Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 56
Filter
Add more filters










Publication year range
1.
Sci Rep ; 14(1): 10548, 2024 May 08.
Article in English | MEDLINE | ID: mdl-38719844

ABSTRACT

This study not only provides an innovative technique for producing rigid polyurethane foam (RPUF) composites, but it also offers a way to reuse metallurgical solid waste. Rigid polyurethane (RPUF) composite samples have been prepared with different proportions of iron slag as additives, with a range of 0-25% mass by weight. The process of grinding iron slag microparticles into iron slag nanoparticles powder was accomplished with the use of a high-energy ball mill. The synthesized samples have been characterized using Fourier Transform Infrared Spectroscopy, and Scanning Electron Microscope. Then, their radiation shielding properties were measured by using A hyper-pure germanium detector using point sources 241Am, 133 BA, 152 EU, 137Cs, and 60Co, with an energy range of 0.059-1.408 MeV. Then using Fluka simulation code to validate the results in the energy range of photon energies of 0.0001-100 MeV. The linear attenuation coefficient, mass attenuation coefficient, mean free path, half-value layer and tenth-value layer, were calculated to determine the radiation shielding characteristics of the composite samples. The calculated values are in good agreement with the calculated values. The results of this study showed that the gamma-ray and neutron attenuation parameters of the studied polyurethane composite samples have improved. Moreover, the effect of iron slag not only increases the gamma-ray attenuation shielding properties but also enhances compressive strength and the thermal stability. Which encourages us to use polyurethane iron-slag composite foam in sandwich panel manufacturing as walls to provide protection from radiation and also heat insulation.

2.
Heliyon ; 10(3): e25065, 2024 Feb 15.
Article in English | MEDLINE | ID: mdl-38317972

ABSTRACT

In the recent past Metal-organic frameworks (MOFs) based thin films have demonstrated superior performance in various technological applications such as optical and optoelectronic devices, electrochemical energy storage, catalysis, and sensing. Herein we report tuning the optical performance of stable complexes using Cu and Fe metal ions with carboxylate benzene dicarboxylic (BDC), leading toward the formation of novel MOF structures. The formation of Cu-BDC and Fe-BDC were confirmed by XRD and SEM studies. The thermal stability of two MOFs was investigated, indicating that, the Cu-BDC is more stable than Fe-BDC. Further, the optical properties were investigated in the wavelength range 325-1100 nm, and the Fe-BDC exhibited greater optical transmission properties than Cu-BDC by 33 %, as investigated by Wemple-DiDomenico and Tauc models. The dispersion parameters related to optical studies for Cu-BDC were better in comparison to Fe-BDC, which could be attributed to the increase in Cu valence electrons due to an increase in the number of cations. The electrochemical behavior in terms of CV measurements shows the presence of pseudo capacitance in both Fe-BDC and Cu-BDC MOFs. The improved CV performance of Cu-BDC MOF suggests that it could be used as a storage material. This work successfully demonstrates the tailoring of optical properties related to MOF thin films through the formation of stable complexes using BDC as a potential material for the fabrication of OLED's and Solar cells. The improved CV performance suggests that these MOF based materials could be used as anodes in fabrication of batteries or supercapacitors.

3.
Int J Biol Macromol ; 255: 128081, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37977453

ABSTRACT

Contamination of various water resources with phosphate pollutant owing to the excessive use of phosphate fertilizers was labeled by dangerous consequences. Most of the water remediation methods are not efficient for phosphate recovery and always generate secondary wastes. Therefore, the current study is aimed to prepare a novel ecofriendly and sustainable APT500@CMC nanocomposite via simple covalent binding of thermally treated attapulgite clay at 500 °C (APT500) with carboxymethyl cellulose (CMC) using microwave irradiation process. The assembled nanocomposite was confirmed by diverse techniques. The optimum conditions for efficient 10, 25 and 50 mg/L PO43- removal were detected at pH 3, time 30 min, temperature 25 °C and mass 200 mg. The kinetic and isotherms were fitted both to a combination of pseudo 1st - 2nd orders and Langmuir model, while thermodynamic parameters verified PO43- removal via spontaneous and exothermic reaction behavior. The mode of interaction and binding of PO43- ions onto the surface of APT500@CMC were suggested via ion-pair interaction process. Excellent PO43- recovery (98.8 %) from real agricultural drainage wastewater was established. The explored APT500@CMC afforded good stability for five regeneration cycles. Therefore, the collected results confirm the validity of APT500@CMC for excellent removal of PO43- from real agricultural drainage wastewater.


