scholarly journals Inference of Reaction Kinetics for Supercritical Water Heavy Oil Upgrading with a Two-phase Stirred Reactor Model

Author(s):  
Ashwin Raghavan ◽  
Ping He ◽  
Ahmed Ghoniem

We present the development and application of a two-phase stirred reactor model for heavy oil upgrading in the presence of supercritical water (SCW), with coupled phase-specific thermolysis reaction kinetics and multicomponent hydrocarbon water phase equilibrium. We demonstrate the inference of oil and water phase kinetics parameters for a compact lumped reaction kinetics model through the application of this model to two different sets of batch reactor experiments reported in the literature. We infer that, though SCW can suppress the formation of newer polynuclear aromatics (PNA) from distillate range species, it is broadly ineffective in deterring the combination of pre-existing PNA fragments in the oil feed. Quantification of the conversion to distillate liquids before the onset of coke formation helps arrive at a clearer conclusion on whether the use of SCW in the batch reactor leads to better product outcomes for different oil feeds and operating conditions.

2019 ◽  
Vol 152 ◽  
pp. 104569 ◽  
Author(s):  
Ramazan Oğuz Canıaz ◽  
Serhat Arca ◽  
Muzaffer Yaşar ◽  
Can Erkey

2020 ◽  
Vol 165 ◽  
pp. 104961
Author(s):  
Seungjae Sim ◽  
Won Bae Kong ◽  
Jonghyeon Kim ◽  
Jimoon Kang ◽  
Hwi-Sung Lee ◽  
...  

2017 ◽  
Vol 126 ◽  
pp. 55-64 ◽  
Author(s):  
Oxana N. Fedyaeva ◽  
Vladimir R. Antipenko ◽  
Anatoly A. Vostrikov

Energies ◽  
2020 ◽  
Vol 13 (17) ◽  
pp. 4553 ◽  
Author(s):  
Ane Caroline Pereira Borges ◽  
Jude Azubuike Onwudili ◽  
Heloysa Andrade ◽  
Carine Alves ◽  
Andrew Ingram ◽  
...  

Nickel iron oxide (NiFe2O4) catalyst was prepared by the combustion reaction method and characterized by XRD, N2 adsorption/desorption, thermogravimetric analysis (TG), and temperature programmed reduction (TPR). The catalyst presented a mixture of oxides, including the NiFe2O4 spinel and specific surface area of 32.4 m2 g−1. The effect of NiFe2O4 catalyst on the supercritical water gasification (SCWG) of eucalyptus wood chips was studied in a batch reactor at 450 and 500 °C without catalyst and with 1.0 g and 2.0 g of catalyst and 2.0 g of biomass for 60 min. In addition, the recyclability of the catalyst under the operating conditions was also tested using recovered and recalcined catalysts over three reaction cycles. The highest amount of H2 was 25 mol% obtained at 450 °C, using 2 g of NiFe2O4 catalyst. The H2 mol% was enhanced by 45% when compared to the non-catalytic test, showing the catalytic activity of NiFe2O4 catalyst in the WGS and the steam reforming reactions. After the third reaction cycle, the results of XRD demonstrated formation of coke which caused the deactivation of the NiFe2O4 and consequently, a 13.6% reduction in H2 mol% and a 5.6% reduction in biomass conversion.


Author(s):  
Mohammad M. Hossain

Abstract This article deals with the upgrading of bitumen in supercritical water (SCW) using a ZrO2-Al2O3-FeOx catalyst in a batch autoclave reactor. The feed bitumen is diluted using different amount of benzene as solvent in order to provide intimate contact between the solid catalyst particles. It also facilitates the diffusion of the heavy molecules into the catalyst particles. The batch reactor results show that the extra heavy oil is slightly decreased with increasing the bitumen concentration from 20 wt % to 30 wt%. No significant change in the product is observed when bitumen concentration is increased above 30 wt% level. However, the coke concentration is increased with increasing bitumen in the feed. The catalyst deactivation is also higher at higher bitumen concentrations (above 20 wt %). XRD analysis reveals that at high bitumen concentrations (above 30 wt %), transformation of magnetite into hematite is lower than that of hematite to magnetite due to consumption of lattice oxygen by the additional hydrocarbons, which also causes the catalyst deactivation. On the contrary, lower bitumen concentration (~10 wt %) maintains hematite as main phase, which is the desirable for sustained catalytic activity for the oxidative cracking reaction. It is believed that SCW acts as source of reactive hydrogen and oxygen species that favors the upgrading process. The reactive hydrogen species react with cracked hydrocarbons to produce stable lighter liquid products. On the other hand, the reactive oxygen species react with oxygen depleted catalysts, which transforms magnetite into hematite and keep the catalyst active.


AIChE Journal ◽  
2014 ◽  
Vol 61 (3) ◽  
pp. 857-866 ◽  
Author(s):  
Xue-Cai Tan ◽  
Qing-Kun Liu ◽  
Dao-Qi Zhu ◽  
Pei-Qing Yuan ◽  
Zhen-Min Cheng ◽  
...  

2008 ◽  
Vol 51 (5) ◽  
pp. 309-314 ◽  
Author(s):  
Shinsuke Kokubo ◽  
Koji Nishida ◽  
Akinori Hayashi ◽  
Hirokazu Takahashi ◽  
Osami Yokota ◽  
...  

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