Interaction of Metal Cations with Functionalised Hydrocarbons in the Gas Phase: Further Experimental Evidence for Solvation of Metal Ions by the Hydrocarbon Chain

2016 ◽  
Vol 22 (2) ◽  
pp. 61-70 ◽  
Author(s):  
Nick A. van Huizen ◽  
Theo M. Luider ◽  
Karl J. Jobst ◽  
Johan K. Terlouw ◽  
John L. Holmes ◽  
...  
Keyword(s):  
Metal Ions ◽  
Experimental Evidence ◽  
Gas Phase ◽  
Metal Cations ◽  
Hydrocarbon Chain

Interaction of Metal Cations with Alkylnitriles in the Gas Phase: Solvation of Metal Ions by the Hydrocarbon Chain

2015 ◽  
Vol 21 (3) ◽  
pp. 579-587 ◽  
Author(s):  
Karl J. Jobst ◽  
Johan K. Terlouw ◽  
Theo Luider ◽  
Nick A. van Huizen ◽  
Peter C. Burgers
Keyword(s):  
Metal Ions ◽  
Gas Phase ◽  
Metal Cations ◽  
Hydrocarbon Chain

The effect of partial exchange of sulphonated macroporous styrene-divinylbenzene copolymers for different ions on their catalytic activity

1981 ◽  
Vol 46 (10) ◽  
pp. 2354-2363 ◽  
Author(s):  
Svatomír Kmošták ◽  
Karel Setínek
Keyword(s):  
Catalytic Activity ◽  
Transition Metal ◽  
Metal Ions ◽  
Gas Phase ◽  
Transition Metal Ions ◽  
Exchange Capacity ◽  
Total Exchange Capacity ◽  
Styrene Divinylbenzene ◽  
Na Ions ◽  
Type Of Transition

The catalytic activity of sulphonated macroporous styrene-divinylbenzene copolymers, the exchange capacity of which was neutralized from 30, 50 and 80% by Fe(III) ions and from 30% by Na ions and that of Wofatit Y-37 ion exchanger neutralized from 10% of its total exchange capacity by several transition metal ions and by sodium has been studied in isomerisation of cyclohexene and dehydration of 1-propanol in the gas phase at 130 °C. It was demonstrated that in both reactions transition metal ions exhibit additional effect to the expected neutralization of the polymer acid groups. In the case of cyclohexene isomerization, this effect depends on the degree of crosslinking of polymer mass of the catalyst. Such dependence has not been, however, observed in dehydration of 1-propanol. The type of transition metal ions did not exhibit any significant effect on the catalytic activity of the polymer catalysts studied.

scholarly journals Isolation of humic acid from oxidized lignite and complexation with metal cations

2017 ◽  
Vol 71 (4) ◽  
pp. 319-327
Author(s):  
Benjamin Catovic ◽  
Minela Sisic ◽  
Majda Srabovic ◽  
Melita Huremovic
Keyword(s):  
Humic Acid ◽  
Metal Ions ◽  
Humic Acids ◽  
Metal Binding ◽  
Base Material ◽  
Metal Cations ◽  
Biological Properties ◽  
Metal Nitrate ◽  
Chemical Difference ◽  
The Difference

Lignite is brown coal, which in its composition contains humic acids. Humic acids are produced by coal combustion, which leads to the enrichment of coal humic acids. Lignite, from the opet pit mine Sikulje, lignite ore ?Kreka?, Bosnia and Herzegovina, was fragmented and sieved to the appropriate size and used as a base material. The isolation of humic acid was carried out from pre-oxidized and dried lignite after which it was refined. Identification thus obtained humic acids was carried out by FTIR spectroscopy and its characterization of UV analysis which is determined by optical density of isolated humic acid and its complexation with metal cations. Data obtained by FTIR spectroscopic analysis of isolated humic acids show no significant structural and chemical difference in relation to the spectrum obtained for standard humic acids (Sigma Aldrich). UV analysis showed that isolated and standard humic acid have E4/E6 ratio in an appropriate range of 3?5, which indicates the presence of a large number of aliphatic structure. Based on the degree of humification was found that the isolated humic acids belong to the type B standard while humic acids belong to type A. The most important property of the humic substances is the ability to interact with the metal ions forming soluble or insoluble complexes which possess different chemical and biological properties and stability. The nature of the complex between humic acid and metal cation derived from the heterogeneous, polyelectric and polydispersive character humic acids that occurs due to the presence of a large number of functional groups. Complexation of humic acid is carried out with different concentrations of metal nitrate solutions and at different pH values. Different amounts of humic acids were used for the complexation. The amount of the free metal ions was measured with the ICP-OES methode. The data were also statistically analyzed with ANOVA. The results showed that increasing the pH reduces the concentration of metal ions adsorbed on humic acid and by increasing the concentrations and amounts of metal humic acid that power increases. On the basis of the difference in absorbance between metals and humic acids can be said that there is an interaction between the metal and the ligand and is based on absorbance values obtained can be determine the next set of metal binding to humic acids Pb>Zn>Ni>Cu.

scholarly journals PQQ-Aza-Crown Ether Complexes as Biomimetics for Lanthanide and Calcium Dependent Alcohol Dehydrogenases

2021 ◽  
Author(s):  
Violeta A. Vetsova ◽  
Katherine R. Fisher ◽  
Henning Lumpe ◽  
Alexander Schäfer ◽  
Erik K. Schneider ◽  
...  
Keyword(s):  
Metal Ions ◽  
Gas Phase ◽  
Ion Mobility ◽  
Paramagnetic Resonance ◽  
Calcium Dependent ◽  
Lower Charge ◽  
Crown Ether Complexes ◽  
Recent Group ◽  
Electron Paramagnetic

<div>Understanding the role of metal ions in biology can lead to the development of new catalysts for</div><div>several industrially important transformations. Lanthanides are the most recent group of metal ions</div><div>that have been shown to be important in biology i.e. - in quinone-dependent methanol</div><div>dehydrogenases (MDH). Here we evaluate a pyrroloquinoline quinone and 1-aza-15-crown-5 based</div><div>ligand platform as scaffold for Ca2+ , Ba2+ , La3+ and Lu3+ biomimetics of MDH and we evaluate the</div><div>importance of ligand design, charge, size, counterions and base for the alcohol oxidation reaction</div><div>using NMR spectroscopy. In addition, we report a new straightforward synthetic route (3 steps</div><div>instead of 11 and 33% instead of 0.6% yield) for biomimetic ligands based on PQQ. We show that</div><div>when studying biomimetics for MDH, larger metal ions and those with lower charge in this case</div><div>promote the dehydrogenation reaction more effectively and that this is likely an effect of the ligand</div><div>design which must be considered when studying biomimetics. To gain more information on the</div><div>structures and impact of counterions of the complexes, we performed collision induced dissociation</div><div>(CID) experiments and observe that the nitrates are more tightly bound than the triflates. To resolve</div><div>the structure of the complexes in the gas phase we combined DFT-calculations and ion mobility</div><div>measurements (IMS). Furthermore, we characterized the obtained complexes and reaction mixtures</div><div>using Electron Paramagnetic Resonance (EPR) spectroscopy and show the emergence of a quinone-</div><div>based radical during the reaction with substrate and base.</div>

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