The Removal of 2-Chloroethyl Ethyl Sulfide ... - ACS Publications

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The Removal of 2-Chloroethyl Ethyl Sulfide Using Activated Carbon Nanofibers Embedded with MgO and Al2O3 Nanoparticles Saeed Dadvar,† Hossein Tavanai,*,† Mohammad Morshed,† and Mehran Ghiaci‡ †

Department of Textile Engineering, Center of Excellence in Applied Nanotechnology, Isfahan University of Technology, Isfahan, 84156-83111, Iran ‡ Department of Chemistry, Isfahan University of Technology, Isfahan, 84156-83111, Iran ABSTRACT: The 2-chloroethyl ethyl sulfide (2-CEES) decontamination ability of MgO and Al2O3 nanoparticles embedded in activated carbon nanofibers is investigated. It was found that higher amounts of embedded metal oxide nanoparticles lead to higher decontamination of 2-CEES. Moreover, decontamination of 2-CEES increases with higher specific surface area of the embedded metal oxide nanoparticles. Fourier transform infrared studies showed that MgO and Al2O3 nanoparticles embedded in activated carbon nanofibers adsorb and destroy 2-CEES through the formation of covalent/alkoxide bonds between 2-CEES and the surface reactive oxide/hydroxyl groups of metal oxide nanoparticles. It was also found that the weight loss and cross sectional shrinkage of the nanofibers, occurring during activation at elevated temperatures, is affected by the specific surface area and amount of embedded MgO and Al2O3 nanoparticles.

1. INTRODUCTION The detoxification of toxic gases is of considerable interest.1 Several gases such as mustard and nerve agents are noted as among the most important hazardous chemicals as they are highly toxic and persistent.2,3 Mustard toxicant (a blistering agent) is notorious as it causes serious hazards and can be lethal in high concentrations. Generally, mustard agent irreversibly alkylates key amines in organisms such as peptides, proteins, DNA, and membrane components, causing cell breakdown and death.4 Previously, permeable adsorptive protective garments containing granular activated carbon have been used as a means of protecting individuals against toxic chemicals of aerosol or vapor type in the contaminated atmosphere. In spite of relative effectiveness in protection, this kind of protective clothing can only absorb the gases physically, and therefore there is always a problem with handling and disposal of the used protective clothing to prevent any further contamination through desorption.5,6 It has been shown that some nanoparticles, particularly metal oxides such as TiO2,7 CaO,8 MgO,9 and Al2O310 with characteristics like high specific surface area and, as a result, enhanced chemical reactivity, can irreversibly break up mustard agent or its surrogates like 2-chloroethyl ethyl sulfide (2-CEES), into a benign byproduct at room temperature. Surface reactive oxide/hydroxyl groups of the above-mentioned oxides play the role of destructively adsorbing and detoxifying toxic chemicals.7−10 It is worth mentioning that, because mustard agent is extremely toxic and its use is restricted in secure laboratories, research on its © 2012 American Chemical Society

absorption is often conducted using surrogate compounds such as 2-CEES. 2-CEES is a liquid at room temperature and mimics the relevant physiochemical characteristics of mustard gas without any toxicity.11 To employ metal oxide nanoparticles as destructive adsorbents in protective clothing, a suitable substrate is needed to contain them. Impregnation of granular activated carbon with metal oxides is an example. However, heavy weight and discomfort for the wearer are major disadvantages of such protective clothing.5,6 Nanofibers with a high specific surface area have the potential to be incorporated with reactive chemicals,6,12 but due to the trapping of the nanoparticles inside polymeric substrates, the destructive adsorption efficiency of metal oxide nanoparticles embedded in nanofibers is much less than the metal oxide nanoparticles in their original powder form. Sundarrajan and Ramakrishna5 showed that the amount of paraoxon (a nerve agent simulant) hydrolyzed by polysulfone nanofibers containing MgO nanoparticles is 60 % less than MgO nanoparticle powder on their own. Mosaddeghirad13 found that the 2-CEES destructive adsorption of Al2O3 whiskers decreases when incorporated into polyamide nanofibers due to decreased exposure. Increasing the exposure of metal oxide nanoparticles embedded in polymeric substrates can improve their effectiveness against Received: December 14, 2011 Accepted: March 27, 2012 Published: April 5, 2012 1456

