scholarly journals ANALYTICAL SOLUTIONS FOR THE BREAKTHROUGH CURVES OF FIXED-BED ADSORBERS UNDER CONSTANT PATTERN AND LINEAR DRIVING FORCE APPROXIMATIONS

1977 ◽  
Vol 10 (6) ◽  
pp. 490-493 ◽  
Author(s):  
KOUICHI MIURA ◽  
KENJI HASHIMOTO
Keyword(s):  
Analytical Solutions ◽  
Driving Force ◽  
Fixed Bed ◽  
Breakthrough Curves ◽  
Linear Driving Force

Linear Driving Force Model in Carbon Dioxide Capture by Adsorption

2016 ◽  
Vol 830 ◽  
pp. 38-45 ◽  
Author(s):  
Leonardo Hadlich de Oliveira ◽  
Joziane Gimenes Meneguin ◽  
Edson Antonio da Silva ◽  
Maria Angélica Simões Dornellas de Barros ◽  
Pedro Augusto Arroyo ◽  
...  
Keyword(s):  
Mass Transfer ◽  
Transfer Coefficient ◽  
Mass Transfer Coefficient ◽  
Breakthrough Curve ◽  
Driving Force ◽  
Fixed Bed ◽  
Isotherm Models ◽  
Force Model ◽  
Transfer Resistance ◽  
Linear Driving Force

In this work, experimental data of CO2 capture by adsorption was determined gravimetrically, at 30 °C and pressures up to 40 bar, and in a fixed bed unit at 20 bar, using NaY as adsorbent. Langmuir, Sips and Tóth isotherm models were used to correlate the equilibrium data. Sips and Tóth models were best fitted allowing estimate the maximum CO2 adsorbed amount. The breakthrough curve was modeled using Linear Driving Force (LDF) and Thomas models. The LDF model represented better the CO2 breakthrough curve than Thomas model. The mass transfer resistance in NaY micropores can be assumed as the limiting step for CO2 adsorption in fixed bed, since the intraparticle mass transfer coefficient of LDF model was smaller than the experimental overall volumetric mass transfer coefficient, although external film resistance is not negligible.

scholarly journals The Effects of Quartic Term Mathematical Model on The Concentration Profile of Fixed Bed Gas Adsorber

2021 ◽  
Vol 15 (1) ◽  
pp. 28
Author(s):  
Ary Mauliva Hada Putri
Keyword(s):  
Mathematical Model ◽  
Concentration Profile ◽  
Driving Force ◽  
Fixed Bed ◽  
Effective Diffusivity ◽  
Porous Solids ◽  
Diffusivity Coefficient ◽  
Parabolic Profile ◽  
Linear Driving Force ◽  
Quartic Term

The need for a reliable mathematical model depicting the process inside a column adsorber has become a requisite in designing an effective gas adsorber. Even though this task can be done by using commercial software, it is still important to get an understanding of how the entire process happens.  In this paper, we discuss a new way to approximate the concentration profile inside the porous solids. It is an extension of the work of Liaw et al., who adopted a parabolic (i.e., quadratic) profile, which is a function of pellet radius while retaining the spherical symmetry. We extend their work by adding the quartic term. The inclusion of this new term still preserves the form of linear driving force approximation with some correction to Glueckauf’s parameter (i.e., the effective diffusivity coefficient). The addition of the correction will affect the breakthrough curve so that it affects the saturation time. In the binary system of hydrogen/methane discussed in this study, we found that a negative correction to the diffusivity coefficient will make the saturation happen earlier compared to that of the parabolic case, and vice versa. This study may help us design an efficient gas purifier, in particular when we set out for the regeneration of the adsorbent.Keywords: activated carbon; effective diffusivity coefficient; hydrogen; linear driving force; methane; parabolic profile A B S T R A KKebutuhan model matematis yang dapat menggambarkan proses penyerapan dalam kolom adsorpsi telah menjadi kebutuhan yang tak terelakkan dewasa ini. Walaupun kini telah tersedia berbagai perangkat lunak komersial, namun tidak dapat dipungkiri bahwa memahami bagaimana proses tersebut terjadi tetap menjadi suatu hal yang berguna. Paper ini bertujuan untuk menampilkan cara baru dalam pemodelan konsentrasi adsorbat di dalam adsorben padat berpori. Kami memperluas metode yang dikembangkan Liaw et al. dengan menambahkan suku pangkat empat (kuartik). Penambahan ini akan mengoreksi koefisien difusivitas efektif dari persamaan linear driving force (LDF). Koreksi yang bernilai negatif, misalnya, akan mengurangi nilai koefisien difusivitas tersebut sehingga akan menghambat kemampuan adsorpsi. Hasil perhitungan kami pada sistem biner hidrogen/ metana menunjukkan bahwa suatu koreksi bernilai negatif dapat menyebabkan saturasi berlangsung lebih cepat dari kasus profil parabolik. Begitu pula sebaliknya, koreksi positif akan menambah daya adsorpsi sehingga saturasi dapat diperlambat. Studi ini kami harapkan dapat diterapkan untuk mendesain suatu kolom adsorpsi yang efisien, terutama dalam perencanaan proses regenerasi adsorben.Kata kunci: hidrogen; karbon aktif; koefisien difusivitas efektif; linear driving force; metana; profil parabolik

