The physico-chemical properties of 2-methoxyphenoxyacetates of Mn(II), Co(II), Ni(II) and Cu(II)

The complexes of 4-chlorophenoxyacetates of Mn(II), Co(II), Ni(II) and Cu(II) have been synthesized as polycrystalline solids, and characterized by elemental analysis, spectroscopy, magnetic studies and also by X-ray diffraction and thermogravimetric measurements. The analysed complexes have the following colours: pink for Co(II), green for Ni(II), blue for Cu(II) and a pale pink for Mn(II) compounds. The carboxylate group binds as monodentate and bidentate ligands. On heating to 1173K in air the complexes decompose in several steps. At first, they dehydrate in one step to anhydrous salts, that next decompose to the oxides of respective metals. Their magnetic moments were determined in the range of 76-303K. The results reveal them to be high-spin complexes of weak ligand fields.

Download Full-text

Complexes of light lanthanides with 2,4-dimethoxybenzoic acid

Journal of the Serbian Chemical Society ◽

10.2298/jsc0001027f ◽

2000 ◽

Vol 65 (1) ◽

pp. 27-35 ◽

Cited By ~ 4

Author(s):

Wieslawa Ferenc ◽

Agnieszka Walków-Dziewulska

Keyword(s):

Ir Spectroscopy ◽

Intermediate Formation ◽

Carboxylate Group ◽

X Ray Diffraction ◽

X Ray ◽

One Step ◽

Light Lanthanides ◽

Thermogravimetric Studies ◽

Hydrated Complexes ◽

Two Stages

The complexes of light lanthanides with 2,4-dimethoxybenzoic acid of the formula: Ln(C9H9O4)3.nH2O where Ln = La(III), Ce(III), Pr(III), Nd(III), Sm(III), Eu(III), Gd(IIII), and n = 3 for La(III), Gd(III), n = 2 for Sm(III), Eu(III), and n = 0 for Ce(III), Pr(III), Nd(III) have been synthesized and characterized by elemental analysis, IR spectroscopy, thermogravimetric studies and X-ray diffraction measurements. The complexes have colours typical for Ln 3+ ions (La, Ce, Eu, Gd-white, Sm-cream, Pr-green, Nd-violet). The carboxylate group in these complexes is a symmetrical, bidentate, chelating ligand. They are crystalline compounds characterized by various symmetry. On heating in air to 1273 K the 2,4-dimethoxybenzoates of the light lanthanides decompose in various ways. The hydrated complexes decompose in two or three steps while those of anhydrous ones only in one or two. The trihydrate of lanthanum 2,4-dimethoxybenzoate first dehydrates to form the anhydrous salt, which then decomposes to La2O3 via the intermediate formation of La2O2CO3. The hydrates of Sm(III), Eu(III), Gd(III) decompose in two stages. First, they dehydrate forming the anhydrous salts, which then decompose directly to the oxides of the respective metals. The anhydrous complexes of Ce(III), Pr(III) decompose in one step, while that of Nd(III) in two. The solubilities of the 2,4-dimethoxybenzoates of the light lanthanides in water and ethanol at 293 K are in the order of: 10 -3 mol dm -3 and 10 -4.10 -3 mol dm-3, respectively.

Download Full-text

Complexes of 4-chlorophenoxyacetates of Nd(III), Gd(III) and Ho(III)

Eclética Química Journal ◽

10.26850/1678-4618eqj.v35.1.2010.p67-75 ◽

2018 ◽

Vol 35 (1) ◽

pp. 67

Author(s):

W. Ferenc ◽

M. Bernat ◽

J. Sarzyński ◽

H. Głuchowska

Keyword(s):

Thermal Decomposition ◽

Magnetic Moments ◽

X Ray Diffraction ◽

Magnetic Studies ◽

Bridging Ligands ◽

X Ray ◽

Gaseous Products ◽

Carboxylate Groups ◽

One Step ◽

Ligand Fields

The complexes of 4-chlorophenoxyacetates of Nd(III), Gd(III) and Ho(III) have been synthesized as polycrystalline hydrated solids, and characterized by elemental analysis, spectroscopy, magnetic studies and also by X-ray diffraction and thermogravimetric measurements. The analysed complexes have the following colours: violet for Nd(III), white for Gd(III) and cream for Ho(III) compounds. The carboxylate groups bind as bidentate chelating (Ho) or bridging ligands (Nd, Gd). On heating to 1173K in air the complexes decompose in several steps. At first, they dehydrate in one step to form anhydrous salts, that next decompose to the oxides of respective metals. The gaseous products of their thermal decomposition in nitrogen were also determined and the magnetic susceptibilites were measured over the temperature range of 76-303K and the magnetic moments were calculated. The results show that 4-chlorophenoxyacetates of Nd(III), Gd(III) and Ho(III) are high-spin complexes with weak ligand fields. The solubility value in water at 293K for analysed 4-chlorophenoxyacetates is in the order of 10-4mol/dm3.

