This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
In this study, the effects of the type and content of reactive diluents on the permeation/separat... more In this study, the effects of the type and content of reactive diluents on the permeation/separation of carbon dioxide/nitrogen (CO 2 /N 2) through acrylate-terminated polyurethane (APU)-acrylate/acrylic diluent (APUA) composite membranes was investigated. A series of APUs based on poly(ethylene glycol) (PEG)-1000 g mol −1 , toluene diisocyanate, and 2-hydroxyethyl methacrylate was synthesized and then diluted with several reactive diluents. The results obtained from differential scanning calorimetry (DSC) and Fourier transform infrared analyses showed that the microphase interference of hard and soft segments increased with increasing reactive diluent content. Furthermore, with increasing alkene double bond of reactive diluents, the degree of phase separation increased, which might be due to the higher gel content of APUAs. APUAs were used as top selective layer on PS/PSF as the support layer to obtain composite membrane. Field emission scanning electron microscopy micrographs revealed that APUAs penetrated into the support layer, leading to strong interfacial adhesion between APUA and support layers. The gas permeation experiments indicated that the gas permeability decreased, while the CO 2 /N 2 selectivity increased with increasing reactive diluent content due to the enhancement of crosslinking density of APUAs. Moreover, the reactive diluent with high polarity, for example, acrylonitrile monomer, exhibited higher CO 2 /N 2 selectivity due to the improvement in solubility of CO 2 in APUA, while the permeability was retained compared with other reactive diluents. The thickness of APUA selective layer exhibited expectedly opposite effect on permeability and selectivity; however, the increment in selectivity is higher than the reduction in permeability when the thickness decreased from 50 to 10 μm.
The current investigation was to present composite membranes with strong interfacial adhesion bet... more The current investigation was to present composite membranes with strong interfacial adhesion between top polymeric selective layer and the bottom micro-porous support layer with appropriate gas permeation behavior and practically suitable processing characteristics. To this end, a series of acrylate-terminated polyurethanes (APUs) based on poly(ethylene glycol) (PEG) with different molecular weights (Mn) of 600, 1000, 1500, 2000 and 4000 g/mol, toluene diisocyanate (TDI), and 2-hydroxyethyl methacrylate (HEMA) were synthesized. Composite membranes were prepared with UV-curable acrylate-terminated polyurethane/acrylate diluent (APUAs) as selective layer and polyester/polysulfone (PS/PSF) as support layer. FTIR-ATR and DSC analyses indicated that the micro-phase separation of soft and hard segments increased by increasing the
Journal of Inorganic and Organometallic Polymers and Materials, 2017
the particle size around 100 nm and uniform size distribution. The specific surface areas were ca... more the particle size around 100 nm and uniform size distribution. The specific surface areas were calculated using the Brunauer-Emmett-Teller method and surface area and total pore volume of NH 2-UiO-66 were calculated to be 1258 m 2 /g and 0.51 cm 3 /g, respectively. Methotrexate salt (MTX) was selected as the model drug which was adsorbed into inner pores and channels of MOFs by diffusion manner. The interaction between MOFs and MTX and the effect of pH on interaction between them in aqueous solution was investigated. The final results showed that UiO-66 have high adsorbing capacity and great affinity to MTX.
Journal of Environmental Chemical Engineering, 2018
A series of novel chitosan/nanodiamond (CTS/ND) composites containing NDs with variable surface c... more A series of novel chitosan/nanodiamond (CTS/ND) composites containing NDs with variable surface carboxyl groups and various concentrations were prepared using solution casting method. Powdery CTS/ND composites were employed as adsorbent of a model anionic dye (methyl orange, MO). Experimental results showed that the incorporation of NDs with high carboxylic content (ND-H) in to CTS increased substantially the maximum adsorption capacity of neat CTS from 167 mg/g to 454 mg/g. The remarkable adsorption capacity of dye on CTS/ND composites was associated to the oxygen-containing groups on the outer surface of NDs which would be beneficial to interact with the dye molecules through hydrogen bonding and electrostatic interactions. NDs with higher carboxylic content could improve the degree of dispersion in the CTS which in turn improved the accessible surface area of NDs and adsorption affinity of CTS/ND. The adsorption kinetics of CTS/ND adsorbent was well described by pseudo-second-order and Langmuir isotherm model showed very good fit with adsorption data.