Subject(s)
Nanocomposites , Water Pollutants, Chemical , Carboxymethylcellulose Sodium , Wastewater , Microwaves , Phosphates , Ions , Adsorption , Kinetics , Hydrogen-Ion Concentration
4.
Polymers (Basel) ; 15(22)2023 Nov 15.
Article in English | MEDLINE | ID: mdl-38006140

ABSTRACT

In this work, the effect of adding Pb nano/microparticles in polyurethane foams to improve thermo-physical and mechanical properties were investigated. Moreover, an attempt has been made to modify the micron-sized lead metal powder into nanostructured Pb powder using a high-energy ball mill. Two types of fillers were used, the first is Pb in micro scale and the second is Pb in nano scale. A lead/polyurethane nanocomposite is made using the in-situ polymerization process. The different characterization techniques describe the state of the dispersion of fillers in foam. The effects of these additions in the foam were evaluated, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD) have all been used to analyze the morphology and dispersion of lead in polyurethane. The findings demonstrate that lead is uniformly distributed throughout the polyurethane matrix. The compression test demonstrates that the inclusion of lead weakens the compression strength of the nanocomposites in comparison to that of pure polyurethane. The TGA study shows that the enhanced thermal stability is a result of the inclusion of fillers, especially nanofillers. The shielding efficiency has been studied, MAC, LAC, HVL, MFP and Zeff were determined either experimentally or by Monte Carlo calculations. The nuclear radiation shielding properties were simulated by the FLUKA code for the photon energy range of 0.0001-100 MeV.

5.
Int J Biol Macromol ; 253(Pt 1): 126489, 2023 Dec 31.
Article in English | MEDLINE | ID: mdl-37625740

ABSTRACT

Biodegradable polymers, biochars and metal organic frameworks (MOFs) have manifested as top prospects for elimination of harmful pollutants. In the current study, Ti-MOF was synthesized and decorated with TiO2 nanoparticles, then embedded into watermelon peel biochar and functionalized with chitosan hydrogel to produce Ti-MOF@TiO2@WMPB@CTH. Various instruments were employed to assure the effective production of the bionanocomposite. The HR-TEM and SEM studies referred to excellent surface porosity and homogeneity of Ti-MOF@TiO2@WMPB@CTH bionanocomposite, with 51.02-74.23 nm. Based on the BET analysis, the mesoporous structure has a significant surface area of 366.04 m2 g-1 and a considerable total pore volume of 11.38 × 10-2 cm3 g-1, with a mean pore size of 12.434 nm. Removal of doxorubicin (DOX) and hexavalent chromium (Cr(VI)) was examined under various experimentations. Pseudo-second order kinetic models in addition to Langmuir isotherm offered the best fitting. Thermodynamic experiments of the two contaminants demonstrated spontaneous and endothermic interactions. After five subsequent adsorption and desorption cycles, Ti-MOF@TiO2@WMPB@CTH bionanocomposite demonstrated an exceptional recyclability for the elimination of DOX and Cr(VI) ions, reaching 97.96 % and 95.28 %, respectively. Finally, the newly designed Ti-MOF@TiO2@WMPB@CTH bionanocomposite demonstrated a high removing efficiency of Cr(VI) ions and DOX from samples of real water.


Subject(s)
Chitosan , Water Pollutants, Chemical , Hydrogels , Chitosan/chemistry , Titanium/chemistry , Adsorption , Water Pollutants, Chemical/chemistry , Chromium/chemistry , Water/chemistry , Kinetics , Hydrogen-Ion Concentration
6.
Sci Rep ; 13(1): 5347, 2023 Apr 01.
Article in English | MEDLINE | ID: mdl-37005421

