Adsorption Kinetics of Dibenzofuran in Activated Carbon Packed Bed

doi:10.1016/S1004-9541(08)60063-4

Chinese Journal of Chemical Engineering

Volume 16, Issue 2, April 2008, Pages 203-208

https://doi.org/10.1016/S1004-9541(08)60063-4 Get rights and content

Abstract

The adsorption of dibenzofuran (DBF) on three commercial granular activated carbons (GAC) was investigated to correlate the adsorption equilibrium and kinetics with the morphological characteristics of activated carbons. Breakthrough experiment was conducted to determine the isotherm and kinetics of dibenzofuran on the activated carbons. All the experiment runs were performed in a fixed bed with a process temperature of 368 K. The effects of adsorbent morphological properties on the kinetics of the adsorption process were studied. The equilibrium data are found satisfactory fitted to the Langmuir isotherm. An intraparticle diffusion model based on the obtained Langmuir isotherm was developed for predicting the fixed bed adsorption of dibenzofuran. The result indicated that this model fit all the breakthrough curves well. The surface diffusion coefficients of dibenzofuran on the activated carbon are calculated, and a relationship with the microporosity is found. As it was expected, the dibenzofuran molecule finds more kinetic restrictions for the diffusion in those carbons with narrower pore diameter.

References (22)

K. Liu et al.
“Polycyclic aromatic hydrocarbon (PAH) emissions from a coal-fired pilot FBC system”
J. Hazard. Mater.
(2001)
H. Nollet et al.
“Removal of PCBs from wastewater using fly ash”
Chemosphere
(2003)
G. McKay
“Dioxin characterization, formation and minimization during municipal solid waste incineration: Review”
Chem. Eng. J.
(2002)
J.S. Dusenbury et al.
“Advanced oxidant reactivity pertaining to granular activated carbon beds for air pollution control”
Carbon
(1996)
L. Luo et al.
“Adsorption and electrothermal desorption of organic vapors using activated carbon adsorbents with novel morphologies”
Carbon
(2006)
A.M. Mastral et al.
“Sorbent characteristics influence on the adsorption of PAC: I. PAH adsorption with the same number of rings”
Fuel Process. Technol.
(2002)
N. Wakao et al.
“Effect of fluid dispersion coefficients on particle-to-fluid mass transfer coefficients in packed beds: correlation of Sherwood numbers”
Chem. Eng. Sci.
(1978)
R. Murillo et al.
“Adsorption of phenanthrene on activated carbons: Breakthrough curve modeling”
Carbon
(2004)
P. Foley et al.
“An investigation of the adsorption of C₅-C₁₂ hydrocarbons in the ppmv and ppbv ranges on carbotrap B”
Environ. Sci. Technol.
(2001)
W.A. McClenny et al.
“Ambient level volatile organic compound (VOC) monitoring using solid adsorbents—Recent US EPA studies”
J. Environ. Monit.
(2002)

F.T. Matthew et al.

“The role of surface acidity and pore size distribution in the adsorption of 2-methylisoborneol via powdered activated carbon”

Carbon

(2007)