In the current work, the performance of untreated nanodiamonds (UNDs) and thermally oxidized nano... more In the current work, the performance of untreated nanodiamonds (UNDs) and thermally oxidized nanodiamonds (ONDs), as adsorbents for selective adsorption of methylene blue (MB) and methyl orange (MO) from aqueous media, was examined. The adsorption isotherm, initial pH, ionic strength, and thermodynamic study were investigated in batch experiments. The equilibrium adsorption data were analyzed by Langmuir and Freundlich isotherm models, which indicated that the isotherms were well fitted with the Langmuir model for both dyes. Thermodynamic parameters indicated that the adsorption operation was a feasible, spontaneous, and physisorption process in experimental conditions. Meanwhile, the adsorption of MO onto the UND was exothermic and determined by enthalpy change, while the adsorption of MB onto the OND was endothermic and an entropy-controlling process. The adsorption selectivity study exhibited that OND can rapidly and selectively separate cationic MB dye from the MO and MB mixture. On the basis of the negatively charged surface of the OND with highly negative zeta potential, the fact that the OND opted to adsorb MB over MO was firmly dependent on the initial pH value and ionic strength, which suggested that the possible mechanism of adsorption such as electrostatic interaction, hydrogen bonding, and π−π stacking might be important. Finally, based on the mentioned considerations, thermally OND was an attractive candidate for rapid adsorption and separation of cationic dyes from aqueous solution.
We demonstrated a novel mixed matrix composite membrane (MMCM) based on acrylated polyurethane (A... more We demonstrated a novel mixed matrix composite membrane (MMCM) based on acrylated polyurethane (APU) and UiO-66 nanoparticles to separate CO 2 /N 2 mixture. UiO-66 and functionalized UiO-66 including NH 2-UiO-66 and GMA-UiO-66 were loaded in APU/HEMA (APUH) matrix at variable concentrations between 3-30 wt%. APUH/ GMA-UiO-66s MMCM exhibited strong adhesion with support layer of polyester/polysulfone (PS/PSF) which was not deteriorated after immersion in water for a long time (20 days). Incorporation of UiO-66 and its functionalized forms increased simultaneously permeability and CO 2 /N 2 selectivity which was indeed superior in comparison with MMCMs reported previously. GMA-UiO-66 filled MMCM displayed a CO 2 permeance of 14.5 Barrer and CO 2 /N 2 selectivity of 53 at critical concentration (25 wt%). This attractive separation performance of APUH/UiO-66 offered an exciting platform for development of composite membrane in sustainable CO 2 separations.
Metal organic frameworks (MOFs) UiO-66 (UiO stands for University of Oslo) and NH 2-UiO-66 were p... more Metal organic frameworks (MOFs) UiO-66 (UiO stands for University of Oslo) and NH 2-UiO-66 were prepared and characterized as sorbent (antidotal agents) for curcumin (CUR) adsorption. The structure of products were characterized by X-ray powder diffraction (XRD), Field emission scanning electron microscopy (FESEM), thermogravimetric analysis (TGA), Attenuated Total Reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), and N 2 adsorption-desorption measurements. FESEM showed NH 2-UiO-66 displayed symmetrical crystals with triangular base pyramid morphology, with the particle size around 100 nm and uniform size distribution. Adsorption capacities of CUR/MOFs with different mass ratios in the feed were investigated in the present study, and this investigation revealed that when the CUR/MOFs with mass ratio was around 0.4, the absorption capacity of NH 2-UiO-66 had tended to maximum. Although, functionalization reduced the specific surface area and free volume, introducing polar amine groups could improve the affinity of NH 2-UiO-66 respect to CUR. Kinetic studies showed that the kinetic data are well fitted with the pseudo-second-order model. MTT assay revealed that MOFs at the concentration range of 0-560 μg/ml had no cytotoxic effect on the Human Foreskin Fibroblast normal cell line (HFF-2). These results suggest that these MOFs could be safe as sorbent for adsorb CUR from the body.
