Synthesis and Characterizations of Titanium Tungstophosphate Nanoparticles for Heavy Metal Ions Removal

2016 ◽  
Vol 257 ◽  
pp. 187-192 ◽  
Author(s):  
Mohamed Ali Ghanem ◽  
Nezar H. Khdary ◽  
Abdullah M. Almayouf ◽  
Mabrook A. Salah

Ionic exchange of multi-components titanium tungstophosphate nanoparticles (TiWP-NPs) were prepared using sol-gel reaction of titanium isoperoxide and tungestophosphoric acid (TPA) in presence of CTAB surfactant. The X-ray, BET and TEM characterizations showed that the nanoparticles exhibit the characteristic structure of titanium tungstophosphate and a BET surface area of 74 ± 3 m2/g was achieved. The TPA has shown an effect on the self-assembly process and maintains the TPA content to minimum would be beneficial for obtaining higher surface area of TiWP nanoparticles. Metal ions adsorption of Cu(II), Pb(II) or Cd(II) using the resulting titanium tungstophosphate nanparticles materials is investigated and up to 95% removal percentage was achieved. Using this method, nanoparticles of ionic exchange titanium tungstophosphate can be synthesized in the form of powder and amenable to mass production.

2018 ◽  
Vol 63 (1) ◽  
pp. 85-95 ◽  
Author(s):  
Harish Phattepur ◽  
Gowrishankar Bychapur Siddaiah ◽  
Nagaraju Ganganagappa

A sol-gel method was employed to synthesise pure titanium dioxide (TiO2) and surfactant assisted TiO2 nanoparticles (NPs). The effect of novel surfactant viz., Lauryl lactyl lactate on photocatalytic properties of TiO2 was studied. TiO2 NPs were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), UV-Vis Diffuse Reflectance spectra (DRS), Field emission scanning electron microscopy (FE-SEM), Transmission electron microscopy (TEM), Thermo gravimetric analysis (TGA), and Brunauer – Emmet - Teller (BET) surface area. Anatase phase of TiO2 was confirmed by X-Ray diffraction pattern and the crystallite size was between 9–19 nm. Addition of surfactant improved the BET surface area, surface defects, while the agglomeration of particles was reduced. DRS results revealed that the addition of surfactant to TiO2 sol induced a red shift of the absorption edge which resulted in the reduction of band gap from 3.23 to 3.21 eV. These physicochemical properties of TiO2 NPs were correlated with photocatalytic degradation of phenol. About 92% of phenol degradation was observed for surfactant assisted TiO2 NPs (SA-TiO2). Salicylic acid and caffeine were also degraded using SA-TiO2 NPs.


2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Shengtao Hei ◽  
Yan Jin ◽  
Fumin Zhang

Porousγ-Fe2O3nanoparticles were prepared via a solid-state conversion process of a mesoporous iron(III) carboxylate crystal, MIL-100(Fe). First, the MIL-100(Fe) crystal that served as the template of the metal oxide was synthesized by a low-temperature (<100°C) synthesis route. Subsequently, the porousγ-Fe2O3nanoparticles were fabricated by facile thermolysis of the MIL-100(Fe) powders via a two-step calcination treatment. The obtainedγ-Fe2O3was characterized by X-ray diffraction (XRD), N2adsorption, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM) techniques, and then used as an adsorbent for heavy metal ions removal in water treatment. This study illustrates that the metal-organic frameworks may be suitable precursors for the fabrication of metal oxides nanomaterials with large specific surface area, and the prepared porousγ-Fe2O3exhibits a superior adsorption performance for As(V) and As(III) ions removal in water treatment.


