Hydrochloric Acid Modification and Lead Removal Studies on Naturally Occurring Zeolites from Nevada, New Mexico, and Arizona.

Four naturally occurring zeolites AZLB-Ca and AZLB-Na (Bowie, Arizona), NM-Ca (Winston, New Mexico), and NV-Na (Ash Meadows, Nevada) were studied to evaluate structural modifications after treatment with HCl acid. AZLB-Ca and AZLB-Na are chabazite-like species and become amorphous when boiled in concentrated HCl acid 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.

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Hydrochloric Acid Modification and Lead Removal Studies on Naturally Occurring Zeolites from Nevada, New Mexico, and Arizona

Processes ◽

10.3390/pr9071238 ◽

2021 ◽

Vol 9 (7) ◽

pp. 1238

Author(s):

Garven M. Huntley ◽

Rudy L. Luck ◽

Michael E. Mullins ◽

Nick K. Newberry

Keyword(s):

New Mexico ◽

Surface Area ◽

Bet Surface Area ◽

Lead Removal ◽

X Ray Diffraction ◽

Sem Images ◽

X Ray ◽

Naturally Occurring ◽

27Al Mas Nmr ◽

Modified Zeolites

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.

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Adsorptive Removal of Methylene Blue and Crystal Violet onto Micro-Mesoporous Zr3O/Activated Carbon Composite: A Joint Experimental and Statistical Modeling Considerations

Journal of Chemistry ◽

10.1155/2018/6982014 ◽

2018 ◽

Vol 2018 ◽

pp. 1-14 ◽

Cited By ~ 8

Author(s):

H. Ait Ahsaine ◽

Z. Anfar ◽

M. Zbair ◽

M. Ezahri ◽

N. El Alem

Keyword(s):

Methylene Blue ◽

Activated Carbon ◽

Surface Area ◽

Crystal Violet ◽

Zirconium Oxide ◽

Carbon Composite ◽

Bet Surface Area ◽

Sem Images ◽

X Ray ◽

Pseudo Second Order

Zirconium oxide/activated carbon (Zr3O/AC) composite was synthesized to remove methylene blue (MB) and crystal violet (CV) from the aqueous medium. The Zr3O/AC sample was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analyses (EDS), Raman spectroscopy (RS), BET surface area, and Fourier transform infrared spectroscopy (FTIR). XRD profiles confirmed the successful synthesis of the zirconium oxide/activated carbon composite. SEM images showed multideveloped walls with irregular particle size with channel arrays. The nitrogen physisorption combines I and IV types with a calculated BET surface area of 1095 m2/g. Raman spectrum illustrated a disorder of both crystalline structure and the graphitic structure. The adsorption was better fitted to the pseudo-second-order (PSO) kinetic model. Langmuir model fitted better the experimental results of MB adsorption, whereas the CV was better consistent with the Freundlich model. The obtained results suggested that the MB and CV adsorption might be influenced by the mass transfer that involves multiple diffusion steps. The maximum adsorption capacities are 208.33 and 204.12 mg/g for MB and CV, respectively. The MB and CV removal mechanisms were proposed, and statistical optimization was performed using central composite design combined with the response surface methodology.

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Physicochemical Properties of Oxalic Acid-Modified Chitosan/Neem Leave Composites from Pessu River Crab Shell

International Journal of Chemical Reactor Engineering ◽

10.1515/ijcre-2018-0274 ◽

2019 ◽

Vol 17 (9) ◽

Author(s):

Oluwadayo Francis Asokogene ◽

Muhammad Abbas Ahmad Zaini ◽

Misau Muhammad Idris ◽

Surajudeen Abdulsalam ◽

Aliyu El-Nafaty Usman

Keyword(s):