Download Full-text

Magnetic, thermal and spectroscopic properties of lanthanide(III) 2-(4-chlorophenoxy) acetates, Ln(C8H6ClO3)3•nH2O

Journal of the Serbian Chemical Society ◽

10.2298/jsc121203043f ◽

2013 ◽

Vol 78 (9) ◽

pp. 1335-1349 ◽

Cited By ~ 3

Author(s):

Wiesława Ferenc ◽

Beata Cristóvão ◽

Jan Sarzyński

Keyword(s):

Magnetic Moments ◽

Intermediate Formation ◽

Spectroscopic Properties ◽

Ligand Field ◽

X Ray Diffraction ◽

Magnetic Susceptibilities ◽

X Ray ◽

Gaseous Products ◽

Carboxylate Groups ◽

Thermogravimetric Studies

4-Chlorophenoxyacetates of lanthanides(III) were synthesized as polycrystalline hydrated solids with the general formulae: Ln(C8H6ClO3)3?2H2O (Ln = La(III), Pr(III), Sm(III), Eu(III) and Tb(III)), Ln(C8H6ClO3)3?H2O (Ln = Dy(III)) and Ln(C8H6ClO3)3?3H2O (Ln = Er(III), Tm(III), Yb(III) and Lu(III) and characterized by elemental analysis, FTIR spectroscopy, magnetic and thermogravimetric studies and also by X-ray diffraction (XRD) measurements. The complexes have colours typical for lanthanide(III) ions. The carboxylate groups bind as bidentate chelating. On heating to 1273 K in air the complexes decompose in three steps. At first they dehydrate in one stage to form anhydrous salts that next decompose to the oxides of respective metals with the intermediate formation of their oxychlorides. The gaseous products of compound thermal decomposition in nitrogen were also determined and the magnetic susceptibilities were measured over the ranges 76-303K and 1.8-303K, and their magnetic moments were calculated. The results show that 4-chlorophenoxyacetates of lanthanides(III) are high-spin complexes with weak ligand field.

Download Full-text

Theoretical Exploration of 2,2’-Bipyridines as Electro-Active Compounds in Flow Batteries

10.26434/chemrxiv.7995935.v2 ◽

2019 ◽

Author(s):

Mariano Sánchez-Castellanos ◽

Martha M. Flores-Leonar ◽

Zaahel Mata-Pinzón ◽

Humberto G. Laguna ◽

Karl García-Ruiz ◽

...

Keyword(s):

Redox Potential ◽

Active Material ◽

Chemical Properties ◽

Small Subset ◽

Solubility In Water ◽

Protonation Reaction ◽

Redox Active ◽

Physico Chemical ◽

Pka Value ◽

Flow Batteries

Compounds from the 2,2’-bipyridine molecular family were investigated for use as redox-active materials in organic flow batteries. For 156 2,2’-bipyridine derivatives reported in the academic literature, we calculated the redox potential, the pKa for the first protonation reaction, and the solubility in aqueous solutions. Using experimental data on a small subset of derivatives, we were able to calibrate our calculations. We find that functionalization with electron-withdrawing groups leads to an increase of the redox potential and to an increase of the molecular acidity (as expressed in a reduction of the pKa value for the first protonation step). Furthermore, calculations of solubility in water indicate that some of the studied derivatives have adequate solubility for flow battery applications. Based on an analysis of the physico-chemical properties of the 156 studied compounds, we down-select five molecules with carbonyl- and nitro-based functional groups, whose parameters are especially promising for potential application as negative redox-active material inorganic flow batteries.

Download Full-text

Theoretical Exploration of 2,2’-Bipyridines as Electro-Active Compounds in Flow Batteries

10.26434/chemrxiv.7995935 ◽

2019 ◽

Author(s):

Mariano Sánchez-Castellanos ◽

Martha M. Flores-Leonar ◽

Zaahel Mata-Pinzón ◽

Humberto G. Laguna ◽

Karl García-Ruiz ◽

...

