A stochastic reconstruction strategy based on a stratified library of structural descriptors and its application in the molecular reconstruction of naphtha

doi:10.1016/j.cjche.2021.12.020

中国化学工程学报 ›› 2022, Vol. 51 ›› Issue (11): 153-167.DOI: 10.1016/j.cjche.2021.12.020

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A stochastic reconstruction strategy based on a stratified library of structural descriptors and its application in the molecular reconstruction of naphtha

Guangyao Zhao, Minglei Yang, Wenli Du, Feifei Shen, Feng Qian

Key Laboratory of Smart Manufacturing in Energy Chemical Process, Ministry of Education, East China University of Science and Technology, Shanghai 200237, China

收稿日期:2021-07-19 修回日期:2021-12-22 出版日期:2022-11-18 发布日期:2023-01-18
通讯作者: Minglei Yang,E-mail:mlyang@ecust.edu.cn;Feng Qian,E-mail:fqian@ecust.edu.cn
基金资助:
The authors are grateful for the support of International (Regional) Cooperation and Exchange Project (61720106008), National Natural Science Fund for Distinguished Young Scholars (61925305), and National Natural Science Foundation of China (61873093).

A stochastic reconstruction strategy based on a stratified library of structural descriptors and its application in the molecular reconstruction of naphtha

Guangyao Zhao, Minglei Yang, Wenli Du, Feifei Shen, Feng Qian

Key Laboratory of Smart Manufacturing in Energy Chemical Process, Ministry of Education, East China University of Science and Technology, Shanghai 200237, China

Received:2021-07-19 Revised:2021-12-22 Online:2022-11-18 Published:2023-01-18
Contact: Minglei Yang,E-mail:mlyang@ecust.edu.cn;Feng Qian,E-mail:fqian@ecust.edu.cn
Supported by:
The authors are grateful for the support of International (Regional) Cooperation and Exchange Project (61720106008), National Natural Science Fund for Distinguished Young Scholars (61925305), and National Natural Science Foundation of China (61873093).

摘要/Abstract

摘要： Molecular reconstruction is a rapid and reliable way to provide molecular detail of petroleum fractions, which is required in the kinetic modeling of petroleum conversation processes at the molecular level. In the typical stochastic reconstruction method, the estimation of properties of pseudo molecules that are generated by Monte Carlo sampling depends on the building of predefined molecular libraries, which is expensive and inaccessible for certain petroleum fractions. In this paper, a novel stochastic reconstruction strategy is proposed, which is based on a stratified library of structural descriptors. Properties of pseudo molecules generated in the novel strategy can be directly estimated by group contribution method in the condition of lacking predefined molecular libraries. In this strategy, the molecular building diagram comprises two steps. First, the ring structure is configured by determining the number of rings. Different from the length of chain adopted in the traditional stochastic reconstruction method, in the second step, number of structural descriptors (SDs) for binding site and chain were determined sequentially for the configuration of binding site and saturated acyclic hydrocarbon chain. These structural descriptors for binding site and chain were selected from group contribution methods. To count the number of partial overlapping sections between structural descriptors for chain, two supplementary structural descriptors were created. All possible saturated structures of hydrocarbon chains can be represented by structural descriptors at the scale of property estimation. This strategy separates the building of a predefined molecule library from the stochastic reconstruction process. The exact structures of pseudo molecules represented by structural descriptors in this work can be determined with sufficient chemical knowledge. Fifty naphtha samples are tested independently to demonstrate the performance of the proposed strategy and the results show that the estimated properties were close enough to the experimental values. This strategy will benefit the molecular management of petrochemical industries and therefore improve economic and environmental efficiencies.

关键词: Novel stochastic reconstruction strategy, Stratified library of structural descriptors, Group contribution method

Abstract: Molecular reconstruction is a rapid and reliable way to provide molecular detail of petroleum fractions, which is required in the kinetic modeling of petroleum conversation processes at the molecular level. In the typical stochastic reconstruction method, the estimation of properties of pseudo molecules that are generated by Monte Carlo sampling depends on the building of predefined molecular libraries, which is expensive and inaccessible for certain petroleum fractions. In this paper, a novel stochastic reconstruction strategy is proposed, which is based on a stratified library of structural descriptors. Properties of pseudo molecules generated in the novel strategy can be directly estimated by group contribution method in the condition of lacking predefined molecular libraries. In this strategy, the molecular building diagram comprises two steps. First, the ring structure is configured by determining the number of rings. Different from the length of chain adopted in the traditional stochastic reconstruction method, in the second step, number of structural descriptors (SDs) for binding site and chain were determined sequentially for the configuration of binding site and saturated acyclic hydrocarbon chain. These structural descriptors for binding site and chain were selected from group contribution methods. To count the number of partial overlapping sections between structural descriptors for chain, two supplementary structural descriptors were created. All possible saturated structures of hydrocarbon chains can be represented by structural descriptors at the scale of property estimation. This strategy separates the building of a predefined molecule library from the stochastic reconstruction process. The exact structures of pseudo molecules represented by structural descriptors in this work can be determined with sufficient chemical knowledge. Fifty naphtha samples are tested independently to demonstrate the performance of the proposed strategy and the results show that the estimated properties were close enough to the experimental values. This strategy will benefit the molecular management of petrochemical industries and therefore improve economic and environmental efficiencies.

Key words: Novel stochastic reconstruction strategy, Stratified library of structural descriptors, Group contribution method

Guangyao Zhao, Minglei Yang, Wenli Du, Feifei Shen, Feng Qian. A stochastic reconstruction strategy based on a stratified library of structural descriptors and its application in the molecular reconstruction of naphtha[J]. 中国化学工程学报, 2022, 51(11): 153-167.

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A stochastic reconstruction strategy based on a stratified library of structural descriptors and its application in the molecular reconstruction of naphtha

A stochastic reconstruction strategy based on a stratified library of structural descriptors and its application in the molecular reconstruction of naphtha

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