Methylene Blue ◽

Oxalic Acid ◽

Surface Area ◽

Dye Adsorption ◽

Textural Properties ◽

Bet Surface Area ◽

Blue Dye ◽

Crab Shell ◽

Sem Images ◽

X Ray

Abstract This study was aimed to evaluate the characteristics of chitosan from Pessu river crab shell and its derivatives as prospective adsorbent. The synthesized chitosan (CH) was modified with 10 % (w/v) oxalic acid (CHOx), while the composites (CHOx-ANL1, CHOx-ANL2 and CHOx-ANL3) were designated according to the amount of activated neem leave (ANL). The materials were characterized by Fourier transform infrared (FTIR), energy-dispersive X-ray (EDAX), X-ray diffraction (XRD), scanning electron microscope (SEM), Brunauer-Emmett-Teller (BET), thermal gravimetric (TGA) and methylene blue dye adsorption. The FTIR spectra of chitosan samples show the characteristics of primary and secondary amine/amide groups. The SEM images exhibit a tight, porous and fractured surface, which is covered with activated neem leave for the composites. The BET surface area of chitosan materials is in the increasing order of, CH < CHOx-ANL1 < CHOx-ANL2 < CHOx < CHOx-ANL3. CHOx-ANL3 displays a higher surface area of 389 m2/g, and 70.9 % mesoporosity. Despite its lower surface area of 258 m2/g (65.4 % mesoporosity), CHOx-ANL1 exhibits a greater methylene blue adsorption of 90.8 mg/g at dye concentration of 300 mg/L. The possible removal mechanisms include ionic interaction between dye molecules and functional groups, and surface adsorption due to the textural properties of chitosan samples. Chitosan from Pessu river crab shell and its derivatives are promising adsorbent candidate for dyes and heavy metals removal from water.

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Magnetically Recyclable Wool Keratin Modified Magnetite Powders for Efficient Removal of Cu2+ Ions from Aqueous Solutions

Nanomaterials ◽

10.3390/nano11051068 ◽

2021 ◽

Vol 11 (5) ◽

pp. 1068

Author(s):

Xinyue Zhang ◽

Yani Guo ◽

Wenjun Li ◽

Jinyuan Zhang ◽

Hailiang Wu ◽

...

Keyword(s):

Electron Microscopy ◽

Aqueous Solutions ◽

Adsorption Capacity ◽

Surface Area ◽

Ion Concentration ◽

Bet Surface Area ◽

Chemical Compositions ◽

Ion Adsorption ◽

X Ray ◽

Wool Keratin

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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Synthesis and Characterization of Hematite Nanoparticles as Active Photocatalyst for Water Splitting Application

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.594-595.73 ◽

2013 ◽

Vol 594-595 ◽

pp. 73-77 ◽

Cited By ~ 1

Author(s):

Sze Mei Chin ◽

Suriati Sufian ◽

Jeefferie Abd Razak

Keyword(s):

Surface Area ◽

Water Splitting ◽

Combustion Method ◽

Hydrogen Gas ◽

Bet Surface Area ◽

Synthesis And Characterization ◽

Hematite Nanoparticles ◽

X Ray ◽

Bet Specific Surface Area

This paper highlights on the hydrogen production through photocatalytic activity by using hematite nanoparticles synthesized from self-combustion method based on different stirring period. The morphologies and microstructures of the nanostructures were determined using Field-Emission Scanning Electron Microscope (FESEM), X-Ray Diffractometer (XRD) and Particle Size Analyser (PSA). Besides that, surface area analyser was used to determine the BET surface area of the hematite samples. The hematite nanocatalyst as-synthesized are proven to be rhombohedral crystalline hematite (α-Fe2O3) with particle diameters ranging from 60-140 nm. The BET specific surface area of hematite samples increased from 5.437 to 7.6425 m2/g with increasing stirring period from 1 to 4 weeks. This caused the amount of hydrogen gas produced from photocatalytic water splitting to increase as well.

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Synthesis and Characterization of Co-Mo/γ-Alumina Catalyst from local Kaolin clay for Hydrodesulfurization of Iraqi Naphtha

Journal of Petroleum Research and Studies ◽

10.52716/jprs.v11i1.431 ◽

2021 ◽

Vol 11 (1) ◽

pp. 84-106

Author(s):

Nada Sadoon Ahmed zeki ◽

Sattar Jalil Hussein ◽

Khalifa K. Aoyed ◽

Saad Kareem Ibrahim ◽

Ibtissam K. Mehawee

Keyword(s):