Keyword(s):

Redox Potential ◽

Active Material ◽

Chemical Properties ◽

Small Subset ◽

Solubility In Water ◽

Protonation Reaction ◽

Redox Active ◽

Physico Chemical ◽

Pka Value ◽

Flow Batteries

Compounds from the 2,2’-bipyridine molecular family were investigated for use as redox-active materials in organic flow batteries. For 156 2,2’-bipyridine derivatives reported in the academic literature, we calculated the redox potential, the pKa for the first protonation reaction, and the solubility in aqueous solutions. Using experimental data on a small subset of derivatives, we were able to calibrate our calculations. We find that functionalization with electron-withdrawing groups leads to an increase of the redox potential and to an increase of the molecular acidity (as expressed in a reduction of the pKa value for the first protonation step). Furthermore, calculations of solubility in water indicate that some of the studied derivatives have adequate solubility for flow battery applications. Based on an analysis of the physico-chemical properties of the 156 studied compounds, we down-select five molecules with carbonyl- and nitro-based functional groups, whose parameters are especially promising for potential application as negative redox-active material inorganic flow batteries.

Download Full-text

Experimental and Physico-Chemical Comparison of ZnO Nanoparticles’ Activity for Photocatalytic Applications in Wastewater Treatment

Catalysts ◽

10.3390/catal11060678 ◽

2021 ◽

Vol 11 (6) ◽

pp. 678

Author(s):

Stefano Alberti ◽

Irene Basciu ◽

Marco Vocciante ◽

Maurizio Ferretti

Keyword(s):

Wastewater Treatment ◽

Zno Nanoparticles ◽

Energy Dispersive Spectrometer ◽

Chemical Properties ◽

X Ray Diffraction ◽

Commercial Sample ◽

Synthetic Process ◽

Physico Chemical ◽

Photocatalytic Applications ◽

Reflectance Measurements

In this contribution, the photoactivity upon activation by simulated sunlight of zinc oxide (ZnO) obtained from two different synthetic pathways (Acetate and Nitrate) is investigated for water purification. Different reagents and processes were exploited to obtain ZnO nanoparticles. Products have been characterized by means of X-Ray Diffraction, Scanning Electron Microscopy along with Energy Dispersive Spectrometer, Dynamic Light Scattering, and Diffuse Reflectance Measurements, to highlight the different outcomes ascribable to each synthesis. A comparison of characteristics and performances was also carried out with respect to commercial ZnO. Nanoparticles of this semiconductor can be obtained as aggregates with different degrees of purity, porosity, and shape, and their physical-chemical properties have been addressed to the specific use in wastewater treatment, testing their effectiveness on the photocatalytic degradation of methylene blue (MB) as a model pollutant. Excluding the commercial sample, experimental results evidenced a better photocatalytic behavior for the ZnO Nitrate sample annealed at 500 °C, which was found to be pure and stable in water, suggesting that ZnO could be effectively exploited as a heterogeneous photocatalyst for the degradation of emerging pollutants in water, provided that thermal treatment is included in the synthetic process.

Download Full-text

Physico-Chemical and Morphological Changes of Sayong Kaolinite Clay Treated with Sulphuric Acid for Enzyme Immobilization

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.832.589 ◽

2013 ◽

Vol 832 ◽

pp. 589-595 ◽

Cited By ~ 1

Author(s):

N.A. Edama ◽

A. Sulaiman ◽

K.H. Ku Hamid ◽

M.N. Muhd Rodhi ◽

Mohibah Musa ◽

...

Keyword(s):

Surface Area ◽

Sulphuric Acid ◽

Enzyme Immobilization ◽

Morphological Changes ◽

Chemical Properties ◽

X Ray Diffraction ◽

Kaolinite Clay ◽

X Ray ◽

Mineral Oxides ◽

Physico Chemical

This study analyzed the effects of sulphuric acid (H2SO4) treatment on pysico-chemical properties and morphological changes of clay obtained from Sg. Sayong, Perak. The clay was ground and sieved to <150μm and treated with different concentrations of H2SO4. The treatment was completed by refluxing the clay with different concentration of H2SO4 (1M, 5M and 10M ) at 100 °C for 4 hours and followed by calcination at 500 °C for 1 hour. The physic-chemical properties and morphological changes of the untreated and treated clay were compared using Surface Area Analyser, X-Ray Diffraction (XRD), Field Emission Scanning Electron Micrograph (FESEM), X-Ray Diffraction (XRD) and Fourier Transformed Infrared Spectroscopy (FTIR). The results showed that acid treatment of 5M increased the surface area from 25 m2/g to 75 m2/g and the pore volume increased from 0.1518 cc/g to 0.3546 cc/g. The nanopore size of the clay decreased from 24.8 nm to 19.4 nm after treated with acid. This can be explained due to the elimination of the exchangeable cations and generation of microporosity. The results of XRF showed SiO2 increased from 58.34% to 74.52% and Al2O3 reduced from 34.6% to 18.31%. The mineral oxides such as Fe2O3, MgO, CaO, K2O and TiO2 also reduced. This concluded that H2SO4 treatment has led to significant removal of octahedral Al3+, Fe3+ cations and other impurities. In conclusion, this study showed the physico-chemical properties and morphology of Sayong clay were improved once treated with H2SO4 and therefore suggests better supporting material for enzyme immobilization.