dx.doi.org/10.1021/je201328s | J. Chem. Eng. Data 2012, 57, 1456−1462

Journal of Chemical & Engineering Data

Article

20 h at room temperature. This was followed by sonication to achieve the maximum dispersion. To produce the composite PAN nanofibrous mat, the sonicated solutions were electrospun (voltage = 12 kV, nozzle-collector distance = 15 cm, feed rate = 0.16 mL·h−1). It must be pointed out that concentrations higher than (0.15, 0.20, and 0.18) mass fraction of MgO, Al2O3, and PAN powder, respectively, were not electrospinnable. Also it was observed that the mass fraction of PAN powder lower than 0.18 mass fraction resulted in the formation of beads on composite electrospun PAN nanofibers. The stabilization, carbonization, and activation of the abovementioned electrospun nanofibrous mats were carried out in a horizontal tube furnace with an internal diameter of 5 cm (ATBIN Co., Iran). During the stabilization phase, the samples were heated to 280 °C at a rate of 1 °C·min−1 under oxygen gas flow (50 mL·min−1) and kept at 280 °C for 2 h. After stabilization, carbonization was carried out by changing oxygen to nitrogen gas (100 mL·min−1) and raising the temperature at a rate of 2 °C·min−1 to 600 °C. The samples were kept at 600 °C for 2 h. To carry out the activation, the temperature was raised at a rate of 4 °C·min−1 to 800 °C under nitrogen gas flow (100 mL·min−1). The samples were heated at 800 °C for 1 h. In the end, the samples were allowed to cool down (below 50 °C) before being removed from the furnace. 2.3. Characterization. A scanning electron microscope (SEM) (LEO 1455VP, England) was employed to prepare the micrographs of the composite nanofibrous mats, from which the mean diameter of 100 nanofibers was measured by manual microstructure distance measurement (Nahamin Pardazan Asia Co., Iran) software. Relative weight loss of the samples due to stabilization, carbonization, and activation was calculated according to eq 1:

toxic chemicals. Activation is a convenient way to enhance the exposure of nanosized metal oxide particles embedded in nanofibers, such as polyacrylonitrile (PAN) or viscose rayon, as it mainly increases the specific surface area and total pore volume of the activated substrate. Studies have shown that the presence of nanoparticles, particularly metal oxides in the polymeric nanofibers like PAN, leads to enhanced activation.14−16 Kim and Lim17 prepared carbon nanofibers embedded with TiO2 nanoparticles and investigated their photocatalytic activity in the oxidation of gaseous acetaldehyde. They found that the activation is responsible for enhancing the adsorption capacity and photocatalytic degradation of gaseous acetaldehyde under UV irradiation. Oh et al.15 prepared PAN based activated carbon nanofibers embedded with manganese nanoparticles and studied their toluene physical adsorption ability. Their results showed that a higher specific surface area of nanoparticles and a bigger pore volume increase the adsorption of toluene. Nataraj et al.18 investigated the physical, thermal, and morphological characteristics of PAN based activated carbon nanofibers embedded with nickel nitrate. They found that the diameter of the activated carbon nanofibers decreases with increasing the nickel nitrate content which in turn leads to improvements in the porosity and specific surface area. As literature review showed very scarce information on the 2-CEES decontamination ability of activated carbon nanofibers embedded with MgO and Al2O3 nanoparticles, throwing some light on this subject constitutes the objective of the present study.

2. EXPERIMENTAL SECTION 2.1. Materials. Industrial PAN powder as the precursor and dimethylformamide (DMF) (Merck, Germany) as the solvent were used to electrospin PAN nanofibers embedded with metal oxides nanoparticles, namely, MgO, MgO Plus, Al2O3, and Al2O3 Plus purchased from NanoScale (USA). Some characteristics of these nanoparticles, as claimed by the producer, appear in Table 1.