Surface Area ◽

Sulfur Removal ◽

Sulfuric Acid Concentration ◽

Bet Surface Area ◽

X Ray Diffraction ◽

X Ray ◽

Mo Catalyst ◽

Pressure Time ◽

Al2o3 Catalyst

This work deals with the hydrodesulfurization of three types of naphtha feedstocks; mixednaphtha (WN), heavy naphtha (HN) & light naphtha (LN) with a sulfur content of 1642.1,1334.9 & 709 ppm respectively, obtained from Missan refinery using prepared Co-Mo/γ-Al2O3catalyst. The Iraqi white kaolin was used as a starting material for the preparation of γ-Al2O3support, transferring kaolin to meta-kaolin was studied through calcination at differenttemperatures and durations, kaolin structure was investigated using X-Ray diffractiontechniques.High purity 94.83%. Crystalline γ-Al2O3 with a surface area of 129.91 m2/gm, pore volume0.9002 cm3/g was synthesized by extraction of Iraqi kaolin with H2SO4 at different acid to clayweight ratios, acid concentrations & leaching time. Ethanol was used as precipitating agent; theresultant gel was dried and calcined at 70OC, 10 hrs & 900 OC, 2 hrs respectively.The effects of different parameters on the average crystallinity and extraction % ofsynthesized γ-Al2O3 were studied like; acid: clay ratio, sulfuric acid concentration, leachingtime, leaching temperature & kaolin conversion to metakaolin. Characterization of prepared γ-Al2O3 & Co-Mo catalyst were achieved by X-ray diffraction, FTIR-spectra, texture properties& BET surface area, BJH N2 adsorption porosity, AFM, SEM, crush strength & XRF tests. Co-Mo/ γ-Al2O3 catalyst with final loading 5.702 wt% and 21.45 wt% of Co and Mo oxidesrespectively was prepared by impregnation methods.The activity of prepared Co-Mo/γ-Al2O3 catalyst after moulding to be tested forhydrodesulfurization (HDS) of naphtha feedstock W.N, H.N & L.N was performed using apilot hydrotreating unit at petroleum research & development centre, at different operatingconditions. Effects of temperature, LHSV, pressure, time & pore size distribution were studied,the best percentage of sulfur removal is increased with decreasing LHSV to 2 hr-1 as a generaltrend to be 89.71, 99.72, 99.20 % at 310oC for the whole naphtha, heavy naphtha and lightnaphtha feedstocks respectively, at 34 bar pressure and 200/200 cm3/cm3 H2/HC ratio.

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Olive Leaves as Biotemplates for Enhanced Solar-Light Harvesting by a Titania-Based Solid

Nanomaterials ◽

10.3390/nano10061057 ◽

2020 ◽

Vol 10 (6) ◽

pp. 1057

Author(s):

Jesús Hidalgo-Carrillo ◽

Juan Martín-Gómez ◽

M. Carmen Herrera-Beurnio ◽

Rafael C. Estévez ◽

Francisco J. Urbano ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Electron Paramagnetic Resonance Spectroscopy ◽

Average Particle Size ◽

Solar Irradiation ◽

Bet Surface Area ◽

Resonance Spectroscopy ◽

Average Particle ◽

Olive Leaves ◽

Sem Images ◽

X Ray

Olive leaves (by-product from olive oil production in olive mills) were used as biotemplates to synthesize a titania-based artificial olive leaf (AOL). Scanning electron microscopy (SEM) images of AOL showed the successful replication of trichomes and internal structure channels present in olive leaves. The BET surface area of AOL was 52 m2·g−1. X-ray diffraction (XRD) and Raman spectra revealed that the resulting solid was in the predominantly-anatase crystalline form (7.5 nm average particle size). Moreover, the synthesis led to a red-shift in light absorption as compared to reference anatase (gap energies of 2.98 and 3.2 eV, respectively). The presence of surface defects (as evidenced by X-ray photoelectron spectroscopy, XPS, and electron paramagnetic resonance spectroscopy, EPR) and doping elements (e.g., 1% nitrogen, observed by elemental analysis and XPS) could account for that. AOL was preliminarily tested as a catalyst for hydrogen production through glycerol photoreforming and exhibited an activity 64% higher than reference material Evonik P25 under solar irradiation and 144% greater under ultraviolet radiation (UV).

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

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.257.187 ◽

2016 ◽

Vol 257 ◽

pp. 187-192 ◽

Cited By ~ 2

Author(s):

Mohamed Ali Ghanem ◽

Nezar H. Khdary ◽

Abdullah M. Almayouf ◽

Mabrook A. Salah

Keyword(s):

Metal Ions ◽

Surface Area ◽

Self Assembly ◽

Sol Gel ◽

Bet Surface Area ◽

Ionic Exchange ◽

Characteristic Structure ◽

X Ray ◽

Heavy Metal Ions Removal ◽

Metal Ions Removal

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.

