Simulation of Organic Liquid Products Deoxygenation by Multistage Countercurrent Absorber/Stripping Using CO2 as Solvent with Aspen-HYSYS: Thermodynamic Data Basis and EOS Modeling.

Elinéia Castro Costa,Welisson De Araújo Silva,Vânia Maria Borges Cunha,Andréia De Andrade Mâncio,Eduardo Gama Ortiz Menezes,Marcelo Costa Santos,Sílvio Alex Pereira Da Mota,Marcilene Paiva Da Silva,Marilena Emmi Araújo,Nélio Teixeira Machado

doi:10.3390/molecules26144382

Elinéia Castro Costa, Welisson De Araújo Silva + Show 8 more

Open Access

https://doi.org/10.3390/molecules26144382

Copy DOI

Abstract

In this work, the thermodynamic data basis and equation of state (EOS) modeling necessary to simulate the fractionation of organic liquid products (OLP), a liquid reaction product obtained by thermal catalytic cracking of palm oil at 450 °C, 1.0 atmosphere, with 10% (wt.) Na2CO3 as catalyst, in multistage countercurrent absorber/stripping columns using supercritical carbon dioxide (SC-CO2) as solvent, with Aspen-HYSYS was systematically investigated. The chemical composition of OLP was used to predict the density (ρ), boiling temperature (Tb), critical temperature (Tc), critical pressure (Pc), critical volume (Vc), and acentric factor (ω) of all the compounds present in OLP by applying the group contribution methods of Marrero-Gani, Han-Peng, Marrero-Pardillo, Constantinou-Gani, Joback and Reid, and Vetere. The RK-Aspen EOS used as thermodynamic fluid package, applied to correlate the experimental phase equilibrium data of binary systems OLP-i/CO2 available in the literature. The group contribution methods selected based on the lowest relative average deviation by computing Tb, Tc, Pc, Vc, and ω. For n-alkanes, the method of Marrero-Gani selected for the prediction of Tc, Pc and Vc, and that of Han-Peng for ω. For alkenes, the method of Marrero-Gani selected for the prediction of Tb and Tc, Marrero-Pardillo for Pc and Vc, and Han-Peng for ω. For unsubstituted cyclic hydrocarbons, the method of Constantinou-Gani selected for the prediction of Tb, Marrero-Gani for Tc, Joback for Pc and Vc, and the undirected method of Vetere for ω. For substituted cyclic hydrocarbons, the method of Constantinou-Gani selected for the prediction of Tb and Pc, Marrero-Gani for Tc and Vc, and the undirected method of Vetere for ω. For aromatic hydrocarbon, the method of Joback selected for the prediction of Tb, Constantinou-Gani for Tc and Vc, Marrero-Gani for Pc, and the undirected method of Vetere for ω. The regressions show that RK-Aspen EOS was able to describe the experimental phase equilibrium data for all the binary pairs undecane-CO2, tetradecane-CO2, pentadecane-CO2, hexadecane-CO2, octadecane-CO2, palmitic acid-CO2, and oleic acid-CO2, showing average absolute deviation for the liquid phase () between 0.8% and 1.25% and average absolute deviation for the gaseous phase () between 0.01% to 0.66%.

Highlights

The organic liquid products (OLP) obtained by thermal catalytic cracking of lipid-base materials, including vegetable oils [1–17], residual oils [18–25], animal fats [26–28], residual animal fat [27], mixtures of carboxylic acids [28–33], soaps of carboxylic acids [34,35], and scum, grease & fats [36–38], may be used as liquid fuels [1,2,4–8,10,11,13–20,22,26,35–41], if proper upgrading processes are applied to remove the oxygenates [6,7,10,16–19,35–41]
The RK-Aspen equation of state (EOS) was able to describe the high-pressure phase equilibria of multicomponent system olive oil-CO2 [90], showing RMSD between 3E-07 to 0.0138 for the liquid phase and between 0.0009 to 2E-04 for the gaseous phase, by considering the system was represented by the multicomponent model mixture triolein-squalene-oleic acid-CO2
The results show the precision of RK-Aspen EOS to describe the multicomponent system for the state conditions (T, P), and free fatty acid (FFA) content in feed

Summary

Introduction

The OLP obtained by thermal catalytic cracking of lipid-base materials, including vegetable oils [1–17], residual oils [18–25], animal fats [26–28], residual animal fat [27], mixtures of carboxylic acids [28–33], soaps of carboxylic acids [34,35], and scum, grease & fats [36–38], may be used as liquid fuels [1,2,4–8,10,11,13–20,22,26,35–41], if proper upgrading processes (distillation, adsorption, and liquid-liquid extraction) are applied to remove the oxygenates [6,7,10,16–19,35–41]. Modern design of equilibrium stage processes (e.g., fractionation of multi-component liquid mixtures by multistage countercurrent absorber/stripping columns using supercritical CO2 as solvent) requires thermodynamic models capable of predicting the chemical composition of the coexisting phases without the preliminary use of experimental data. The RK-Aspen EOS with the van der Waals mixing rules and RK-Aspen combining rules for two temperature-independent binary interaction parameters kaij = k0aij and Molecules 2021, 26, 4382 kbij = k0bij, and the kij between two components i and j is a function of the pure component critical properties (Tci, Tcj, Pci, Pcj) and acentric factors (ωi, ωj) In this sense, it is necessary to compute the critical properties and acentric factors of all the chemical species present in the composition of complex/multi-component mixture [46]. To estimate the critical pressure (Pc), and likewise the method by Joback and Reid [63], this method considers the number of atoms in the molecule

Methods

17 Est of

Findings

Conclusions