⎛ W⎞ weight loss(%) = ⎜1 − f ⎟ · 100 Wi ⎠ ⎝

where Wi and Wf show the weight of nanofibrous mats before and after activation, respectively. To characterize the porosity of metal oxide free and embedded activated carbon nanofibrous mats, nitrogen adsorption isotherms (77 K) were obtained using adsorption/desorption porosimetry, BELSORP-mini II (Bell Instruments). Out-gassing to a residual vacuum of 5·10−6 mbar was carried out at 300 °C for 6 h. This technique provides invaluable information about the pore characteristics of adsorbents.19 The pore characteristics, that is, the specific surface area, total pore volume, and pore size distribution of metal oxide free as well as embedded activated carbon nanofibers, were obtained from nitrogen adsorption isotherms, according to the Brunauer−Emmett−Teller (BET) equation. In addition, the micropore volume was obtained according to the T-plot method.20 The T-plot shows the relationship between total pore volume and adsorption layer thickness. The intercept of the T-plot curve shows the micropore volume.10 The pore size distribution of the activated carbon nanofibers was obtained by the Horvath−Kawazoe method.21 2.4. 2-CEES Decontamination Ability of Composite Nanofibers. To evaluate the 2-CEES decontamination ability of the activated carbon nanofibers embedded with MgO and Al2O3 nanoparticles, gas chromatography (GC) (Agilent Technologies 6890N Network GC System) equipped with a flame ionization detector, a 60 m × 0.25 mm × 0.25 μm 19091 L-436 HP-50+ capillary column, injector (260 °C), detector (260 °C), and nitrogen flow gas (1.3 mL·min−1) was used. To

Table 1. Characteristics of Metal Oxide Nanoparticles commercial name NanoActive NanoActive NanoActive NanoActive

MgO MgO Plus Al2O3 Al2O3 Plus

crystal size

specific surface area

nm

m2·g−1

≤8 ≤4 amorphous amorphous

≥ ≥ ≥ ≥

(1)

230 600 275 550

As Table 1 shows, the specific surface area of the Plus grade of MgO and Al2O3 nanoparticles is 2.6 and 2 times higher than the normal grade, respectively. Cyclohexane as the solvent and xylene as the internal standard (used for destructive adsorption experiments) were purchased from Merck, Germany. 2-CEES (Sigma-Aldrich, USA) was employed as a mustard agent simulant. All reagents were used as received. 2.2. Preparation of PAN and Activated Carbon Nanofibers. Solutions of PAN in DMF containing (0.05, 0.10, and 0.15) mass fraction MgO and (0.10, 0.15, and 0.20) mass fraction Al2O3 nanoparticles (mass fraction relative to PAN weight) were prepared. Metal oxide nanoparticles were added to DMF first and mixed by a magnetic stirrer for 1 h at room temperature. Then, 0.18 mass fraction PAN (mass fraction relative to DMF weight) was added to DMF containing the nanoparticles and subsequently mixed by a magnetic stirrer for 1457



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perform the task of evaluating the 2-CEES decontamination ability, a reaction solution containing a mixture of 20 mL of cyclohexane as a solvent and 30 μL of 2-CEES was prepared and mixed on a shaker for 5 min. Before introducing the nanofiber samples, 1 mL of reaction solution was extracted as a control sample. Subsequently, an individual nanofibrous mat sample with a weight of about 9 mg was placed in a closed container containing the reaction solution and shaken again. After introducing the nanofiber sample, about 1 mL of reaction solution was extracted from the container at intervals of (0.5, 1, 2, 5, 10, 20, 30, 60, 120, and 240) min and added to 1 μL of xylene as the internal standard. This was then injected into GC. While injecting each sample, the GC column was maintained at 50 °C for 1 min. Then the temperature was raised to 125 °C (20 °C·min−1) and held for 2 min. In the end, the chromatogram was obtained for each sample, and the residual content of 2-CEES (amount of 2-CEES not adsorbed by the nanofiber sample) was measured. The subtraction of this residual content from the initial amount of 2-CEES gives the disappearance of 2-CEES which shows the decontamination ability. To identify the formation of any bonds between metal oxide nanoparticles embedded in activated carbon nanofibers and 2CEES, the nanofiber samples were removed from the reaction solution after 1 h, dried overnight at room temperature, and finally introduced to Fourier transform infrared spectroscopy (FTIR; Hartmann & Braun). Figure 1. SEM images of (a) metal oxide free PAN-NFs, (b) metal oxide free ACNFs, (c) PAN-NFs embedded with 0.10 mass fraction MgO Plus, and (d) PAN-NFs embedded with 0.10 mass fraction Al2O3 Plus, (e) ACNFs embedded with 0.10 mass fraction MgO Plus, and (f) ACNFs embedded with 0.10 mass fraction Al2O3 Plus (NFs = nanofibers; ACNFs = activated carbon nanofibers).