ABSTRACT

Most dye stuffs and coloring materials are mainly categorized as hazardous pollutants in water effluents due to their nature as non-biodegradable, highly toxic and extremely carcinogenic. For this reason, rapid and efficient eradication of waste dyes from wastewaters before discharging into water streams must be accomplished by an acceptable approach as adsorption technique. Therefore, the present study is aimed and devoted to synthesize a novel nanobiosorbent from three different constituents, gelatin (Gel) as a sustainable natural product, graphene oxide (GO) as an example of highly stable carbonaceous material and zirconium silicate (ZrSiO4) as an example of combined metal oxides for the formation of Gel@GO-F-ZrSiO4@Gel by using formaldehyde (F) as a cross-linkage reagent. Several characterization techniques as FT-IR were employed to identify the incorporated surface reactive Functionalities in Gel@GO-F-ZrSiO4@Gel as -OH, =NH, -NH2, -COOH and C=O, etc. The morphology for particle shape and size of Gel@GO-F-ZrSiO4@Gel were confirmed from the SEM and TEM analyses providing 15.75- 32.79 nm. The surface area was determined by the BET and found to correspond to 219.46 m2 g-1. Biosorptive removal of basic fuchsin (BF) pollutant as an example of a widely applicable dye in various activities was monitored and optimized under the influence of pH (2-10), reaction time (1-30 min), initial BF pollutant concentration (5-100 mg L-1), nanobiosorbent dosage (5-60 mg), temperature (30-60 °C) and interfering ions. The maximum biosorptive removal values of BF dye were established as 96.0 and 95.2% using 5 and 10 mg L-1, respectively at the recommended pH 7 condition. The Thermodynamic parameters demonstrated that the BF dye adsorption onto Gel@GO-F-ZrSiO4@Gel was taken place via spontaneous and endothermic reaction. Chemisorption is the predominant adsorption mechanism by forming multilayers upon nonhomogeneous surface in accordance with Freundlich model hypothesis. The applicability of the optimized Gel@GO-F-ZrSiO4@Gel in biosorptive removal of BF pollutant from real water sample was successfully accomplished by the batch technique. Thus, this study clearly shows that Gel@GO-F-ZrSiO4@Gel exhibited significant influences on remediation of industrial effluents containing BF pollutant with superior efficiency.

7.
Int J Biol Macromol ; 229: 344-353, 2023 Feb 28.
Article in English | MEDLINE | ID: mdl-36586656

ABSTRACT

A sustainable and efficient nanobentonite@sodium alginate@oleylamine (Nbent@Alg@OA) nanocomposite has been successfully synthesized via coating reaction of nanobentonite (Nbent) with alginate (Alg) and oleylamine (OA). The nanocomposite has been characterized and examined for the adsorption of 60Co(II) and 152+154Eu(III) radionuclides from simulated radioactive waste solution. FT-IR, XRD, SEM, and HR-TEM techniques have been applied to confirm the structural and morphological characteristics of the Nbent@Alg@OA nanocomposite. The effects of various parameters, such as pH of the medium, initial concentration of the radionuclides, contact time, and temperature on the adsorption of 60Co(II) and 152+154Eu(III) radionuclides were investigated by the batch adsorption technique. The results revealed that the optimum pH values for the adsorption of 152+154Eu (III) and 60Co (II) radionuclides were 4 and 5, respectively. The adsorption capacity of 152+154Eu(III) (65.6219 mg/g) was found greater than that of 60Co(II) (47.3469 mg/g). The adsorption process was found to be well described by the pseudo-second-order kinetic model. Furthermore, the equilibrium isotherm evaluation revealed that the Langmuir model was adequately matched with the adsorption data. According to the thermodynamic characteristics, the adsorption process was endothermic and spontaneous. Regeneration and reuse of Nbent@Alg@OA nanocomposite confirmed that the recycled nanocomposite was sufficiently efficient in several successive practical applications.


Subject(s)
Nanocomposites , Water Pollutants, Chemical , Spectroscopy, Fourier Transform Infrared , Adsorption , Alginates/chemistry , Cobalt Radioisotopes , Nanocomposites/chemistry , Water Pollutants, Chemical/chemistry , Hydrogen-Ion Concentration , Kinetics
8.
Int J Gynaecol Obstet ; 161(3): 760-768, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36572053