Biochar caged zirconium ferrite nanocomposites for the adsorptive removal of Reactive Blue 19 dye in a batch and column reactors and conditions optimizaton

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Shazia Perveen ◽  
Raziya Nadeem ◽  
Shaukat Ali ◽  
Yasir Jamil
Keyword(s):  
Experimental Data ◽  
Low Dose ◽  
Fixed Bed ◽  
Breakthrough Curves ◽  
Adsorption Efficiency ◽  
Fixed Bed Column ◽  
Flow Rates ◽  
Adsorptive Removal ◽  
Reactive Blue 19 ◽  
Pseudo Second Order

Abstract Biochar caged zirconium ferrite (BC-ZrFe2O5) nanocomposites were fabricated and their adsorption capacity for Reactive Blue 19 (RB19) dye was evaluated in a fixed-bed column and batch sorption mode. The adsorption of dye onto BC-ZrFe2O5 NCs followed pseudo-second-order kinetics (R 2 = 0.998) and among isotherms, the experimental data was best fitted to Sips model as compared to Freundlich and Langmuir isotherms models. The influence of flow-rate (3–5 mL min−1), inlet RB19 dye concentration (20–100 mg L−1) and quantity of BC-ZrFe2O5 NCs (0.5–1.5 g) on fixed-bed sorption was elucidated by Box-Behnken experimental design. The saturation times (C t /C o  = 0.95) and breakthrough (C t /C o  = 0.05) were higher at lower flow-rates and higher dose of BC-ZrFe2O5 NCs. The saturation times decreased, but breakthrough was increased with the initial RB19 dye concentration. The treated volume was higher at low sorbent dose and influent concentration. Fractional bed utilization (FBU) increased with RB19 dye concentration and flow rates at low dose of BC-ZrFe2O5 NCs. Yan model was fitted best to breakthrough curves data as compared to Bohart-Adams and Thomas models. Results revealed that BC-ZrFe2O5 nanocomposite has promising adsorption efficiency and could be used for the adsorption of dyes from textile effluents.

Adsorption of Methylene Blue from Solution by Natural Zeolite in Fixed-Bed Column: Effect of Bed Depth

2012 ◽  
Vol 518-523 ◽  
pp. 3115-3119
Author(s):  
Yan Qiang Li ◽  
Xiao Feng Ren ◽  
Shao Hua Chen ◽  
Xiu Rong Zhao ◽  
Run Ping Han
Keyword(s):  
Methylene Blue ◽  
Natural Zeolite ◽  
Fixed Bed ◽  
Breakthrough Curves ◽  
Form Solution ◽  
Column Height ◽  
Nonlinear Regression Analysis ◽  
Adsorption Ability ◽  
Fixed Bed Column ◽  
Linear And Nonlinear

The effect of bed depth on adsorption ability of natural zeolite to removal methylene blue (MB) from aqueous solution in the fixed-bed column was studied. The results showed that the increase in column height favored the MB removal form solution. The equilibrium uptake of MB onto unit mass zeolite increased with the bed depth growth. The experimental data were fitted to Yan model using linear and nonlinear regression analysis, respectively. The experimental points and the predicted curves using the Yan model were compared and the error analysis was performed. The results indicated that Yan model were good to predict the breakthrough curves and both two methods can be used to obtain the parameters of Yan model and to predict the breakthrough curves.

scholarly journals Simulated Biosorption of Cd(II) and Cu(II) in Single and Binary Metal Systems by Water Hyacinth (Eichhornia crassipes) using Aspen Adsorption

2017 ◽  
Vol 16 (2) ◽  
pp. 21 ◽  
Author(s):  
Adonis P. Adornado ◽  
Allan N. Soriano ◽  
Omar Nassif Orfiana ◽  
Mark Brandon J. Pangon ◽  
Aileen D. Nieva
Keyword(s):  
Heavy Metal ◽  
Water Hyacinth ◽  
Eichhornia Crassipes ◽  
Metal Uptake ◽  
Process Analysis ◽  
Fixed Bed ◽  
Breakthrough Curves ◽  
Competitive Sorption ◽  
Metal System ◽  
Binary Metal

Biosorption is becoming an attractive alternative for the removal of heavy metal from contaminated wastewaters since it offers low capital and operating costs. It has a great potential on heavy metal decontamination and the possibility of metal recovery. The study evaluated the performance of water hyacinth (Eichhornia crassipes) in a fixed bed column on sequestering heavy metals present in wastewaters. Column breakthrough curves at varying parameters were evaluated. The study used Aspen Adsorption® to simulate the biosorption process. Analysis of breakthrough curves for the single metal system shows that increasing both influent flow rate and initial metal concentration reduces the metal uptake of the column, while increasing bed height enhances the metal uptake of the column. Presence of both Cd(II) and Cu(II) in the system promotes competitive sorption processes. Analysis of the breakthrough curves for the binary metal system showed that copper ions adsorbed to the adsorbent are replaced by cadmium ions when the maximum capacity of the column is reached. This leads to the outlet concentration of Cu(II) exceeding its initial concentration. This phenomenon shows that Cd(II) has more affinity with E. crassipes than Cu(II).

Sign in / Sign up

Export Citation Format

Share Document