3. RESULTS AND DISCUSSION The surface morphology of metal oxide free PAN nanofibers before stabilization and metal oxide free activated carbon nanofibers as well as composite PAN nanofibers before stabilization and activated carbon nanofibers is depicted in Figures 1a−f. It is worth mentioning that, as Figure 1 shows, activation does not leave any defect or crack on the surface of fibers. However, it was observed that PAN nanofibers have the tendency to become soft and stick to each other as a result of the pyrolysis process. Figure 1 reveals that activation brings about a considerable amount of cross sectional shrinkage for the nanofibers. This effect is enhanced by the presence of metal oxide nanoparticles as observed from Table 2, which shows the average fiber diameter of activated carbon nanofibers embedded with MgO Plus and Al2O3 Plus. The initial diameter of metal oxide free PAN nanofibers before stabilization was about 748 nm. The decrease in the diameter of activated carbon nanofibers embedded with 0.10 mass fraction MgO Plus (256 nm) and Al2O3 Plus (277 nm) in comparison with metal oxide free ones (334 nm), as a result of activation, is related to the catalytic behavior of metal oxide nanoparticles at elevated temperatures (∼800 °C) which enhances the pyrolysis process.15,18 Table 3 shows the weight loss of PAN nanofibers embedded with MgO and Al2O3 nanoparticles after activation. The weight loss of metal oxide free PAN nanofibers after activation was about 54 %. As can be seen, generally, an increase in the amount of MgO and Al2O3 nanoparticles embedded in PAN nanofibers increases the weight loss of nanofibers as a result of activation. This can be related to the fact that increasing the amount of metal oxide nanoparticles leads to a higher catalytic activity and hence an enhancement of the pyrolysis process of the composite nanofibers during activation. It is worth mentioning that, during the pyrolysis of composite PAN nanofibers, considerable amounts of volatile compounds leave the nanofibers.14−16

Table 2. Mean Diameter of Activated Carbon Nanofibers Embedded with MgO Plus and Al2O3 Plus Nanoparticles nanoparticle amount type of nanoparticles MgO Plus

Al2O3 Plus

mean diameter

standard deviation

mass fraction

nm

nm

0.05 0.10 0.15 0.10 0.15 0.20

288 256 239 277 258 225

37.1 64.6 76.3 42.7 26.8 49.7

Table 3. Weight Loss of PAN Nanofibers Embedded with MgO and Al2O3 Nanoparticles after Activation specific surface area

weight loss (mass fraction)

type of nanoparticles

m2·g−1

0.05

0.10

0.15

0.20

MgO MgO Plus Al2O3 Al2O3 Plus

230 600 275 550

59 60

63 71 65 67

67 75 69 70

72 79

It is also interesting to note that, with increasing specific surface area of MgO and Al2O3 nanoparticles, the weight loss of PAN nanofibers embedded with the nanoparticles increases during activation. It is concluded that the weight loss of the embedded PAN nanofibers is enhanced with a higher specific surface of nanoparticles. The comparison of the weight loss of 1458



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PAN nanofibers embedded with 0.10 mass fraction and 0.15 mass fraction of MgO and Al2O3 nanoparticles shows a marginally lower value for MgO. The low-coordinated metal atoms in metal oxide nanoparticles are responsible for the catalytic activity which enhances the pyrolysis process. The catalytic activity of low-coordinated metal atoms in metal oxide nanoparticles such as MgO and Al2O3 has been explained in refs 15 and 22−24. The nitrogen adsorption isotherms of the activated carbon nanofibers embedded with MgO Plus and Al2O3 Plus nanoparticles are shown in Figure 2. As can be seen, the adsorption

Figure 3. Pore size distribution of activated carbon nanofibers (ACNFs) embedded with MgO Plus and Al2O3 Plus nanoparticles. ○, 0.15 mass fraction MgO Plus in ACNFs; □, 0.15 mass fraction Al2O3 Plus in ACNFs; △, 0.10 mass fraction MgO Plus in ACNFs; ◇, 0.10 mass fraction Al2O3 Plus in ACNFs; ∗, ACNFs.