ABSTRACT

OBJECTIVE: To establish a prognostic model for endometrial cancer (EC) that individualizes a risk and management plan per patient and disease characteristics. METHODS: A multicenter retrospective study conducted in nine European gynecologic cancer centers. Women with confirmed EC between January 2008 to December 2015 were included. Demographics, disease characteristics, management, and follow-up information were collected. Cancer-specific survival (CSS) and disease-free survival (DFS) at 3 and 5 years comprise the primary outcomes of the study. Machine learning algorithms were applied to patient and disease characteristics. Model I: pretreatment model. Calculated probability was added to management variables (model II: treatment model), and the second calculated probability was added to perioperative and postoperative variables (model III). RESULTS: Of 1150 women, 1144 were eligible for 3-year survival analysis and 860 for 5-year survival analysis. Model I, II, and III accuracies of prediction of 5-year CSS were 84.88%/85.47% (in train and test sets), 85.47%/84.88%, and 87.35%/86.05%, respectively. Model I predicted 3-year CSS at an accuracy of 91.34%/87.02%. Accuracies of models I, II, and III in predicting 5-year DFS were 74.63%/76.72%, 77.03%/76.72%, and 80.61%/77.78%, respectively. CONCLUSION: The Endometrial Cancer Individualized Scoring System (ECISS) is a novel machine learning tool assessing patient-specific survival probability with high accuracy.


Subject(s)
Endometrial Neoplasms , Female , Humans , Retrospective Studies , Prognosis , Endometrial Neoplasms/diagnosis , Endometrial Neoplasms/therapy , Disease-Free Survival , Machine Learning
9.
Sci Rep ; 12(1): 19108, 2022 11 09.
Article in English | MEDLINE | ID: mdl-36351958

ABSTRACT

Metal-organic frameworks (MOFs) as porous materials have recently attracted research works in removal of toxic pollutants from water. Cr(VI) is well-known as one of the most toxic forms of chromium and the selection of efficient and effective Cr(VI)-remediation technology must be focused on a number of important parameters. Therefore, the objective of this work is to fabricate a novel nanohybrid adsorbent for removal of Cr(VI) by using assembled bimetallic MOFs (Fe0.75Cu0.25-BDC)-bound- Alginate-MoO3/Graphene oxide (Alg-MoO3/GO) via simple solvothermal process. The aimed Fe0.75Cu0.25-BDC@Alg-MoO3/GO nanohybrid was confirmed by FTIR, SEM, TEM, XRD and TGA. Adsorptive extraction of Cr(VI) from aqueous solution was aimed by various optimized experimental parameters providing optimum pH = 3, dosage = 5-10 mg, starting concentration of Cr(VI) = 5-15 mg L-1, shaking time = 5-10 min. The point of zero charge (pHPzc) was 3.8. For Cr(VI) removal by Fe0.75Cu0.25-BDC@Alg-MoO3/GO, four isotherm models were estimated: Langmuir, Freundlich, Temkin and Dubinin-Radushkevich (D-R) with calculated correlation coefficient (R2 = 0.9934) for Langmuir model which was higher than others. The collected results from the kinetic study clarified that pseudo-second order model is the most convenient one for describing the adsorption behavior of Cr(VI) and therefore, the adsorption process was suggested to rely on a chemisorption mechanism. Thermodynamic parameters referred that the adsorption mechanism is based on a spontaneous and exothermic process. Finally, the emerged Fe0.75Cu0.25-BDC@Alg-MoO3/GO nanohybrid was confirmed as an effective adsorbent for extraction of hexavalent chromium from real water specimens (tap, sea water and wastewater) with percentage recovery values > 98%.


Subject(s)
Metal-Organic Frameworks , Water Pollutants, Chemical , Water Purification , Adsorption , Water , Alginates , Water Pollutants, Chemical/analysis , Hydrogen-Ion Concentration , Chromium/analysis , Water Purification/methods , Kinetics
10.
Appl Radiat Isot ; 188: 110324, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35793582

ABSTRACT

A Promising nanocomposite from ß-Cyclodextrin/Alginate (ß-CD/Alg) composite impregnated with nickel oxide nanoparticles (NiO) has been synthesized and characterized using diverse techniques like FT-IR, XRD, TGA, and SEM. The new nanocomposite has been investigated for the efficient remediation of 51Cr and 56Mn radionuclides from simulated contaminated radioactive water. All the controlling experimental parameters such as solution pH, contact time, initial radionuclides concentration and adsorbent mass have been investigated and optimized. The distribution coefficient values Kd (mL/g) for 51Cr and/or 56Mn radionuclides have been calculated for all factors it was found that the optimum pH values were at 5 and 6 with Kd 5300, and 4500, for 51Cr and/or 56Mn, respectively and the equilibrium was at 90 and 100 (min) with Kd values 5600 and 4800 for 51Cr and/or 56Mn, respectively.