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The Photocatalytic and Antibacterial Performance of Nitrogen-Doped TiO2: Surface-Structure Dependence and Silver-Deposition Effect

Nanomaterials ◽

10.3390/nano10112261 ◽

2020 ◽

Vol 10 (11) ◽

pp. 2261 ◽

Cited By ~ 2

Author(s):

Abdul Wafi ◽

Erzsébet Szabó-Bárdos ◽

Ottó Horváth ◽

Mihály Pósfai ◽

Éva Makó ◽

...

Keyword(s):

Electron Microscopy ◽

Visible Light ◽

Surface Area ◽

Photocatalytic Performance ◽

Visible Region ◽

Bet Surface Area ◽

Doped Tio2 ◽

X Ray ◽

Nitrogen Doped ◽

Visible Light Driven

Catalysts for visible-light-driven oxidative cleaning processes and antibacterial applications (also in the dark) were developed. In order to extend the photoactivity of titanium dioxide into the visible region, nitrogen-doped TiO2 catalysts with hollow and non-hollow structures were synthesized by co-precipitation (NT-A) and sol–gel (NT-U) methods, respectively. To increase their photocatalytic and antibacterial efficiencies, various amounts of silver were successfully loaded on the surfaces of these catalysts by using a facile photo-deposition technique. Their physical and chemical properties were evaluated by using scanning electron microscopy (SEM), transmission electron microscopy–energy dispersive X-ray spectroscopy (TEM–EDS), Brunauer–Emmett–Teller (BET) surface area, X-ray diffraction (XRD), and diffuse reflectance spectra (DRS). The photocatalytic performances of the synthesized catalysts were examined in coumarin and 1,4-hydroquinone solutions. The results showed that the hollow structure of NT-A played an important role in obtaining high specific surface area and appreciable photoactivity. In addition, Ag-loading on the surface of non-hollow structured NT-U could double the photocatalytic performance with an optimum Ag concentration of 10−6 mol g−1, while a slight but monotonous decrease was caused in this respect for the hollow surface of NTA upon increasing Ag concentration. Comparing the catalysts with different structures regarding the photocatalytic performance, silverized non-hollow NT-U proved competitive with the hollow NT-A catalyst without Ag-loading for efficient visible-light-driven photocatalytic oxidative degradations. The former one, due to the silver nanoparticles on the catalyst surface, displayed an appreciable antibacterial activity, which was comparable to that of a reference material practically applied for disinfection in polymer coatings.

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Green synthesis of TiO2 nanoparticles from Syzygium cumini extract for photo-catalytic removal of lead (Pb) in explosive industrial wastewater

Green Processing and Synthesis ◽

10.1515/gps-2020-0018 ◽

2020 ◽

Vol 9 (1) ◽

pp. 171-181 ◽

Cited By ~ 6

Author(s):

Naresh Kumar Sethy ◽

Zeenat Arif ◽

Pradeep Kumar Mishra ◽

Pradeep Kumar

Keyword(s):

Electron Microscopy ◽

High Resolution ◽

Green Synthesis ◽

Industrial Wastewater ◽

Anatase Phase ◽

Bet Surface Area ◽

Lead Removal ◽

Syzygium Cumini ◽

X Ray ◽

Catalytic Removal

AbstractGreen synthesis is a simple, non-toxic, economical and eco-friendly approach for the synthesis of nanoparticles. In the present work, nanoparticles of titanium dioxide (TiO2 NPs) were synthesized using an aqueous solution of Syzygium cumini leaf extract as a capping agent. These green synthesized TiO2 NPs were further evaluated for photo catalytic removal of lead from industrial wastewater. Obtained nanoparticles were characterized using: high-resolution scanning electron microscopy (HRSEM), high-resolution transmission electron microscopy (HRTEM), X-ray energy dispersive spectroscopy (EDS), Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), dynamic light scattering (DLS) and Brunauer-Emmett-Teller (BET). Obtained results revealed that synthesized TiO2 NPs possess spherical morphology with anatase phase with a large BET surface area of 105 m2/g. Photo catalytic studies of TiO2 NPs for lead removal from explosive wastewater were performed in a self-designed reactor. Inductive coupled plasma spectroscopy (ICP) was used to determine the lead concentration. Obtained results witnessed 75.5% removal in chemical oxygen demand (COD) and 82.53% removal in lead (Pb2+). This application of green TiO2 NPs is being explored for the first time.

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