggregation of asphaltenes at the interface, resulting in the formation of a compact deposit fixed to the surface. Subsequent slow diffusion of n-heptane into crude oil causes asphaltene aggregation and precipitation of loose deposits. In the case of acetone, the flocculant diffuses (faster than n-heptane) into crude oil, which results in removal of its soluble components and in the formation of deposits appearing as strips as well. The distribution of the functional groups (–OH(NH), CH2–CH3, C=O, C–O, S=O) in the deposits is spatially heterogeneous. The asphaltenes deposits formed at the flocculant-crude oil interface are richer in the functional groups than those formed during diffusion. No carbonyl groups were revealed in the deposits formed in the acetone flow, while oxygen-containing groups such as –OH(NH) and S=O were present, which was an unusual result.

KW - acetone

KW - asphaltenes

KW - chemical imaging

KW - crude oil

KW - FTIR spectroscopic imaging

KW - microfluidic device

KW - n-heptane

UR - http://www.scopus.com/inward/record.url?scp=85141792422&partnerID=8YFLogxK

UR - https://www.mendeley.com/catalogue/959ed4ee-f134-31e0-9b77-191b71e15910/

U2 - 10.1134/S0965544122090079

DO - 10.1134/S0965544122090079

M3 - Article

AN - SCOPUS:85141792422

VL - 62

SP - 1087

EP - 1095

JO - Petroleum Chemistry

JF - Petroleum Chemistry

SN - 0965-5441

IS - 9

ER -