Journal of Inorganic and Organometallic Polymers and Materials, 2018
In the present study the effect of nanodiamond (ND) on the adsorption capacity of Drug has been i... more In the present study the effect of nanodiamond (ND) on the adsorption capacity of Drug has been investigated. Thermal oxidation nanodiamond (OND) was used as adsorbents for Methotrexate adsorption. The surface properties of NDs were studied by Fourier transform infrared spectroscopy and zeta potential. It was determined that thermal oxidation changed the surface properties of ND, including increase the amount of carboxylic acid groups and decreasing the zeta potential of ND by increasing the thermal oxidation time. The adsorption experiments showed that untreated ND (UND) has large adsorption capacity and fast adsorption kinetic for methotrexate (MTX). These results suggest that the adsorption behavior of UND with the MTX follows not only the charge but also the chemical interaction. Due to form the strong hydrogen bond between the carboxyl groups of MTX and the oxygen containing groups on the surface of NDs, Kinetic studies showed that the kinetic data are well fitted with the pseudo-second-order model for most of the adsorbents. MTT assay, Hemolysis assay and acute toxicity were used for determining biocompatibility of the adsorbents; MTT assay showed no significant toxicity up to near 300 µg/mL, OND showed neglectable hemolysis and acute toxicity result demonstrated OND was nontoxic.
In the present study, capability of nanodiamond (ND) for the adsorption of anionic (methyl orange... more In the present study, capability of nanodiamond (ND) for the adsorption of anionic (methyl orange, MO) and cationic (methylene blue, MB) dyes from aqueous solution was investigated. Employing fourier transform infrared (FTIR) spectroscopy, Boehm titration method and zeta potential, it was found that the simple thermal oxidation of ND at 425°C, increased the content of carboxylic acid of ND and accordingly the zeta potential of ND decreased considerably. Therefore, a series of oxidized NDs (OND) at various oxidation times and as-received untreated ND (UND) was used as adsorbents of MO and MB. The adsorption experiments exhibited that UND had large adsorption capacity, very fast adsorption kinetics and excellent selectivity for MO over MB. These results suggested that
Industrial & Engineering Chemistry Research, 2018
Three versions of zirconium-based metal organic framework, NH 2-UiO-66, GMA-UiO-66 and EDA-UiO-66... more Three versions of zirconium-based metal organic framework, NH 2-UiO-66, GMA-UiO-66 and EDA-UiO-66, were synthesized and employed as adsorbent for CO 2 /CH 4 separation. GMA-UiO-66 was synthesized via ring opening reaction between the amine species in the framework and epoxy groups in glycidyl methacrylate (GMA), while the green aza-Michael addition reaction was used for the first time to functionalize GMA-UiO-66 with ethylenediamine (EDA). The products were characterized by BET, XRD, TGA, FESEM, ICP-OES, 1 H NMR, mass spectroscopy and FTIR-ATR methods to monitor their textural properties before and after functionalization. The results indicated that GMA was
A highly water stable metal-organic framework (MOF) based on zirconium, i.e. UiO-66, was synthesi... more A highly water stable metal-organic framework (MOF) based on zirconium, i.e. UiO-66, was synthesized and then employed to adsorptive removal of an anionic dye, methyl orange (MO), and a cationic dye, methylene blue (MB), from aqueous solution. In this work, for the first time, the long term stability of UiO-66 in water was investigated for 12 months. Xray diffraction (XRD), field emission scanning electron microscopy (FESEM) and N 2 adsorption/desorption analysis were employed to monitor the textural alteration of UiO-66 during water aging. The results indicated that the structure of UiO-66 was mostly retained and its adsorption capacity toward dyes exhibited minor loss after long term water aging. Experimental data showed that adsorption capacity of UiO-66 toward MO was higher than
A metal organic framework (MOF) modified with amino group (NH 2-UiO-66) was functionalized with g... more A metal organic framework (MOF) modified with amino group (NH 2-UiO-66) was functionalized with glycidyl methacrylate (GMA) via ring opening reaction between the amine species in the framework and epoxy groups in GMA. The products were characterized by X-ray powder diffraction (XRD), nuclear magnetic resonance (NMR) spectroscopy, field emission scanning electron microscopy (FESEM), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), inductively coupled plasma-optical emission spectrometry (ICP-OES), and N 2 adsorption-desorption measurements to monitor their textural properties before and after functionalization. The BET surface area, pore volume, and pore diameter of NH 2-UiO-66 were reduced after treatment with GMA. However, the crystalline structure, morphology, and thermal stability were retained. Single-gas adsorption isotherm measurements exhibited that CO 2 adsorption capacity of GMA-UiO-66 was enhanced comparatively due to the presence of many polar
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Enhancement of adsorption of heavy metals by functionalization with polar compounds. UiO-66-EDA w... more Enhancement of adsorption of heavy metals by functionalization with polar compounds. UiO-66-EDA was stable, which can be regenerated by simple washing. UiO-66-EDA exhibited high adsorption capacity (243.90 mg/g) for lead ions. The electron exchange, sharing, and covalent interactions are the main adsorption mechanisms.
