Co Precipitation
Mostrando 1-12 de 262 artigos, teses e dissertações.
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1. Influence of Refinery Asphalt Residue Addition on Flow: A Study Using Waxy Model-System
One of the main phenomena causing problems in the oil industry is the precipitation of waxes, which can crystallize and form deposits, clogging lines and reducing flows. Many studies have been conducted seeking to overcome this problem, mainly through application of chemical to increase flow. Some studies have shown that the asphaltenes present in crude oil
Journal of the Brazilian Chemical Society. Publicado em: 2023
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2. New Attempts to Synthesize Layered Double Hydroxides Intercalated with SO42-/Cs+ Using Co-Precipitation and Exchange Reactions
Layered double hydroxides (LDHs) with the compositions (Cs+/NH4+)0.111[M2+0.667Al0.333(OH)2.0 (SO4)0.222] (M2+ = Mn, Zn) and basal distance of ca. 11 Å were obtained by co-precipitating Mn/Al and Zn/Al sulfate salts with aqueous NH3, using excess of Cs2SO4. [Mn0.667Al3+0.333(OH)2]Cl0.333.nH2O and [M2+0.667Al3+0.333(OH)2](NO3)0.333.nH2O (M2+ = Mn, Zn) were a
Journal of the Brazilian Chemical Society. Publicado em: 2022
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3. EFFECT OF REACTION CONDITIONS ON PARTICLE SIZE OF ZNO NANOPARTICLES VIA CONTROLLED PRECIPITATION METHOD AND IN-VITRO ANTIBACTERIAL CAPACITY
High-yield ZnO spheroidal nanoparticles with an average diameter around 23 nm (≈ 25% frequency) and 30 nm (≈ 28% frequency) were obtained by controlled semicontinuous precipitation at low temperatures. This synthesis was obtained from hydrozincite (Zn5(CO3)2(OH)6) as primary nanoparticles. The Zn5(CO3)2(OH)6 nanoparticles were synthesized by hydrolysis o
Química Nova. Publicado em: 2022
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4. Influence of the Local Structure on the Photocatalytic Properties of Zinc Spinel Ferrite Nanoparticles
The correlation between iron distribution in octahedral or tetrahedral sites in synthetic magnetite and zinc spinel ferrites and their catalytic properties were investigated in this work. The zinc-doped nanomagnetites were prepared by co-precipitation method and annealed at 420 °C. X-ray diffraction, UV-Vis, X-ray absorption and 57Fe Mössbauer spectroscopi
Journal of the Brazilian Chemical Society. Publicado em: 2022
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5. Tuning the Photocatalytic Activity of Tin Oxide through Mechanical Surface Activation
Tin oxide (SnO2) nanoparticles were synthesized by the co-precipitation method and mechanically modified by high-energy ball milling. The experimental results demonstrate that the collision with zirconia balls produces slight changes in the crystalline, electronic, morphological, and surface properties of SnO2, which lead to an increase in the redox potentia
Journal of the Brazilian Chemical Society. Publicado em: 2022
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6. Preparation and performance of magnetic zirconium-iron oxide nanoparticles loaded on palygorskite in the adsorption of phosphate from water
Magnetic zirconium-iron oxide nanoparticles loaded on palygorskite as a low-cost adsorbent was produced by one-step co precipitation technique and its properties for phosphate adsorption were overall investigated. The Brunauer Emmett Teller (BET) specific surface area analysis, scanning electron microscopy (SEM), thermo gravimetric analysis (TGA), Fourier tr
Química Nova. Publicado em: 2022
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7. Ferrimagnetic to paramagnetic transition and dielectric relaxation in Ni1-xZnxFe2O4 ferrites
Abstract The spinel ferrite system Ni1-xZnxFe2O4 (x=0-0.7, Δx=0.1) was prepared by wet chemical co-precipitation method using sulfates of respective metal ions. The electrical resistivity and dielectric properties of the prepared samples have been studied as a function of temperature, frequency, and Zn content (x). The DC resistivity (ϱ) was measured in th
Cerâmica. Publicado em: 2021-06
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8. Synthesis, Characterization and Exchange Reactions of Layered Double Hydroxides of Copper and Aluminum, Intercalated with Sulfate
Layered double hydroxides (LDHs) of Cu:Al in the molar ratio of 2:1, intercalated with sulfate, sulfate/(Li+, Na+, K+ or NH4+), NO3- and CO32-, were synthesized by co-precipitation with increasing pH. The materials were submitted to exchange reactions using B2SO4 (B = Li+, Na+, K+, NH4+) solutions in an attempt to replace previously intercalated cations or i
J. Braz. Chem. Soc.. Publicado em: 2021-01
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9. Arsenic and Other Elements Determination in Seawater Using Coprecipitation and Standard Mode Inductively Coupled Plasma Mass Spectrometry
The present work aims the determination of As, Co, Cr, Cu, Mn and Pb in seawater samples using coprecipitation extraction procedure before standard mode inductively coupled plasma mass spectrometry (ICP-MS) (no collision/reaction cell). The coprecipitation procedure is based on the precipitation of Mg(OH)2 from the reaction of the Mg2+ ions (present into the
J. Braz. Chem. Soc.. Publicado em: 2021-01
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10. Zn2Al Layered Double Hydroxides Intercalated with Nitrate and p-Aminobenzoate as Ultraviolet Protective Agents in Low-Density Polyethylene Nanocomposites and Natural Insulating Oils
Zn2Al-Cl and Zn2Al-NO3 layered double hydroxides (LDHs) were synthesized through the fixed pH co-precipitation method and used as precursor materials for the intercalation of p-aminobenzoate through anion exchange reactions. Since chloride in Zn2Al-Cl was only partially exchanged with p-aminobenzoate, the phases Zn2Al-NO3 and Zn2Al-N -AB (nitrate exchanged w
J. Braz. Chem. Soc.. Publicado em: 2020-05
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11. Síntese e caracterização de nanopartículas de Fe3O4@SiO2
RESUMO Neste trabalho foi estudada a síntese e caracterização das nanopartículas magnéticas de magnetita (Fe3O4) através da co-precipitação e, sua posterior funcionalização pela sílica (SiO2), realizada via metodologia sol-gel. A caracterização das nanopartículas foi feita por difratometria de raios X (DRX), microscopia eletrônica de transmiss
Matéria (Rio J.). Publicado em: 25/11/2019
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12. Degradation of Acid Red 8 Dye Using Photo-Fenton Reaction Mediated by Titanium Modified Catalysts
Catalysts prepared by co-precipitation of iron and titanium were evaluated in heterogeneous photo-Fenton degradation of the azo dye Acid Red 8 under blacklight irradiation. Materials with different titanium contents (0 < Ti/Fe < 0.6) were characterized using X-ray diffractometry, scanning electron microscopy, X-ray fluorescence spectroscopy, specific surface
J. Braz. Chem. Soc.. Publicado em: 21/10/2019