Subject(s)
Environmental Restoration and Remediation , Radioactive Pollutants , beta-Cyclodextrins , Adsorption , Alginates , Hydrogen-Ion Concentration , Kinetics , Nickel , Radioisotopes , Spectroscopy, Fourier Transform Infrared , Water Pollutants, Chemical/analysis , beta-Cyclodextrins/chemistry
11.
J Colloid Interface Sci ; 624: 602-618, 2022 Oct 15.
Article in English | MEDLINE | ID: mdl-35691228

ABSTRACT

Recent progress in nanotechnology via incorporation of small particle size as quantum dots (QDs) (1-10 nm) in many industrial activities and commercial products has led to significant undesired environmental impacts. Therefore, QDs removal from wastewater represents an interesting research topic with a lot of challenges for scientists and engineers nowadays. In this work, the coagulative removal of metal quantum dots as silver and gold from industrial water samples is explored. A novel biosorbent was assembled via binding of covalent organic frameworks (COFs) with magnetic zeolite and Arabic gum hydrogel (COFs@MagZ@AGH) as a promising removal material for Ag-QDs and Au-QDs. This was fully characterized by EDX, SEM, TEM, FT-IR, XPS, XRD and surface area and applied in coagulative removal of Au-QDs and Ag-QDs in presence of several experimental factors as pH, presence of other electrolytes, stirring time, initial QDs concentration, coagulant dosage, and temperature in order to optimize the removal processes. At optimum conditions, COFs@MagZ@AGH was able to recover 99.19% and 87.57% of Ag-QDs and Au-QDs QDs, respectively via chemical adsorption mechanism with perfect fitting to pseudo-second order model. Reuse of the recovered Ag/Au-QDs@COFs@MagZ@AGH as efficient catalysts in catalytic degradation of Rifampicin antibiotic (Rf) from water was additionally investigated and optimized via microwave-Fenton catalysts with excellent oxidative degradation efficiency (100%). Reusability and applicability of the biosorbent (COFs@MagZ@AGH) and catalysts (Ag/Au-QDs@COFs@MagZ@AGH) in real industrial water samples were also explored and successfully accomplished.


Subject(s)
Metal-Organic Frameworks , Quantum Dots , Zeolites , Adsorption , Anti-Bacterial Agents , Gold , Gum Arabic , Hydrogels , Metal-Organic Frameworks/chemistry , Microwaves , Oxidative Stress , Quantum Dots/chemistry , Rifampin , Silver , Spectroscopy, Fourier Transform Infrared , Water/chemistry
12.
J Colloid Interface Sci ; 606(Pt 2): 1597-1608, 2022 Jan 15.
Article in English | MEDLINE | ID: mdl-34500161

ABSTRACT

Recent industrial development and research progress in nanotechnology have led to the release of a number of nanomaterials with particle sizes (1-10 nm) which are categorized as quantum dots (QDs) in aquatic system. Disposal away of such QDs will cause potential pollution to the environment. Therefore, removal of disposed QDs from wastewater represents a challenging research subject for scientists and engineers. Hence, the objective of this study is devoted to assess the process of coagulative removal of silver quantum dots (Ag-QDs), as an example, from water by a novel super magnetic nanocomposite. Such material was aimed to prepare from the chemical combination and reaction of a generated Citrus sinensis and Citrus reticulata peels biochar (SMCsr-B) with spinel cobalt ferrite (CoFe2O4) as a super-magnetic source. The produced (SMCsr-B) was then crosslinked with polyurea-formaldehyde polymer (PUF) using EDA in only two minutes via microwave irradiation to produce (SMCsr-B/PUF). The SEM, EDX, FT-IR, XRD, and XPS analyses of the assembled (SMCsr-B/PUF) nanocomposite were acquired to confirm surface morphology and chemical structure. Controlling experimental factors were investigated as pH, time, and Ag-QDs pollutant concentration using microwave irradiative removal technique to establish the efficiency of coagulative adsorption of Ag-QDs onto (SMCsr-B/PUF). The solution (pH 5) was proved to exhibit the higher removal percentages of Ag-QDs in 15-25 s. SMCsr-B/PUF nanocomposite exhibited high removal efficiency as 93.12%, 92.39% and 92.48% upon using 20, 40 and 60 mg L-1 of Ag-QDs, respectively in presence of 10 mM NaCl. The kinetic and equilibrium adsorption data were best fitted to Freundlich model. The prepared SMCsr-B/PUF was successfully utilized as an efficient super magnetic nanocomposite for removal and recovery of Ag-QDs from aqueous environment.


