TY - JOUR
T1 - Changes in Composition and Molecular Structures of Atmospheric Residues during Hydrotreating
AU - Cui, Qingyan
AU - Ma, Xiaoliang
AU - Nakabayashi, Koji
AU - Nakano, Koji
AU - Miyawaki, Jin
AU - Al-Mutairi, Adel
AU - Marafi, Abdulazeem M.J.
AU - Al-Otaibi, Ahmed M.
AU - Yoon, Seong Ho
AU - Mochida, Isao
N1 - Funding Information:
The authors acknowledge the Japan Cooperation Center, the Petroleum (JCCP), the Kuwait Oil Company (KOC), and the Kuwait Institution for Scientific Research (KISR) for financing this research. The acknowledgement is also extended to the Kuwait National Petroleum Company (KNPC) for the kind contribution and technical support.
Publisher Copyright:
Copyright © 2019 American Chemical Society.
PY - 2019/11/21
Y1 - 2019/11/21
N2 - Better understanding of the changes in composition and molecular structures of atmospheric residue (AR) during hydrotreating is important for improving the hydrotreating performance of AR. Hydrotreating of an AR was carried out in a series of fixed bed reactors loaded with hydrodemetallization (HDM) and hydrodesulfurization (HDS) catalysts. The AR and its products were fractionated into saturates, aromatics, resins, and asphaltenes (SARA) and analyzed by using the gel permeation chromatography with an ultraviolet detector (GPC-UV) and with an inductively coupled plasma mass spectrometer (GPC), X-ray diffraction (XRD), 13C nuclear magnetic resonance (13C NMR), and electron spin resonance (ESR). Hydrotreating not only decreased the contents of S, N, V, Ni, resins, and asphaltenes, but also changed the composition, structure, and distribution of the remaining resins and asphaltenes as well as the remaining S, N, V, and Ni compounds in AR products. Almost all metals (V and Ni) existed in both resin (47%) and asphaltene (53%) fractions of AR, whereas in the final hydrotreated product, more than 84% of the remaining metals, which are considered as the most refractory metal compounds, were in the asphaltenes, especially those with larger molecular size. The metal compounds in resins were easier to be removed. The low HDM reactivity of the remaining metal compounds can be attributed to their larger molecular size, which inhibited their approach to the active sites of the catalysts.
AB - Better understanding of the changes in composition and molecular structures of atmospheric residue (AR) during hydrotreating is important for improving the hydrotreating performance of AR. Hydrotreating of an AR was carried out in a series of fixed bed reactors loaded with hydrodemetallization (HDM) and hydrodesulfurization (HDS) catalysts. The AR and its products were fractionated into saturates, aromatics, resins, and asphaltenes (SARA) and analyzed by using the gel permeation chromatography with an ultraviolet detector (GPC-UV) and with an inductively coupled plasma mass spectrometer (GPC), X-ray diffraction (XRD), 13C nuclear magnetic resonance (13C NMR), and electron spin resonance (ESR). Hydrotreating not only decreased the contents of S, N, V, Ni, resins, and asphaltenes, but also changed the composition, structure, and distribution of the remaining resins and asphaltenes as well as the remaining S, N, V, and Ni compounds in AR products. Almost all metals (V and Ni) existed in both resin (47%) and asphaltene (53%) fractions of AR, whereas in the final hydrotreated product, more than 84% of the remaining metals, which are considered as the most refractory metal compounds, were in the asphaltenes, especially those with larger molecular size. The metal compounds in resins were easier to be removed. The low HDM reactivity of the remaining metal compounds can be attributed to their larger molecular size, which inhibited their approach to the active sites of the catalysts.
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U2 - 10.1021/acs.energyfuels.9b02692
DO - 10.1021/acs.energyfuels.9b02692
M3 - Article
AN - SCOPUS:85074230172
VL - 33
SP - 10787
EP - 10794
JO - Energy & Fuels
JF - Energy & Fuels
SN - 0887-0624
IS - 11
ER -