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It has been reported that the pore volume of ACs is a crucial factor in the adsorption of dioxins, and ACs with more mesopores could perform high removal efficiency of dioxins[18,19]. However, some researchers have drawn different conclusions and considered that the equilibrium adsorption capacity and diffusion coefficient of dioxins on ACs were controlled by the total surface area, and the micropores played a role of key significance in the adsorption process[20,21]. It is also reported that micropores were favorable to the adsorption of polychlorinated biphenyls (PCBs), and mesopore was key to adsorption rate[22,23].
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Mathematical models are necessary to gain insight into the operation of chemical process equipment to enhance its efficiency. Several mathematical models have been previously reported in the literature for fixed-bed adsorption (Aribike & Olafadehan, 2008; Başağaoğlu & McCoy, 2001; Başağaoğlu, Ginn, McCoy, & Mariño, 2000; Cheng, Jiang, Zhang, & Liu, 2004; Glueckauf & Coates, 1947; Jusoh, Noor, & Plow, 2002; Kuboňová, Obalová, Vlach, Troppová, & Kalousek, 2011; Li, Li, & Luo, 2008; Liaw, Wang, Greenkorn, & Chao, 1979; Nematollahzadeh, Abdekhodaie, & Shojaei, 2012; Patel, 2019; Shafeeyan, Wan Daud, & Shamiri, 2014; Shim, Lee, & Moon, 2003; Sircar & Hufton, 2000; Sircar, 1983; Sze, Lee, & McKay, 2008; Uguina, Sotelo, Delgado, Gómez, & Celemín, 2005; Valsaraj & Thibodeaux, 1999; Walker & Weatherley, 1997; Wood, Chakraborty, Smith, & Summers, 2019; Yang, 1992; Zhang & Cheng, 2000). Models describe the dynamics of the adsorption systems while incorporating the kinetics of different transport phenomena and adsorption isotherms at equilibrium conditions (Li et al., 2008).
Trichloroethylene (TCE) is largely used in industries as a cleaning and degreasing solvent. TCE is a potential carcinogen and is known to cause organ damage when exposed to prolonged higher concentrations. Numerical simulation of fixed and fluidized bed adsorption of TCE can help in the development of efficient adsorption processes to prevent industrial workers in the vicinity from acute TCE exposure. In the present work, a parametric optimization based numerical experimentation algorithm is implemented by open-source computational solvers to model fixed and fluidized bed adsorption of trichloroethylene vapors on activated carbon. The algorithm optimizes four parameters pertaining to linear driving force (LDF) formulation of surface barrier and microporous diffusion. The optimized parameters were utilized to evaluate $\bar{ζ}$ , a dimensionless number defined as the temporal and spatial average ratio of surface barrier diffusion resistance to microporous diffusion resistance. The average value of $\bar{ζ}$ is 0.139 for fixed bed operation (u/u_mf = 0.7), 1.130 for fluidized bed operation (u/u_mf = 1), 4.436 for fluidized bed operation (u/u_mf = 1.5) and 6.317 for fluidized bed operation (u/u_mf = 2). Therefore, the dimensionless number $\bar{ζ}$ may serve to predict the extent of change in amount adsorbed per unit adsorbent mass with change in fluidization velocity.
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Dibenzofuran has a similar molecule structure with dioxins and it is also less toxic as a common dechlorinated precursor of PCDD/Fs. Li et al. [18] investigated the adsorption of dibenzofuran on activated carbons in N2 atmosphere, and concluded that the diffusion of dibenzofuran molecule were restricted kinetically in carbons with narrower pore diameter. Some researcher studied the oxidative mechanisms of destruction of PCDD/Fs by using dibenzofuran moiety as model compound, and possible destruction pathways were proposed in different conditions using density functional theory [19,20].
Activated cokes integrated removal technologies have been widely used to abate polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) in sintering flue gas. A series of comparative adsorption experiments were performed by using nitric acid (HNO₃) treated activated coke with dibenzofuran as model pollutants. The physicochemical properties of activated cokes were analyzed by using various characterization methods. Combined with the results of experiments, the interactions of typical oxygenated groups with dibenzofuran were also calculated by density functional theory to reveal the nature relationships among the textural properties, oxygenated functional groups and dibenzofuran adsorption behaviors. It was demonstrated through adsorption experiments that adsorption capacity decreased with the enhanced oxidation degrees of activated cokes. Especially the adsorption capacities of activated cokes were probably deteriorated