2018 ◽  
Vol 14 (3) ◽  
pp. 209-215 ◽  
Author(s):  
Wenjie Zhang ◽  
Yuxuan Liu ◽  
Hongliang Xin

Background: The potential of applying TiO2-based materials has been ascertained in both wastewater and polluted air. Boron is proven to be an effective dopant to promote the activity of TiO2 in our previous work. The density of hollow material is little larger than water so that the hollow photocatalyst can suspend in wastewater under stirring or aeration. Methods: The graphical spheres were prepared from glucose using hydrothermal method. The hollow spherical x%B-TiO2 was synthesized through a sol-gel route, using tetrabutyl titanate and tributyl borate in the precursor. The materials were characterized by X-ray diffraction, scanning electron microscope, infrared spectrum, X-ray photoelectron spectroscopy, and N2 adsorption-desorption techniques. Photocatalytic degradation of RBR X-3B dye was studied to show the activity of the x%B-TiO2 materials. Results: Anatase TiO2 phase forms in all the x%B-TiO2 samples despite the difference in boron content. An absolute Ti4+ oxidation state exists in the x%B-TiO2, which is hardly affected by the doped boron. XPS analysis proves the formation of B-Ti-O structure in anatase TiO2 lattice. BET surface area increases with rising boron doping content in the hollow spherical x%B-TiO2 samples. Photocatalytic activity of TiO2 is enhanced after doping boron. The photocatalytic efficiency on RBR X- 3B degradation reaches the maximum value when n(B)/n(Ti) is 8%. After five photocatalytic cycles, decoloration efficiency on 8%B-TiO2 is as much as 80% of the initial value. Conclusion: A continuous expansion of TiO2 crystal happens with increasing boron content. The Ti4+ oxidation state of titanium in the hollow spherical material is not changed after doping boron. BET surface area of the hollow spherical x%B-TiO2 increases with rising boron doping content. The hollow spherical 8%B-TiO2 has satisfactory performs for recycling and lifetime.


2020 ◽  
Vol 13 (1) ◽  
pp. 1933-1944 ◽  
Author(s):  
Olga E. Shapovalova ◽  
Andrey S. Drozdov ◽  
Ekaterina A. Bryushkova ◽  
Maxim I. Morozov ◽  
Vladimir V. Vinogradov

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Hua Chen ◽  
Jianhua Wang ◽  
Huajun Wang ◽  
Fei Yang ◽  
Jia-nan Zhou ◽  
...  

TiO2/stellerite composite photocatalysts were prepared by dispersing TiO2 onto the surface of HCl, NaOH, or NaCl treated stellerite using a sol-gel method. The materials were characterized by scanning electron microscopy (SEM), energy dispersive X-ray (EDX), Fourier transform infrared spectroscopy (FT-IR), BET surface area analysis, and X-ray diffraction (XRD). HCl and NaCl modification result in the promotion of the pore formation at the stellerite surfaces and induced the microscopic changes, while the surface morphology and structure of the stellerite were almost ruined by NaOH modification. Supported TiO2 calcinated at 200°C presented anatase structure. The photocatalytic degradation activities of TiO2 loaded HCl and NaCl modified stellerite were better than that of natural stellerite, accompanied with increasing specific surface area. On the contrary, NaOH modification induced the loss of photocatalytic ability of composite due to the generation of silicates.


Author(s):  
Tarek A. Gad Allah ◽  
Shigeru Kato ◽  
Shigeo Satokawa ◽  
Toshinori Kojima

Magnetic titanium dioxide particles were prepared by depositing different amounts of TiO2 on magnetite powder using a sol-gel process. Adsorptivity of TiO2/Fe3O4 particles was increased by carbon coating which was carried out by mixing the particles with poly (vinyl alcohol) as a source of carbon. The carbon coating and calcination of particles were carried out simultaneously by heating the mixture at different temperatures. X-ray diffraction, energy dispersion fluorescence x-ray spectrometry, carbon-nitrogen analyzer and surface area analysis were used for the characterization of the prepared samples. The phase transition temperature of TiO2 from anatase to rutile was found to decrease by decreasing titanium tetraisopropoxide to magnetite (TTIP:Fe3O4) ratio while BET surface area increased by increasing this ratio. Carbon content had a significant effect on the formed phases and surface areas of the samples. The photocatalytic efficiencies of the prepared samples were investigated against degradation of methyl orange. The effect of TTIP:Fe3O4 ratio and carbon content on the degradation rate were studied. Methyl orange degradation rate increased with the increase in TTIP:Fe3O4 ratio but decreased by increasing carbon content.