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
In this study, the effects of the type and content of reactive diluents on the permeation/separat... more In this study, the effects of the type and content of reactive diluents on the permeation/separation of carbon dioxide/nitrogen (CO 2 /N 2) through acrylate-terminated polyurethane (APU)-acrylate/acrylic diluent (APUA) composite membranes was investigated. A series of APUs based on poly(ethylene glycol) (PEG)-1000 g mol −1 , toluene diisocyanate, and 2-hydroxyethyl methacrylate was synthesized and then diluted with several reactive diluents. The results obtained from differential scanning calorimetry (DSC) and Fourier transform infrared analyses showed that the microphase interference of hard and soft segments increased with increasing reactive diluent content. Furthermore, with increasing alkene double bond of reactive diluents, the degree of phase separation increased, which might be due to the higher gel content of APUAs. APUAs were used as top selective layer on PS/PSF as the support layer to obtain composite membrane. Field emission scanning electron microscopy micrographs revealed that APUAs penetrated into the support layer, leading to strong interfacial adhesion between APUA and support layers. The gas permeation experiments indicated that the gas permeability decreased, while the CO 2 /N 2 selectivity increased with increasing reactive diluent content due to the enhancement of crosslinking density of APUAs. Moreover, the reactive diluent with high polarity, for example, acrylonitrile monomer, exhibited higher CO 2 /N 2 selectivity due to the improvement in solubility of CO 2 in APUA, while the permeability was retained compared with other reactive diluents. The thickness of APUA selective layer exhibited expectedly opposite effect on permeability and selectivity; however, the increment in selectivity is higher than the reduction in permeability when the thickness decreased from 50 to 10 μm.
The current investigation was to present composite membranes with strong interfacial adhesion bet... more The current investigation was to present composite membranes with strong interfacial adhesion between top polymeric selective layer and the bottom micro-porous support layer with appropriate gas permeation behavior and practically suitable processing characteristics. To this end, a series of acrylate-terminated polyurethanes (APUs) based on poly(ethylene glycol) (PEG) with different molecular weights (Mn) of 600, 1000, 1500, 2000 and 4000 g/mol, toluene diisocyanate (TDI), and 2-hydroxyethyl methacrylate (HEMA) were synthesized. Composite membranes were prepared with UV-curable acrylate-terminated polyurethane/acrylate diluent (APUAs) as selective layer and polyester/polysulfone (PS/PSF) as support layer. FTIR-ATR and DSC analyses indicated that the micro-phase separation of soft and hard segments increased by increasing the
Journal of Inorganic and Organometallic Polymers and Materials, 2017
the particle size around 100 nm and uniform size distribution. The specific surface areas were ca... more the particle size around 100 nm and uniform size distribution. The specific surface areas were calculated using the Brunauer-Emmett-Teller method and surface area and total pore volume of NH 2-UiO-66 were calculated to be 1258 m 2 /g and 0.51 cm 3 /g, respectively. Methotrexate salt (MTX) was selected as the model drug which was adsorbed into inner pores and channels of MOFs by diffusion manner. The interaction between MOFs and MTX and the effect of pH on interaction between them in aqueous solution was investigated. The final results showed that UiO-66 have high adsorbing capacity and great affinity to MTX.
Journal of Environmental Chemical Engineering, 2018
A series of novel chitosan/nanodiamond (CTS/ND) composites containing NDs with variable surface c... more A series of novel chitosan/nanodiamond (CTS/ND) composites containing NDs with variable surface carboxyl groups and various concentrations were prepared using solution casting method. Powdery CTS/ND composites were employed as adsorbent of a model anionic dye (methyl orange, MO). Experimental results showed that the incorporation of NDs with high carboxylic content (ND-H) in to CTS increased substantially the maximum adsorption capacity of neat CTS from 167 mg/g to 454 mg/g. The remarkable adsorption capacity of dye on CTS/ND composites was associated to the oxygen-containing groups on the outer surface of NDs which would be beneficial to interact with the dye molecules through hydrogen bonding and electrostatic interactions. NDs with higher carboxylic content could improve the degree of dispersion in the CTS which in turn improved the accessible surface area of NDs and adsorption affinity of CTS/ND. The adsorption kinetics of CTS/ND adsorbent was well described by pseudo-second-order and Langmuir isotherm model showed very good fit with adsorption data.
