Co‐Precipitation of Fe−Cu Bimetal Oxalates in an Aqueous Solution and Their Thermally Induced Decomposition

2021 ◽  
Vol 2021 (37) ◽  
pp. 3886-3895
Author(s):  
Josef Kopp ◽  
Petr Novák ◽  
Soňa Lisníková ◽  
Vlastimil Vrba ◽  
Vít Procházka
Keyword(s):  
Aqueous Solution ◽  
Thermally Induced ◽  
Induced Decomposition ◽  
Co Precipitation

scholarly journals Thermoresponsive Polymers as Macromolecular Coordination Ligands: Complexation-Dependence of Thermally Induced Aggregation in Aqueous Solution

2021 ◽  
Author(s):  
Maximilian Felix Toni Meier ◽  
Franck Thetiot ◽  
Narsimhulu Pittala ◽  
Ingo Lieberwirth ◽  
Cleiton Kunzler ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Thermoresponsive Polymers ◽  
Thermally Induced ◽  
Coordination Sites ◽  
Induced Aggregation

We have designed novel macromolecular coordination ligands (MCLs) by conjugation of thermoresponsive polymers based on poly(N-isopropylacrylamide) (M ̅_n around 3 to 25 kg∙mol-1) with 1,2,4-triazole coordination sites. These triazole units...

scholarly journals Synthesis of Nanoscale Zerovalent Iron (nZVI) Supported on Biochar for Chromium Remediation from Aqueous Solution and Soil

2019 ◽  
Vol 16 (22) ◽  
pp. 4430 ◽  
Author(s):  
Haixia Wang ◽  
Mingliang Zhang ◽  
Hongyi Li
Keyword(s):  
Aqueous Solution ◽  
Photoelectron Spectroscopy ◽  
Zero Valent Iron ◽  
Zerovalent Iron ◽  
X Ray ◽  
Nanoscale Zerovalent Iron ◽  
Before And After ◽  
Pseudo Second Order ◽  
Xrd Patterns ◽  
Co Precipitation

Maize straw biochar-supported nanoscale zero-valent iron composite (MSB-nZVI) was prepared for efficient chromium (Cr) removal through alleviating the aggregation of zero-valent iron particles. The removal mechanism of MSB-nZVI was investigated by scanning electron microscopy with energy dispersive X-ray (SEM-EDX), X-ray diffractometry (XRD), and X-ray photoelectron spectroscopy (XPS). Cr(VI) removal from aqueous solution by MSB-nZVI was greatly affected by pH and initial concentration. The removal efficiency of Cr(VI) decreased with increasing pH, and the removal kinetics followed the pseudo-second-order model. XRD patterns of MSB-nZVI before and after reaction showed that reduction and precipitation/co-precipitation (FeCr2O4, Fe3O4, Fe2O3) occurred with the conversion of Cr(VI) to Cr(III) and Fe(0) to Fe(II)/Fe(III). The produced precipitation/co-precipitation could be deposited on the MSB surface rather than being only coated on the surface of nZVI particles, which can alleviate passivation of nZVI. For remediation of Cr(VI)-contaminated saline–alkali soil (pH 8.6–9.0, Cr 341 mg/kg), the released amount of Cr(VI) was 70.7 mg/kg, while it sharply decreased to 0.6–1.7 mg/kg at pH 4.0–8.0, indicating that the saline–alkali environment inhibited the remediation efficiency. These results show that MSB-nZVI can be used as an effective material for Cr(VI) removal from aqueous solution and contaminated soil.

scholarly journals Photo-Induced Decomposition of 2-Chloroaniline in Aqueous Solution

2002 ◽  
Vol 57 (5-6) ◽  
pp. 512-515 ◽  
Author(s):  
Ermin Katrin Winarno ◽  
Nikola Getoff
Keyword(s):  
Aqueous Solution ◽  
Degradation Products ◽  
Chloride Ions ◽  
Pure Oxygen ◽  
Ammonium Ions ◽  
Probable Reaction Mechanism ◽  
Specific Analysis ◽  
Probable Reaction ◽  
Uv Dose ◽  
Induced Decomposition

