Supercritical Water Treatment of Crude Oil and Hexylbenzene: An Experimental and Mechanistic Study on Alkylbenzene Decomposition

被引：23

作者：

Carr, Adam G. ^{[1
]}

Class, Caleb A. ^{[2
]}

Lai, Lawrence ^{[2
]}

Kida, Yuko ^{[2
]}

Monrose, Tamba ^{[2
]}

Green, William H. ^{[2
]}

机构：

[1] Aerodyne Res Inc, Billerica, MA 01821 USA

[2] MIT, Cambridge, MA 02139 USA

来源：

ENERGY & FUELS | 2015年 / 29卷 / 08期

关键词：

2-DIMENSIONAL GAS-CHROMATOGRAPHY; CRACKING; CLEAVAGE;

D O I：

10.1021/acs.energyfuels.5b01040

中图分类号：

TE [石油、天然气工业]; TK [能源与动力工程];

学科分类号：

0807 ; 0820 ;

摘要：

High concentrations of fuel-range hydrocarbons may be recovered from heavier alkyl-aromatic compounds in crude oil after supercritical water (SCW) treatment. Arabian Heavy (AN) crude oil was treated in SCW and analyzed using two-dimensional gas chromatography (GC x GC-FID). Cracking mechanisms were investigated using the model compound hexylbenzene under similar SCW treatment conditions. The results of the model compound experiments were compared to predictions of a kinetic model built by the Reaction Mechanism Generator (RMG). AN crude cracked significantly during SCW treatment. The GC-observable mass fraction increased by 90%. We conducted studies on the distilled samples of crude oil and found that significant changes in the composition of the SCW-treated heavy fraction occurred. Significant formation of aliphatic hydrocarbons and small-chain BTX-type compounds were found in the SCW-processed samples. Hexylbenzene conversions differed between the crude oil studies and the model compound studies. The mechanistic model for the cracking of hydrocarbons during SCW treatment of the model compound hexylbenzene predicted the observed major liquid products toluene, styrene, and ethylbenzene. The selectivity of ethylbenzene and styrene changed over time. The apparent conversion of styrene into ethylbenzene was possibly via a reverse disproportionation reaction. Ultimately, a mechanism was built that serves as a basis for understanding the kinetics of hydrocarbon cracking in SCW.

引用

页码：5290 / 5302

页数：13

共 29 条

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