In the current work, the performance of untreated nanodiamonds (UNDs) and thermally oxidized nano... more In the current work, the performance of untreated nanodiamonds (UNDs) and thermally oxidized nanodiamonds (ONDs), as adsorbents for selective adsorption of methylene blue (MB) and methyl orange (MO) from aqueous media, was examined. The adsorption isotherm, initial pH, ionic strength, and thermodynamic study were investigated in batch experiments. The equilibrium adsorption data were analyzed by Langmuir and Freundlich isotherm models, which indicated that the isotherms were well fitted with the Langmuir model for both dyes. Thermodynamic parameters indicated that the adsorption operation was a feasible, spontaneous, and physisorption process in experimental conditions. Meanwhile, the adsorption of MO onto the UND was exothermic and determined by enthalpy change, while the adsorption of MB onto the OND was endothermic and an entropy-controlling process. The adsorption selectivity study exhibited that OND can rapidly and selectively separate cationic MB dye from the MO and MB mixture. On the basis of the negatively charged surface of the OND with highly negative zeta potential, the fact that the OND opted to adsorb MB over MO was firmly dependent on the initial pH value and ionic strength, which suggested that the possible mechanism of adsorption such as electrostatic interaction, hydrogen bonding, and π−π stacking might be important. Finally, based on the mentioned considerations, thermally OND was an attractive candidate for rapid adsorption and separation of cationic dyes from aqueous solution.
We demonstrated a novel mixed matrix composite membrane (MMCM) based on acrylated polyurethane (A... more We demonstrated a novel mixed matrix composite membrane (MMCM) based on acrylated polyurethane (APU) and UiO-66 nanoparticles to separate CO 2 /N 2 mixture. UiO-66 and functionalized UiO-66 including NH 2-UiO-66 and GMA-UiO-66 were loaded in APU/HEMA (APUH) matrix at variable concentrations between 3-30 wt%. APUH/ GMA-UiO-66s MMCM exhibited strong adhesion with support layer of polyester/polysulfone (PS/PSF) which was not deteriorated after immersion in water for a long time (20 days). Incorporation of UiO-66 and its functionalized forms increased simultaneously permeability and CO 2 /N 2 selectivity which was indeed superior in comparison with MMCMs reported previously. GMA-UiO-66 filled MMCM displayed a CO 2 permeance of 14.5 Barrer and CO 2 /N 2 selectivity of 53 at critical concentration (25 wt%). This attractive separation performance of APUH/UiO-66 offered an exciting platform for development of composite membrane in sustainable CO 2 separations.
Metal organic frameworks (MOFs) UiO-66 (UiO stands for University of Oslo) and NH 2-UiO-66 were p... more Metal organic frameworks (MOFs) UiO-66 (UiO stands for University of Oslo) and NH 2-UiO-66 were prepared and characterized as sorbent (antidotal agents) for curcumin (CUR) adsorption. The structure of products were characterized by X-ray powder diffraction (XRD), Field emission scanning electron microscopy (FESEM), thermogravimetric analysis (TGA), Attenuated Total Reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), and N 2 adsorption-desorption measurements. FESEM showed NH 2-UiO-66 displayed symmetrical crystals with triangular base pyramid morphology, with the particle size around 100 nm and uniform size distribution. Adsorption capacities of CUR/MOFs with different mass ratios in the feed were investigated in the present study, and this investigation revealed that when the CUR/MOFs with mass ratio was around 0.4, the absorption capacity of NH 2-UiO-66 had tended to maximum. Although, functionalization reduced the specific surface area and free volume, introducing polar amine groups could improve the affinity of NH 2-UiO-66 respect to CUR. Kinetic studies showed that the kinetic data are well fitted with the pseudo-second-order model. MTT assay revealed that MOFs at the concentration range of 0-560 μg/ml had no cytotoxic effect on the Human Foreskin Fibroblast normal cell line (HFF-2). These results suggest that these MOFs could be safe as sorbent for adsorb CUR from the body.