Subject(s)
Nanocomposites , Quantum Dots , Adsorption , Charcoal , Magnetic Phenomena , Polymers , Silver , Spectroscopy, Fourier Transform Infrared
13.
Bioresour Technol ; 342: 126029, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34582985

ABSTRACT

An innovative magnetic nanocomposite was designed and fabricated by the functionalization and support of magnetic Mn-ferrite nanoparticle (MnFe2O4) with layered double hydroxide (Zn-Al LDHs) on cellulose and activated grapes stalks-derived biochar (AGB) (MnFe2O4@Zn-Al LDHs@Cel@AGB), to incorporate active functionalities and fantastic features with the aim to explore its feasibility for removal of harmful cationic species as methylene blue dye (MB) and mercury ions from wastewater. Structural, composition, morphological, surface area, adsorption performance of the fabricated nanocomposite toward both MB and Hg(II) and reusability were also investigated. The results referred that 10 mg ofthe nanocomposite exhibited 97.4% and 84.0 % removal efficiency of 10mgL-1 MB dye and 0.1 mol L-1 Hg(II) at 25 and 30 min contact times, respectively. Adsorption isotherms and kinetics of the two pollutants (MB and Hg(II)) were both governed by the pseudo-second-order equation with possible participation of intraparticle diffusion mechanism.


Subject(s)
Mercury , Nanocomposites , Nanoparticles , Water Pollutants, Chemical , Adsorption , Cellulose , Charcoal , Ferric Compounds , Hydroxides , Kinetics , Methylene Blue , Zinc
14.
Int J Biol Macromol ; 188: 879-891, 2021 Oct 01.
Article in English | MEDLINE | ID: mdl-34403678

ABSTRACT

Wastewaters is generally polluted with various inorganic and organic contaminants which require effective multipurpose purification technology. In this respect, a novel V2O5@Ch/Cu-TMA nanobiosorbent was constructed via encapsulation of nanoscale metal organic frameworks (Cu-TMA) into vanadium pentoxide-imbedded-chitosan matrix to comprehensively investigate its efficiency in removal of levofloxacin drug (LEVO) (e.g., organic pollutant) and chromium (VI) (e.g., inorganic pollutant) from water. Both LEVO drug and Cr(VI) adsorptions were correlated to pseudo-second order (R2 = 1) and Langmuir isotherm (R2 = 0.9924 for LEVO and R2 = 0.9815 for Cr(VI)). Adsorption of Cr(VI) was confirmed to be spontaneous and endothermic reactions, while LEVO was found to proceed via spontaneous and exothermic reactions based on the thermodynamic parameters. The emerged V2O5@Ch/Cu-TMA is regarded as an excellent nanobiosorbent for removal of inorganic contaminant as Cr(VI) from all natural water samples (tap, sea and wastewater) with percentages range 92.43%-96.95% and organic contaminant as LEVO drug from tap and wastewater (91.99%-97.20%).


Subject(s)
Chitosan/chemistry , Chromium/isolation & purification , Levofloxacin/isolation & purification , Metal-Organic Frameworks/chemistry , Nanoparticles/chemistry , Vanadium Compounds/chemistry , Water Pollutants, Chemical/isolation & purification , Adsorption , Electrolytes/chemistry , Hydrogen-Ion Concentration , Kinetics , Nanoparticles/ultrastructure , Osmolar Concentration , Porosity , Spectrometry, X-Ray Emission , Spectroscopy, Fourier Transform Infrared , Surface Properties , Temperature , Thermogravimetry , X-Ray Diffraction
15.
J Hazard Mater ; 408: 124951, 2021 04 15.
Article in English | MEDLINE | ID: mdl-33388629