A study was performed on the oxidizing degradation of 2-chloroaniline (used as a model pollutant in water) by photolysis (λ = 254 nm). The change of spectrum and substrate concentration of treated solutions was measured spectrophotometrically as well as by HPLC. The yields of the degradation products (chloride ions, ammonium ions, formaldehyde, etc.) were studied as a function of UV-dose. Their initial quantumyields (Qi) were determined by specific analysis. It was shown that the substrate photolysis in the presence of N2O is most efficient, followed by degradation in media saturated with pure oxygen and air. A probable reaction mechanism for the photo-induced degradation of 2-ClA is presented.

scholarly journals High Encapsulation Efficiency of Magnetite Nanoparticles in Hydrophobic Polymer Microcapsules using Microsuspension Conventional Radical Polymerization

2019 ◽  
Vol 35 (2) ◽  
pp. 516-522 ◽  
Author(s):  
Jittaya Sadchaiyaphum ◽  
Pongsathon Phapugrangkul ◽  
Preeyporn Chaiyasat ◽  
Amorn Chaiyasat
Keyword(s):  
Aqueous Solution ◽  
Oleic Acid ◽  
Radical Polymerization ◽  
Magnetite Nanoparticles ◽  
Driving Force ◽  
Encapsulation Efficiency ◽  
Polymer Particle ◽  
Polymer Shell ◽  
Hydrophobic Polymer ◽  
Co Precipitation

High encapsulation efficiency of magnetite nanoparticles (MNPs; Fe3O4) in microcapsules using PDVB as a hydrophobic polymer shell was successfully achieved by microsuspension conventional radical polymerization (ms CRP). MNPs were initially synthesized by co-precipitation of Fe2+/Fe3+ in a binary phase. During the nucleation of MNPs in alkaline aqueous solution existing oleic acid (OA), MNPs were coated with OA (MNPs-OA) before moving to the toluene phase with the addition of salt. At OA concentration of 0.3 wt%, most of the nucleated MNPs were hydrophobic and well dispersed in the toluene phase. Using DVB as a monomer for ms CRP, high encapsulation efficiency (92 %EE) of MNPs-OA was obtained, with low free polymer particle formation. By contrast, large amounts of free polymer particles were observed at low %EE (32%) of MNPs. The main driving force for high %EE was obtained by coating the surface of the MNPs by OA which increased hydrophobicity.

Thermally induced transformations of Fe oxide-stabilized residues from waste incineration

2001 ◽  
Vol 65 (5) ◽  
pp. 635-643 ◽  
Author(s):  
M. A. Sørensen ◽  
C. Bender Koch
Keyword(s):  
Heavy Metals ◽  
Room Temperature ◽  
Waste Incineration ◽  
Oxide Phase ◽  
Waste Incinerator ◽  
Air Pollution Control ◽  
Fe Oxide ◽  
Thermally Induced ◽  
Co Precipitation ◽  
Reducing Gases

AbstractAir pollution control (APC) facilities at waste incinerator plants produce large quantities of solid residues rich in salts and heavy metals. Heavy metals are readily released to water from the residues and it has, therefore, been found suitable to apply a rapid co-precipitation/adsorption process as a means to immobilize the toxic elements. In the ‘Ferrox process’, this immobilization is based on co-precipitation with an Fe(III) oxide formed by oxidation of Fe(II) by air in an aqueous slurry with the APC residue at alkaline pH. In this work we have undertaken a Mössbauer spectroscopy study of the Fe oxide phase formed by precipitation at room temperature and of the oxides present after heating to 600 and 900°C. The only Fe oxide observed in the Ferrox product at room temperature is a very poorly crystalline ferrihydrite. Analytical transmission electron microscopy showed that the main elements associated with the ferrihydrite are Si and Ca. Following heating to 600°C the oxide is still characterized as an amorphous Fe oxide, and it is probable that Si associated with the ferrihydrite is decisive in preventing crystallization. After the 900°C treatment a transformation into defect maghemite is observed. Reducing gases produced from carbon in the samples probably induces this transformation. It eases, thus, the reduction of Fe(III) and the consequent formation of magnetite that eventually oxidizes to maghemite during cooling in air.

scholarly journals Thermally induced conformational changes and protein–protein interactions of bovine serum albumin in aqueous solution under different pH and ionic strengths as revealed by SAXS measurements