by the hydrophilic carboxyl and anhydride groups. In contrast, a higher adsorption rate was obtained with the increasing oxidation degrees. It was revealed through the density functional theory analysis that physical adsorption dominated the adsorption of dibenzofuran on activated cokes, and dibenzofuran was adsorbed preferentially on the activated cokes with oxygenated groups. Moreover, the formation of oxygenated groups increased the adsorption energy of dibenzofuran on activated cokes and accelerated the adsorption process. However, the enhanced competitive adsorption of oxygen (O₂) also led to the reduction of adsorption capacity for dibenzofuran. This study not only gives a sophisticated understanding for the relationship between surface oxygenated groups and dioxins adsorption abatement but also offers referential guidance for the design of carbonaceous adsorbent suitable for the adsorption of PCDD/Fs.
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2016, Chemosphere
Citation Excerpt :
Others preferred to use model compounds (e.g., chlorobenzenes or non-chlorinated dibenzofuran) instead of real dioxins to study adsorption isotherms. ( Li et al., 2005a, 2008) applied non-chlorinated dibenzofuran vapor as substitute for dioxins to conduct dynamic adsorption tests on a fixed-bed of activated carbon. Results showed that the adsorption data fitted a Langmuir equation relationship.
Activated carbon is widely used to abate dioxins and dioxin-like compounds from flue gas. Comparing commercial samples regarding their potential to adsorb dioxins may proceed by using test columns, yet it takes many measurements to characterise the retention and breakthrough of dioxins. In this study, commercial activated carbon samples are evaluated during tests to remove trace amounts of dioxins dissolved in n-hexane. The solution was prepared from fly ash collected from a municipal solid waste incinerator. The key variables selected were the concentration of dioxins in n-hexane and the dosage of activated carbon. Both polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) showed very high removal efficiencies (94.7%–98.0% for PCDDs and 99.7%–99.8% for PCDFs). The presence of a large excess of n-hexane solvent had little effect on the removal efficiency of PCDD/Fs. The adsorbed PCDD/Fs showed a linear correlation (R² > 0.98) with the initial concentrations. Comparative analysis of adsorption isotherms showed that a linear Henry isotherm fitted better the experimental data (R² = 0.99 both for PCDDs and PCDFs) than the more usual Freundlich isotherm (R² = 0.88 for PCDDs and 0.77 for PCDFs). Finally, the results of fingerprint analysis indicated that dioxin fingerprint (weight proportion of different congeners) on activated carbon after adsorption did not change from that in hexane.
Catalytic hydrodeoxygenation of 2-methoxy phenol and dibenzofuran over Pt/mesoporous zeolites
2015, Energy
The hydrodeoxygenation of 2-methoxy phenol and dibenzofuran, which are representative model compounds of bio-oil, was performed using two different Pt/mesoporous zeolite catalysts, Pt/mesoporous Y and Pt/mesoporous MFI. The reforming of 2-methoxy phenol and dibenzofuran via catalytic hydrodeoxygenation was investigated using a batch reactor at 40 bar and 250 °C. The characteristics of the catalysts were analyzed by N₂ adsorption-desorption, X-ray diffraction, and NH₃ temperature programmed desorption. Pt/mesoporous zeolite catalysts containing both strong acid sites and mesopores showed the higher conversion of 2-methoxy phenol than Pt/SiO₂ and Pt/Si-MCM-48 with no acid sites, Pt/γ-Al₂O₃, and a mixture of mesoporous Y and Pt/SiO₂, indicating the importance of both Pt and strong acid sites for high catalytic activity. Among the two Pt/mesoporous zeolite catalysts tested, the conversion of 2-methoxy phenol to cyclohexane over Pt/mesoporous Y was much higher than that over the Pt/mesoporous MFI. This was attributed to the better textural properties, such as surface area, pore volume and micropore size, compared to those of Pt/mesoporous MFI. The catalytic conversions of dibenzofuran obtained using two Pt/mesoporous zeolite catalysts were similar and the main products were 1,1′-bicyclohexyl, cyclopentylmethyl-cyclohexane and cyclohexane. In addition, the reaction mechanisms of 2-methoxy phenol and dibenzofuran over Pt/mesoporous zeolite were suggested.

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^*: Supported by the National Natural Science Foundation of China (29936100) and the Natural Science Foundation of Guangdong Province (7010327).

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Adsorption Kinetics of Dibenzofuran in Activated Carbon Packed Bed*

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