Journal of Inorganic and Organometallic Polymers and Materials, 2018
In the present study the effect of nanodiamond (ND) on the adsorption capacity of Drug has been i... more In the present study the effect of nanodiamond (ND) on the adsorption capacity of Drug has been investigated. Thermal oxidation nanodiamond (OND) was used as adsorbents for Methotrexate adsorption. The surface properties of NDs were studied by Fourier transform infrared spectroscopy and zeta potential. It was determined that thermal oxidation changed the surface properties of ND, including increase the amount of carboxylic acid groups and decreasing the zeta potential of ND by increasing the thermal oxidation time. The adsorption experiments showed that untreated ND (UND) has large adsorption capacity and fast adsorption kinetic for methotrexate (MTX). These results suggest that the adsorption behavior of UND with the MTX follows not only the charge but also the chemical interaction. Due to form the strong hydrogen bond between the carboxyl groups of MTX and the oxygen containing groups on the surface of NDs, Kinetic studies showed that the kinetic data are well fitted with the pseudo-second-order model for most of the adsorbents. MTT assay, Hemolysis assay and acute toxicity were used for determining biocompatibility of the adsorbents; MTT assay showed no significant toxicity up to near 300 µg/mL, OND showed neglectable hemolysis and acute toxicity result demonstrated OND was nontoxic.
In the present study, capability of nanodiamond (ND) for the adsorption of anionic (methyl orange... more In the present study, capability of nanodiamond (ND) for the adsorption of anionic (methyl orange, MO) and cationic (methylene blue, MB) dyes from aqueous solution was investigated. Employing fourier transform infrared (FTIR) spectroscopy, Boehm titration method and zeta potential, it was found that the simple thermal oxidation of ND at 425°C, increased the content of carboxylic acid of ND and accordingly the zeta potential of ND decreased considerably. Therefore, a series of oxidized NDs (OND) at various oxidation times and as-received untreated ND (UND) was used as adsorbents of MO and MB. The adsorption experiments exhibited that UND had large adsorption capacity, very fast adsorption kinetics and excellent selectivity for MO over MB. These results suggested that
Industrial & Engineering Chemistry Research, 2018
Three versions of zirconium-based metal organic framework, NH 2-UiO-66, GMA-UiO-66 and EDA-UiO-66... more Three versions of zirconium-based metal organic framework, NH 2-UiO-66, GMA-UiO-66 and EDA-UiO-66, were synthesized and employed as adsorbent for CO 2 /CH 4 separation. GMA-UiO-66 was synthesized via ring opening reaction between the amine species in the framework and epoxy groups in glycidyl methacrylate (GMA), while the green aza-Michael addition reaction was used for the first time to functionalize GMA-UiO-66 with ethylenediamine (EDA). The products were characterized by BET, XRD, TGA, FESEM, ICP-OES, 1 H NMR, mass spectroscopy and FTIR-ATR methods to monitor their textural properties before and after functionalization. The results indicated that GMA was
A highly water stable metal-organic framework (MOF) based on zirconium, i.e. UiO-66, was synthesi... more A highly water stable metal-organic framework (MOF) based on zirconium, i.e. UiO-66, was synthesized and then employed to adsorptive removal of an anionic dye, methyl orange (MO), and a cationic dye, methylene blue (MB), from aqueous solution. In this work, for the first time, the long term stability of UiO-66 in water was investigated for 12 months. Xray diffraction (XRD), field emission scanning electron microscopy (FESEM) and N 2 adsorption/desorption analysis were employed to monitor the textural alteration of UiO-66 during water aging. The results indicated that the structure of UiO-66 was mostly retained and its adsorption capacity toward dyes exhibited minor loss after long term water aging. Experimental data showed that adsorption capacity of UiO-66 toward MO was higher than
A metal organic framework (MOF) modified with amino group (NH 2-UiO-66) was functionalized with g... more A metal organic framework (MOF) modified with amino group (NH 2-UiO-66) was functionalized with glycidyl methacrylate (GMA) via ring opening reaction between the amine species in the framework and epoxy groups in GMA. The products were characterized by X-ray powder diffraction (XRD), nuclear magnetic resonance (NMR) spectroscopy, field emission scanning electron microscopy (FESEM), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), inductively coupled plasma-optical emission spectrometry (ICP-OES), and N 2 adsorption-desorption measurements to monitor their textural properties before and after functionalization. The BET surface area, pore volume, and pore diameter of NH 2-UiO-66 were reduced after treatment with GMA. However, the crystalline structure, morphology, and thermal stability were retained. Single-gas adsorption isotherm measurements exhibited that CO 2 adsorption capacity of GMA-UiO-66 was enhanced comparatively due to the presence of many polar
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Enhancement of adsorption of heavy metals by functionalization with polar compounds. UiO-66-EDA w... more Enhancement of adsorption of heavy metals by functionalization with polar compounds. UiO-66-EDA was stable, which can be regenerated by simple washing. UiO-66-EDA exhibited high adsorption capacity (243.90 mg/g) for lead ions. The electron exchange, sharing, and covalent interactions are the main adsorption mechanisms.
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