Al2O3. Previous studies have shown that the formation of pore and pore channeling in the presence of metal oxide nanoparticles during activation can occur through physical phenomena such as the migration of metal oxide nanoparticles and catalytic activation during the pyrolysis process.15 Figure 4 shows the disappearance of 2-CEES for activated carbon nanofibers embedded with MgO, MgO Plus, Al2O3, and Al2O3 Plus nanoparticles. As can be seen, 2-CEES disappearance occurs with a high slope for up to 30 min and then slows down until finally reaching a stop after about 4 h. As can be seen from Figure 4, activation increases the 2-CEES decontamination ability of nanofibers embedded with 0.10 mass fraction MgO Plus and 0.10 mass fraction Al2O3 Plus nanoparticles by about 46 % after 1 h and by about 51 % and 47 % after 4 h in cyclohexane, respectively, due to the increased exposure of the nanoparticles to 2-CEES. A higher decontamination yield of 2-CEES with higher amounts of metal oxide nanoparticles is related to the increase in the number of nanoparticles as well as the increase in the available reactive sites of nanoparticles as a result of higher number of bigger pores. A comparison of the decontamination ability of the activated carbon nanofibers embedded with MgO Plus (600 m2·g−1) and Al2O3 Plus (550 m2·g−1) nanoparticles shows a better performance by MgO. Also, Al2O3 (275 m2·g−1) with a higher specific surface area shows a higher decontamination yield of 2-CEES (1 h in cyclohexane) than MgO with a lower specific surface (230 m2·g−1). This proves that a higher specific surface area of nanoparticles leads to a higher decontamination ability and highlights the role of nanotechnology in this field. These findings agree with the previous results obtained by Li et al.,25 who showed that the specific surface area of the metal oxide nanoparticles affects their chemical reactivity directly. Also, Lucas et al.26 reported that a higher specific surface area leads to higher accessibility of the surface reactive oxide/hydroxyl groups of the nanosized metal oxide particles. Considering the fact that MgO and Al2O3 nanoparticles which have been employed in this research did not have the same specific surface area, the results of this research cannot confirm the superiority of MgO over Al2O3. Martin et al.27 reached the conclusion that factors such as pore volume and pore size of the nanosized metal oxide particles affect their chemical reactivity.

Figure 2. Nitrogen adsorption isotherms of metal oxide free as well as MgO Plus and Al2O3 Plus nanoparticles embedded activated carbon nanofibers (ACNFs). ○, 0.15 mass fraction MgO Plus in ACNFs; □, 0.15 mass fraction Al2O3 Plus in ACNFs; △, 0.10 mass fraction MgO Plus in ACNFs; ◇, 0.10 mass fraction Al2O3 Plus in ACNFs; ∗, ACNFs.

of nitrogen is complete at a relatively low pressure (P/P0 < 0.1). Moreover, the nitrogen adsorption capacity of the activated samples increases with an increasing amount of MgO and Al2O3 nanoparticles. The initial slope of the adsorption isotherms increases with the same order as previously mentioned for the adsorption. Lower slopes show a wider distribution of pore size as seen in Figure 3. The comparison of the metal oxide free with metal oxide embedded samples in Figure 2 highlights the marked effect of metal oxide nanoparticles on the nitrogen adsorption of the activated samples. It is worth mentioning that the plateaus shown by the isotherms in Figure 2, also known as type I, indicate monolayer absorption. Moreover, the small slope increase at the end of isotherm graphs implies some mesopore characteristics. Figure 3 shows the pore size distribution of metal oxide free as well as activated carbon nanofibers embedded with MgO and Al2O3 nanoparticles (Horvath−Kawazoe method). As can be seen, a good proportion of the pore diameter of all of the samples is about or less than 2 nm. Figure 3 also shows that, with an increasing amount of metal oxide nanoparticles, the peak of the graphs shifts toward bigger pore sizes, that is, mesopores. Table 4 shows the pore characteristics of the activated carbon nanofibers embedded with MgO Plus and Al2O3 Plus obtained from BET. As can be seen, the specific surface area and total pore volume increase with an increasing amount of metal oxide nanoparticles, with MgO leading to a larger increase than 1459



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Table 4. Specific Surface Area, Total Pore Volume, Micropore Volume, Mesopore Volume, and Mesopore Proportion of Metal Oxide Free and Activated Carbon Nanofibers Embedded with MgO Plus and Al2O3 Plus Nanoparticles nanoparticle amount

