Models for Association of Metal Ions with Heterogeneous Environmental Sorbents. 1. Complexation of Co(II) by Leonardite Humic Acid as a Function of pH and NaClO4 Concentration

1995 ◽  
Vol 29 (4) ◽  
pp. 951-959 ◽  
Author(s):  
John C. Westall ◽  
John D. Jones ◽  
Gary D. Turner ◽  
John M. Zachara
Keyword(s):  
Humic Acid ◽  
Metal Ions ◽  
Leonardite Humic Acid

Complexation of TbIII with size fractions of humic acid: evidence from luminescence sensitisation and anisotropy measurements

2007 ◽  
Vol 4 (3) ◽  
pp. 204 ◽  
Author(s):  
Jeremy Riggle ◽  
Ray von Wandruszka
Keyword(s):  
Humic Acid ◽  
Metal Ions ◽  
Fate And Transport ◽  
Humic Material ◽  
Size Fractions ◽  
Vis Spectroscopy ◽  
Good Energy ◽  
Trivalent Metal Ions ◽  
Luminescence Anisotropy ◽  
Leonardite Humic Acid

Environmental context. Organic ligands, especially those derived from humic acid (HA), play a major role in the fate and transport of metal ions in the environment. For the modelling of subsurface pollutant transport, it is important to understand which components of a heterogeneous humic material interact most strongly with multivalent cations. Abstract. The luminescence sensitisation and anisotropy characteristics of a series of TbIII complexes with a leonardite humic acid (LHA) were investigated in order to evaluate the interactions between the metal and different components of the humate. Ultrafiltration was used to separate LHA into six size fractions, which ranged from 500 Da to 0.2 μm, and were then used to form the TbIII complexes. Each fraction was first characterised by 13C NMR and UV-Vis spectroscopy, which showed that the smaller ones (<3 kDa) had a significantly lower aliphatic content than the larger ones. These smaller components were good energy donors, which could effectively sensitise TbIII luminescence. At the same time, the luminescence anisotropy of TbIII increased significantly when these LHA fractions were added, which indicated the formation of tightly bound complexes. In this sense, the smaller LHA fractions were comparable to ethylenediaminetetraacetate, although their effect was not as strong. In contrast, the larger LHA sizes had little or no influence on TbIII sensitisation or anisotropy. The results obtained suggest that the sizes and aliphatic content of humic polymers play a major role in their aqueous interactions with trivalent metal ions. Divalent metals are expected to behave in a similar way.

Biodegradation of phorate by bacterial strains in the presence of humic acid and metal ions

2021 ◽  
Author(s):  
Simranjeet Singh ◽  
Vijay Kumar ◽  
Amith G. Anil ◽  
Romina Romero ◽  
Praveen C. Ramamurthy ◽  
...  
Keyword(s):  
Humic Acid ◽  
Metal Ions ◽  
Bacterial Strains

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.

Humic Colloid Generation of Transuranic Elements in Groundwater and Their Migration Behaviour

1986 ◽  
Vol 84 ◽  
Author(s):  
J.I. Kim ◽  
G. Buckau ◽  
W. Zhuang
Keyword(s):  
Heavy Metal ◽  
Humic Acid ◽  
Organic Carbon ◽  
Dissolved Organic Carbon ◽  
Metal Ions ◽  
Fulvic Acid ◽  
Photoacoustic Spectroscopy ◽  
Heavy Metal Ions ◽  
Colloidal Form ◽  
Doc Concentration

AbstractThe generation of humic colloids of Am(III) has been investigated in Gorleben groundwaters containing different amounts of humic substances. Dissolved organic carbon (DOC) in these groundwaters consists mainly of humic acid and fulvic acid, which is present in a colloidal form through aggregation with trace heavy metal ions of groundwater constituents. Concentrations of these heavy metal ions are proportional to the DOC concentration. The generation of Am(III) pseudocolloids through geochemical interactions with humic colloids in different groundwaters is quantified by ultrafiltration as well as ultracentrifugation by the aid of radiometric concentration measurements. The speciation of dissolved Am(III) species in groundwaters is carried out by laser induced photoacoustic spectroscopy (LPAS).

Coagulation mechanisms of humic acid in metal ions solution under different pH conditions: A molecular dynamics simulation

2020 ◽  
Vol 702 ◽  
pp. 135072 ◽  
Author(s):  
Yuejie Ai ◽  
Chaofeng Zhao ◽  
Lu Sun ◽  
Xiangke Wang ◽  
Lijun Liang
Keyword(s):  
Molecular Dynamics ◽  
Humic Acid ◽  
Molecular Dynamics Simulation ◽  
Metal Ions ◽  
Dynamics Simulation ◽  
Ph Conditions

Effect of pH or Metal Ions on the Oil/Water Interfacial Behavior of Humic Acid Based Surfactant

Langmuir ◽  
2020 ◽  
Vol 36 (36) ◽  
pp. 10838-10845
Author(s):  
Xiaodong Lian ◽  
Shenglong Liao ◽  
Yipan Yang ◽  
Xiaogang Zhang ◽  
Yapei Wang
Keyword(s):  
Humic Acid ◽  
Metal Ions ◽  
Interfacial Behavior ◽  
Effect Of Ph ◽  
Oil Water

Adsorption of Heavy Metal Ions onto Insolubilized Humic Acid

1995 ◽  
Vol 171 (2) ◽  
pp. 490-494 ◽  
Author(s):  
Hideshi Seki ◽  
Akira Suzuki
Keyword(s):  
Heavy Metal ◽  
Humic Acid ◽  
Metal Ions ◽  
Heavy Metal Ions

scholarly journals Influence of Humic Acid Complexation with Metal Ions on Extracellular Electron Transfer Activity

2015 ◽  
Vol 5 (1) ◽  
Author(s):  
Shungui Zhou ◽  
Shanshan Chen ◽  
Yong Yuan ◽  
Qin Lu
Keyword(s):  
Electron Transfer ◽  
Humic Acid ◽  
Metal Ions ◽  
Extracellular Electron Transfer ◽  
Transfer Activity

Competition and complexation of heavy metal ions and humic acid on zeolitic MCM-22 and activated carbon

2008 ◽  
Vol 139 (3) ◽  
pp. 437-444 ◽  
Author(s):  
T. Terdkiatburana ◽  
Shaobin Wang ◽  
M.O. Tadé
Keyword(s):  
Heavy Metal ◽  
Activated Carbon ◽  
Humic Acid ◽  
Metal Ions ◽  
Heavy Metal Ions

Sorption Equilibrium of a Wide Spectrum of Organic Vapors in Leonardite Humic Acid:  Modeling of Experimental Data

2006 ◽  
Vol 40 (17) ◽  
pp. 5374-5379 ◽  
Author(s):  
Christian Niederer ◽  
Kai-Uwe Goss ◽  
René P. Schwarzenbach
Keyword(s):  
Experimental Data ◽  
Humic Acid ◽  
Wide Spectrum ◽  
Sorption Equilibrium ◽  
Organic Vapors ◽  
Leonardite Humic Acid
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