2017 ◽  
Vol 19 (26) ◽  
pp. 17143-17155 ◽  
Author(s):  
Dmitry Molodenskiy ◽  
Evgeny Shirshin ◽  
Tatiana Tikhonova ◽  
Andrey Gruzinov ◽  
Georgy Peters ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Bovine Serum Albumin ◽  
Serum Albumin ◽  
Conformational Changes ◽  
Interaction Potential ◽  
Protein Interactions ◽  
Bovine Serum ◽  
Protein Protein Interactions ◽  
Thermally Induced ◽  
Before And After

Temperature-induced oligomerization of albumin before and after protein melting was studied using SAXS and interpreted in terms of interaction potential.

Decomposition of Ethoxyethynyl(trimethyl)tin - Studied by 119Sn and 13C NMR Spectroscopy

1999 ◽  
Vol 54 (6) ◽  
pp. 705-708 ◽  
Author(s):  
Bemd Wrackmeyer ◽  
Sergei V. Ponomarev
Keyword(s):  
Chemical Shifts ◽  
Acid Ethyl Ester ◽  
13C Nmr Spectroscopy ◽  
Major Product ◽  
Coupling Constants ◽  
Data Sets ◽  
Thermally Induced ◽  
Nmr Data ◽  
Induced Decomposition ◽  
A Minor

The thermally induced decomposition of ethoxyethynyl(trimethyl)tin (1) was studied by 119Sn NMR which revealed the formation o f bis(trimethylstannyl) ketene (2) as the major product, bis(trimethylstannyl) acetic acid ethyl ester (3) as a minor product, and a small amount o f tetramethyltin (4). Full NMR data sets, including coupling constants and isotope induced chemical shifts 1Δ12/ 13C(119Sn) are provided for 1-3 . The first example o f ultra-high resolution 119Sn NMR is shown

scholarly journals Thermally induced decomposition of single-wall carbon nanotubes adsorbed on H/Si(111)

2002 ◽  
Vol 81 (25) ◽  
pp. 4847-4849 ◽  
Author(s):  
Michael R. C. Hunt ◽  
Massimo Montalti ◽  
Yimin Chao ◽  
Satheesh Krishnamurthy ◽  
Vinod R. Dhanak ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Single Wall Carbon Nanotubes ◽  
Thermally Induced ◽  
Single Wall Carbon ◽  
Induced Decomposition

2,5-Bridged 1-Carba-arachno-pentaborane(10) Derivatives – Intermediates on the Way to Pentaalkyl-1,5-dicarba-closo-pentaboranes(5)

2015 ◽  
Vol 70 (10) ◽  
pp. 741-745 ◽  
Author(s):  
Bernd Wrackmeyer ◽  
Hans-Joerg Schanz
Keyword(s):  
Nmr Spectroscopy ◽  
Low Temperature ◽  
Thermal Degradation ◽  
Dft Calculations ◽  
Large Excess ◽  
Thermally Induced ◽  
Independent Synthesis ◽  
Induced Decomposition ◽  
C Nmr

AbstractStimulated by a report from (R. Köster, G. Benedikt, M. A. Grassberger, Liebigs Ann. Chem. 1968, 719, 187.) on a carbaborane, for which the structure of 2,3,4,5,-tetraethlyl-1-methyl-2,5-μ-(ethyl-1′,1′-diyl)-1-carba-arachno-pentaborane(10) 1 was proposed, an independent synthesis was developed. Diethyl(ethynyl)borane was generated in situ in the presence of a large excess of “Et2B–H” (hydride bath) by ethynyl/H exchange, using ethynyl(trioctyl)tin to react in a mixture with diethyl(vinyl)borane at low temperature. Hydroboration and Et2B–H-catalysed condensation afforded 1, as shown by 11B, 13C NMR spectroscopy and DFT calculations. Thermal degradation of 1 gave 2,3,4-triethyl-1,5-dimethyl-1,5-dicarba-closo-pentaborane(5), whereas the pentaethyl-1,5-dicarba-closo-pentaborane(5) resulted from thermally induced decomposition of other suitably substituted arachno carbaboranes.

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