specific surface area

total pore volume

micropore volume

mesopore volume

type of nanoparticles

mass fraction

m2·g−1

cm3·g−1

cm3·g−1

cm3·g−1

%

metal oxide free MgO Plus

0.00 0.10 0.15 0.10 0.15

383 838 1250 801 1103

0.20 0.60 1.00 0.55 0.95

0.09 0.49 0.90 0.43 0.86

0.11 0.11 0.09 0.12 0.09

55 18.5 9.3 22.1 9.7

Al2O3 Plus

mesopore proportion

Figure 4. Disappearance of 2-CEES for (a) MgO Plus, (b) MgO, (c) Al2O3 Plus, and (d) Al2O3 nanoparticles embedded ACNFs (NFs = nanofibers; ACNFs = activated carbon nanofibers). (a and b) ○, 0.15 mass fraction MgO Plus in ACNFs; □, 0.10 mass fraction MgO Plus in ACNFs; △, 0.05 mass fraction MgO Plus in ACNFs; ◇, 0.10 mass fraction MgO Plus in PAN-NFs; ×, ACNFs. (c and d) ○, 0.20 mass fraction Al2O3 in ACNFs; □, 0.15 mass fraction Al2O3 in ACNFs; △, 0.10 mass fraction Al2O3 in ACNFs; ◇, 0.10 mass fraction Al2O3 in PAN-NFs; ×, ACNFs.

covalent/alkoxide bonds between the surface reactive oxide/ hydroxyl groups of metal oxide nanoparticles and 2-CEES residual (1 h in cyclohexane).27,31 This can be considered as a proof of destructive adsorption of 2-CEES by MgO and Al2O3 nanoparticles embedded in activated carbon nanofibers. In other words, 2-CEES is effectively destroyed and detoxified on the surface of nanosized metal oxide particles. This agrees with the results obtained by Martin et al.27 and Narske et al.31 who suggested that 2-CEES is attracted by the hydrogen bonds formed between the sulfur of 2-CEES and the surface hydroxyl groups of metal oxides. It has also been suggested that, during 2-CEES decontamination, covalent bonding forms between the surface oxide groups of metal oxides and methylene groups of 2-CEES. According to literature,9,10,32 the benign byproducts are tightly held to the nanoparticles, and as a result, they cannot pollute the environment easily.

However, it has been reported that MgO nanoparticles with a larger amounts of surface reactive oxide/hydroxyl groups have a higher chemical reactivity than Al2O3 nanoparticles.26,28 Overall, the performance of the activated carbon nanofibers containing metal oxide nanoparticles shows that, in spite of high temperatures during activation, metal oxide nanoparticles have been able to decontaminate 2-CEES successfully. Therefore, it is concluded that the chemical reactivity of metal oxide nanoparticles through their surface reactive oxide/hydroxyl groups is preserved at high temperatures (∼800 °C) during activation. This is in accordance with studies already carried out, indicating that the nanosized metal oxide particles have a high thermal stability at elevated temperatures.29,30 Figure 5 shows the FTIR spectra of the embedded activated carbon nanofibers before and after decontamination of 2-CEES. The peak appearing at 1100 cm−1 shows the formation of 1460



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Figure 5. FTIR spectra of ACNFs embedded with 0.10 mass fraction (a) MgO and (b) Al2O3 nanoparticles before and after decontamination of 2-CEES after 1 h in cyclohexane (ACNFs = activated carbon nanofibers). Solid line, 0.10 mass fraction MgO (a) or Al2O3 (b) in ACNFs (after decontamination of 2-CEES); dotted line, 0.10 mass fraction MgO (a) or Al2O3 (b) in ACNFs (before decontamination of 2-CEES).

Notes

4. CONCLUSIONS

The authors declare no competing financial interest.

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This work showed that embedding MgO and Al2O3 nanoparticles in PAN nanofibers enhances the weight loss and cross sectional shrinkage during activation process. Similarly, the specific surface area and total pore volume increase with an increasing amount of metal oxide nanoparticles. When compared with Al2O3, MgO nanoparticles give rise to bigger pores. The decontamination yield of 2-CEES increases with increasing amount of metal oxide nanoparticles embedded in the activated carbon nanofibers. Furthermore, it was achieved that a higher specific surface area of nanosized metal oxide particles embedded in activated carbon nanofibers leads to a higher 2-CEES decontamination yield. FTIR studies showed that 2-CEES adsorbed by MgO and Al2O3 nanoparticles embedded in activated carbon nanofibers is destroyed through the formation of covalent/alkoxide bonds between the surface reactive oxide/hydroxyl groups of metal oxide nanoparticles and 2-CEES residual.

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AUTHOR INFORMATION

Corresponding Author

*Tel.: +98 311 3915030. Fax: +98 311 3912444. E-mail address: [email protected]. 1461



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