Processes ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 1238
Author(s):  
Garven M. Huntley ◽  
Rudy L. Luck ◽  
Michael E. Mullins ◽  
Nick K. Newberry

Four naturally occurring zeolites were examined to verify their assignments as chabazites AZLB-Ca and AZLB-Na (Bowie, Arizona) and clinoptilolites NM-Ca (Winston, New Mexico) and NV-Na (Ash Meadows, Nevada). Based on powder X-ray diffraction, NM-Ca was discovered to be mostly quartz with some clinoptilolite residues. Treatment with concentrated HCl (12.1 M) acid resulted in AZLB-Ca and AZLB-Na, the chabazite-like species, becoming amorphous, as confirmed by powder X-ray diffraction. In contrast, NM-Ca and NV-Na, which are clinoptilolite-like species, withstood boiling in concentrated HCl acid. This treatment removes calcium, magnesium, sodium, potassium, aluminum, and iron atoms or ions from the framework while leaving the silicon framework intact as confirmed via X-ray fluorescence and diffraction. SEM images on calcined and HCl treated NV-Na were obtained. BET surface area analysis confirmed an increase in surface area for the two zeolites after treatment, NM-Ca 20.0(1) to 111(4) m2/g and NV-Na 19.0(4) to 158(7) m2/g. 29Si and 27Al MAS NMR were performed on the natural and treated NV-Na zeolite, and the data for the natural NV-Na zeolite suggested a Si:Al ratio of 4.33 similar to that determined by X-Ray fluorescence of 4.55. Removal of lead ions from solution decreased from the native NM-Ca, 0.27(14), NV-Na, 1.50(17) meq/g compared to the modified zeolites, 30 min HCl treated NM-Ca 0.06(9) and NV-Na, 0.41(23) meq/g, and also decreased upon K+ ion pretreatment in the HCl modified zeolites.


2021 ◽  
pp. 125408
Author(s):  
Yanchen Zhu ◽  
Xin Wang ◽  
Zilong Li ◽  
Yunxiang Fan ◽  
Xujing Zhang ◽  
...  

Nanomaterials ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1068
Author(s):  
Xinyue Zhang ◽  
Yani Guo ◽  
Wenjun Li ◽  
Jinyuan Zhang ◽  
Hailiang Wu ◽  
...  

The treatment of wastewater containing heavy metals and the utilization of wool waste are very important for the sustainable development of textile mills. In this study, the wool keratin modified magnetite (Fe3O4) powders were fabricated by using wool waste via a co-precipitation technique for removal of Cu2+ ions from aqueous solutions. The morphology, chemical compositions, crystal structure, microstructure, magnetism properties, organic content, and specific surface area of as-fabricated powders were systematically characterized by various techniques including field emission scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), vibrating sample magnetometer (VSM), thermogravimetric (TG) analysis, and Brunauer–Emmett–Teller (BET) surface area analyzer. The effects of experimental parameters such as the volume of wool keratin hydrolysate, the dosage of powder, the initial Cu2+ ion concentration, and the pH value of solution on the adsorption capacity of Cu2+ ions by the powders were examined. The experimental results indicated that the Cu2+ ion adsorption performance of the wool keratin modified Fe3O4 powders exhibited much better than that of the chitosan modified ones with a maximum Cu2+ adsorption capacity of 27.4 mg/g under favorable conditions (0.05 g powders; 50 mL of 40 mg/L CuSO4; pH 5; temperature 293 K). The high adsorption capacity towards Cu2+ ions on the wool keratin modified Fe3O4 powders was primarily because of the strong surface complexation of –COOH and –NH2 functional groups of wool keratins with Cu2+ ions. The Cu2+ ion adsorption process on the wool keratin modified Fe3O4 powders followed the Temkin adsorption isotherm model and the intraparticle diffusion and pseudo-second-order adsorption kinetic models. After Cu2+ ion removal, the wool keratin modified Fe3O4 powders were easily separated using a magnet from aqueous solution and efficiently regenerated using 0.5 M ethylene diamine tetraacetic acid (EDTA)-H2SO4 eluting. The wool keratin modified Fe3O4 powders possessed good regenerative performance after five cycles. This study provided a feasible way to utilize waste wool textiles for preparing magnetic biomass-based adsorbents for the removal of heavy metal ions from aqueous solutions.


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