ABSTRACT

In this work, a novel decorated and combined N-doped graphene oxide hydrogel with shrimp shell magnetic biochar (NGO3DH-MSSB) biosorbent was fabricated as an effective material for Cr(VI) removal. Three-dimensional self-assembled graphene oxide hydrogel was synthesized using nitrogen source, ethylenediamine (EDA). Characterizations of NGO3DH-MSSB biosorbent were established by FT-IR, TGA, SEM and BET, where high surface area (398.05 m2/g) compared with that of MSSB (138.64 m2/g) was characterized. The maximum achieved swelling ratio (800%) was only after 300 min. The binding mechanisms between Cr(VI) ions and NGO3DH-MSSB biosorbent were controlled by electrostatic adsorption (ion-pair), pore filling, and reduction-coordination reaction. Adsorption was described by the pseudo-second order kinetic (R2 =0.9994, 0.9983 and 0.9992) at 10, 50 and 100 mg/L and Langmuir isotherm model (R2 =0.9997, 0.9957 and 0.9912) at 25, 40 and 50 °C. The adsorption capacity (350.42 mg/g) was achieved at pH 1.0, using initial Cr(VI) concentration (100 mg/L) and contact time (180 min) at room temperature. NGO3DH-MSSB biosorbent could be successfully reused after eight cycles. The percentage removal of Cr(VI) were confirmed as 99.79%, 99.20% and 98.00% from tap water, sea water and wastewater, respectively.


Subject(s)
Hydrogels , Water Pollutants, Chemical , Adsorption , Charcoal , Chromium/analysis , Graphite , Hydrogen-Ion Concentration , Kinetics , Magnetic Phenomena , Spectroscopy, Fourier Transform Infrared , Water Pollutants, Chemical/analysis
16.
RSC Adv ; 11(24): 14829-14843, 2021 Apr 15.
Article in English | MEDLINE | ID: mdl-35424003

ABSTRACT

A novel magnetic starch-crosslinked-magnetic ethylenediamine nanocomposite, NFe3O4Starch-Glu-NFe3O4ED, was synthesized via microwave irradiation. The characteristics of the assembled NFe3O4Starch-Glu-NFe3O4ED nanocomposite were evaluated via XRD, FT-IR, TGA, BET, SEM and HR-TEM analyses. Its particle size was confirmed to be in the range 11.25-17.16 nm. The effectiveness of the designed nanocomposite for the removal of Cr(vi) ions was explored using the batch adsorption technique. Equilibrium results proved that the adsorptive removal of the target metal ions from aqueous solution was highly dependent on the optimized experimental parameters. The maximum adsorptive removal percentage values (%R) of Cr(vi) ions on NFe3O4Starch-Glu-NFe3O4ED obtained at pH 2.0 were 85.27%, 91.90%, and 96.47% using 10.0, 25.0, and 50.0 mg L-1 Cr(vi), respectively, for an equilibrium time of 30 min. The adsorption process was found to be strongly influenced by the presence of interfering salts including NaCl, CaCl2, KCl, MgCl2, and NH4Cl. Kinetic studies were performed and it was found that the pseudo-second and Elovich models well fitted the experimental data with the possible suggested ion-pair interaction mechanism. Different isotherm models were employed to assess the adsorption equilibrium, which was revealed by fitting Langmuir, Temkin and Freundlich models. The maximum uptake capacity based on the Langmuir model was 210.741 mg g-1. The effect of temperature and thermodynamics confirmed that adsorption was spontaneous, feasible, and endothermic in nature. Finally, the validity and applicability of using the NFe3O4Starch-Glu-NFe3O4ED nanocomposite to remove Cr(vi) ions from real water matrices were confirmed in the range of 91.2-94.7 ± 2.2-3.7%.

18.
Int J Biol Macromol ; 164: 920-931, 2020 Dec 01.
Article in English | MEDLINE | ID: mdl-32673717

ABSTRACT

The hydrogels-metal organic frameworks hybrid materials have received increasing attentions in recent years. The pectin hydrogel (PH) was derived from mandarin orange peels by-products and calcium chloride was applied as a cross-linker for incorporation with Fe-TAC metal organic frameworks (MOFs) for the formation of PHM composite on in situ synthesis method. The synthesized PHM composite was characterized by SEM, FT-IR, XRD and N2 adsorption-desorption and investigated for the adsorption of anionic species, Cr(VI) as well as cationic species, Pb(II) ions from aqueous solution. The adsorption kinetics for Cr(VI)/Pb(II) ions removal followed the pseudo-second order kinetic model and the equilibrium adsorption data were well fitted by Langmuir model. The maximum adsorption capacities of Cr(VI)/Pb(II) ions were 825.97 and 913.88 mg g-1, respectively. High swelling capacity (1500.0%) was also characterized for PHM composite after only 400 min and excellent stability for eight cycles with respect to regeneration with 0.1 mol L-1 HCl. The validity of PHM composite for simultaneous removal from real water matrices were confirmed as Cr(VI) (99.73, 99.87 and 99.87%) and Pb(II) (99.02, 98.55 and 98.55%) from tap water, sea water and industrial wastewater samples, respectively.