Download Full-text

Albumen-mediated Green Synthesis of ZnFe2O4 Nanoparticles and Their Physico-Chemical Properties

Jordan Journal of Physics ◽

10.47011/14.5.6 ◽

2021 ◽

Vol 14 (5) ◽

pp. 445-449

Keyword(s):

Zinc Ferrite ◽

Single Phase ◽

Chemical Properties ◽

Synthesis Process ◽

X Ray Diffraction ◽

Scanning Microscope ◽

Physico Chemical ◽

Znfe2o4 Nanoparticles ◽

Photoluminescence Studies ◽

Combustion Technique

Abstract: Spinel ferrites with general formula AB2O4 possess charming magnetic and electrical properties owing to their thermal and chemical steadfastness. Spinel zinc ferrite (ZnFe2O4) nanoparticles have attracted massive attention due to their unusual amalgamation of properties, especially magnetic properties, where these properties are equipped as suitable candidates in the field of electronics. Here, a simple self-combustion technique is made with the assistance of albumen to synthesize nanocrystalline zinc ferrite (ZnFe2O4) particles. The egg white (albumen) that is used in the synthesis process plays the fuel role in the process of combustion. The results of the powder X-ray diffraction (PXRD) and Fourier Transform Infrared Spectroscopy (FTIR) suggested that the synthesized nanoparticles are of single phase and show spinel structure. The photoluminescence studies reported a doublet peak at around 360-380 nm. The functional groups present in the synthesized nanoparticles were revealed from FTIR data. EDX findings give an account of the percentage composition of the elements Fe, Zn and O present in the synthesized sample. High-resolution Scanning Microscope (HRSEM) reveals the agglomerated coalescence nature of ferrite nanoparticles. Keywords: Ferrite, PXRD, FTIR, HRSEM, EDX Albumen.

Download Full-text

Controllable synthesis of pomelo peel-based aerogel and its application in adsorption of oil/organic pollutants

Royal Society Open Science ◽

10.1098/rsos.181823 ◽

2019 ◽

Vol 6 (2) ◽

pp. 181823 ◽

Cited By ~ 3

Author(s):

Guangyu Shi ◽

Yizhu Qian ◽

Fengzhi Tan ◽

Weijie Cai ◽

Yuan Li ◽

...

Keyword(s):

High Speed ◽

Chemical Properties ◽

Absorption Capacity ◽

High Porosity ◽

X Ray Diffraction ◽

Water Separation ◽

Physico Chemical ◽

Wide Range ◽

Oil Water Separation ◽

Oil Water

Oil/water separation is a field of high significance as it might efficiently resolve the contamination of industrial oily wastewater and other oil/water pollution. In this paper, an environmentally-friendly hydrophobic aerogel with high porosity and low density was successfully synthesized with renewable pomelo peels (PPs) as precursors. Typically, a series of sponge aerogels (HPSA-0, HPSA-1 and HPSA-2) were facilely prepared via high-speed dispersion, freeze-drying and silanization with methyltrimethoxysilane. Indeed, the physical properties of aerogel such as density and pore diameter could be tailored by different additives (filter paper fibre and polyvinyl alcohol). Hence, their physico-chemical properties including internal morphology and chemical structure were characterized in detail by Fourier transform infrared, Brunauer–Emmett–Teller, X-ray diffraction, scanning electron microscope, Thermal gravimetric analyzer (TG) etc. Moreover, the adsorption capacity was further determined and the results revealed that the PP-based aerogels presented excellent adsorption performance for a wide range of oil products and/or organic solvents (crude oil 49.8 g g −1 , soya bean oil 62.3 g g −1 , chloroform 71.3 g g −1 etc.). The corresponding cyclic tests showed the absorption capacity decreased slightly from 94.66% to 93.82% after 10 consecutive cycles, indicating a high recyclability.

Download Full-text