Subject(s)
Chromium/isolation & purification , Ions/isolation & purification , Lead/isolation & purification , Pectins/chemistry , Water Purification/methods , Adsorption , Biomass , Citrus/chemistry , Drinking Water , Fruit/chemistry , Hydrogels/chemistry , Hydrogen-Ion Concentration , Kinetics , Metal-Organic Frameworks , Seawater , Temperature , Thermodynamics , Wastewater , Water Pollutants, Chemical/isolation & purification
19.
Carbohydr Polym ; 245: 116438, 2020 Oct 01.
Article in English | MEDLINE | ID: mdl-32718595

ABSTRACT

Growing interests and efforts have been recently focused on design and assembly of novel hydrogel nanosorbents for removal of drugs from wastewater. Therefore, this work is aimed to immobilize and encapsulate starch hydrogel matrix onto metal organic frameworks (MOFs) and dope with nanomagnetite. The magnetic MOFs-Starch hydrogel (NFe3O4@Zn(GA)/Starch-Hydrogel) was synthesized via microwave irradiation process and characterized with high surface area (528.39 m2/g), mesoporous with pore size 2.90 nm and highly crystalline structure. The maximum swelling ratio (1000.0 %) was optimized at pH 10, 180 min and 25 °C. The validity of NFe3O4@Zn(GA)/Starch-Hydrogel for adsorptive removal of Fluvastatin statin drug provided maximum equilibrium adsorption capacity 782.05 mg g-1. The Langmuir isotherm and pseudo-second kinetics models were correlated well with the computed correlation coefficient values 0.9991 and 0.9997, respectively. The validity of NFe3O4@Zn(GA)/Starch-Hydrogel for removal of FLV statin drug from real water matrices was confirmed in the range 96.15-99.99 %.


Subject(s)
Anti-Bacterial Agents/chemistry , Fluvastatin/chemistry , Hydrogels/chemistry , Magnetite Nanoparticles/chemistry , Metal-Organic Frameworks/chemistry , Starch/chemistry , Wastewater/chemistry , Water Pollutants, Chemical/chemistry , Water Purification/methods , Adsorption , Capsules , Hydrogen-Ion Concentration , Kinetics , Microwaves , Porosity
20.
J Hazard Mater ; 397: 122770, 2020 Oct 05.
Article in English | MEDLINE | ID: mdl-32388094

ABSTRACT

Carbon quantum dots (CQDs) are a new class of carbon nanoparticles with superior advantages as small particle size, excellent biocompatibility and low toxicity which advance their recent applications in biotechnology, bioimaging and biosensing. The use of free CQDs in water treatment is greatly rendered by their high solubility in water. Therefore, this work is aimed to rapidly synthesize CQDs in only 10 min via microwave irradiation pyrolysis of starch-water system. The maximum fluorescence emission of CQDs was detected at 526 nm throughout the excitation wavelength (390 nm). The CQDs have been targeted to occupy the surface and pores of a polymeric material based on poly(anthranilic acid-formaldehyde-phthalic acid) (PAFP) to produce a novel CQDs@PAFP nanobiosorbent. The surface area of CQDs@PAFP was detected (28.79 m2 g-1 BET) and the nanoparticle size was confirmed (TEM). The highest removals of U(VI) by CQDs@PAFP nanobiosorbent were 95.5-98.0 % for 30-90 mg L-1. The sorption mechanism was designated to the pseudo-second-order model and closely tailored with Freundlich model. CQDs@PAFP was emerged as an excellent nanobiosorbent for U(VI) removal from wastewater (97.3 %) and sea water (96.0 %). CQDs@PAFP confirmed its excellent reusablity for efficient multi- recovery of U(VI) from different water samples.

SELECTION OF CITATIONS
SEARCH DETAIL
...