The synthesis and use of new amic acid extractants for the selective extraction of Cu(II),Ni(II) and Co(II) from other base metal ions in acidic medium

The liquid–liquid extraction of rare earth metal ions (scandium (Sc3+), yttrium (Y3+) and the lanthanides (La3+, Nd3+, Eu3+ and Dy3+)) was investigated using N-[N,N-di(2-ethylhexyl)aminocarbonylmethyl]glycine (D2EHAG).

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Revisiting the passivation of stainless steels and other passive CRAs

Matériaux & Techniques ◽

10.1051/mattech/2018020 ◽

2018 ◽

Vol 106 (1) ◽

pp. 107 ◽

Cited By ~ 3

Author(s):

Jean- Louis Crolet

Keyword(s):

Electrical Conductivity ◽

Metal Ions ◽

Base Metal ◽

Stainless Steels ◽

Electronic Conductivity ◽

Transport Processes ◽

General Knowledge ◽

Inorganic Polymers ◽

Faraday Cage

All that was said so far about passivity and passivation was indeed based on electrochemical prejudgments, and all based on unverified postulates. However, due the authors’ fame and for lack of anything better, the great many contradictions were carefully ignored. However, when resuming from raw experimental facts and the present general knowledge, it now appears that passivation always begins by the precipitation of a metallic hydroxide gel. Therefore, all the protectiveness mechanisms already known for porous corrosion layers apply, so that this outstanding protectiveness is indeed governed by the chemistry of transport processes throughout the entrapped water. For Al type passivation, the base metal ions only have deep and complete electronic shells, which precludes any electronic conductivity. Then protectiveness can only arise from gel thickening and densification. For Fe type passivation, an incomplete shell of superficial 3d electrons allows an early metallic or semimetallic conductivity in the gel skeleton, at the onset of the very first perfectly ordered inorganic polymers (- MII-O-MIII-O-)n. Then all depends on the acquisition, maintenance or loss of a sufficient electrical conductivity in this Faraday cage. But for both types of passive layers, all the known features can be explained by the chemistry of transport processes, with neither exception nor contradiction.

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Why do zeolites induce an unprecedented electronic state on exchanged metal ions?

Physical Chemistry Chemical Physics ◽

10.1039/c7cp02669b ◽

2017 ◽

Vol 19 (36) ◽

pp. 25105-25114 ◽

Cited By ~ 5

Author(s):

Akira Oda ◽

Takahiro Ohkubo ◽

Takashi Yumura ◽

Hisayoshi Kobayashi ◽

Yasushige Kuroda

Keyword(s):

Metal Ions ◽

Electronic State ◽

Base Metal ◽

Metal Ion ◽

High Efficiency ◽

Lewis Base ◽

Mfi Zeolite ◽

Adsorption Processes ◽

Exact Position

Understanding the exact position and the detailed role of the Al array in zeolites is essential for elucidating the origin of unique properties and for designing zeolite materials with high efficiency in catalytic and adsorption processes. In this work, we advanced pivotal roles of Lewis base–metal ion bifunctionality caused by Al atoms arrayed circumferentially in the MFI-zeolite pores.

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Selective extraction of metal ions associated with humic acids

Talanta ◽

10.1016/0039-9140(82)80050-7 ◽

1982 ◽

Vol 29 (9) ◽

pp. 743-749 ◽

Cited By ~ 36

Author(s):

J. Slavek ◽

J. Wold ◽

W.F. Pickering

Keyword(s):

Metal Ions ◽

Humic Acids ◽

Selective Extraction

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Selective extraction of trace metals associated with hydrous aluminum oxides

Canadian Journal of Chemistry ◽

10.1139/v87-168 ◽

1987 ◽

Vol 65 (5) ◽

pp. 984-989 ◽

Cited By ~ 7

Author(s):

Janece Slavek ◽

William Frederick Pickering

Keyword(s):

Metal Ions ◽

Selective Extraction ◽

Metal Species ◽

Initial Surface ◽

Aluminum Oxides ◽

Hydrous Oxides ◽

Soil Sediment ◽

Trace Metal Content ◽

Chemical Solutions ◽

The Relationship

In soil/sediment analysis, subdivision of trace metal content into different categories is usually based on selective extraction schemes. To assess the disposition of metal ions bound to aluminum hydrous oxides in such schemes, suspensions of Al(OH)3gel, gibbsite, or alumina were loaded with up to 5 μ mol of Cu, Pb, Cd, or Zn ions prior to being extracted for 24 h with one of fifteen different chemical solutions. The percentage of sorbed ion retrieved varied along the reagent sequence: NaCl, CaCl2 < MgCl2, NH4NO3 < CH3COONH4, Na citrate, Na4P2O7 < EDTA, DTPA < CH3COOH, H2C2O4, HCl, HNO3. In each system, the recovery value varied with the initial surface loading (a function of sorption pH) and reflected changes in metal species form, e.g., bonded M2+, (MOH+), M(OH)2. With low loading levels up to 40% was displaced by salt solutions; with 1 to 2 μ mol sorbed, as little as 10% was displaced by acids or complex formers but this increased to ~90% with higher loadings. The relationship between sorption pH, amount sorbed, and extraction value was complex, and since in selective extraction schemes classification is based on recovery values, changes in initial retention parameters (e.g. system pH) lead to varying fractions of the different metal ions being classified as "ion exchangeable", "chemisorbed", and "incorporated in the lattice".

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Synthesis, Structure and Characterization of New Amic Acid Derivatives of 3-Amino-1,2,4-Triazole and Their Complexes with Some Metal Ions

Chemistry for Sustainable Development ◽

10.1007/978-90-481-8650-1_7 ◽

2011 ◽

pp. 103-119

Author(s):

Ahlam J. Abdulghani ◽

Suad M. Sahan

Keyword(s):

Metal Ions ◽

Amic Acid ◽

Derivatives Of

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Changes in aggregate stability and associated organic matter properties after direct drilling and ploughing on some Australian soils

Soil Research ◽

10.1071/sr9800027 ◽

1980 ◽

Vol 18 (1) ◽

pp. 27 ◽

Cited By ~ 35

Author(s):

AP Hamblin

Keyword(s):

Metal Ions ◽

Aggregate Stability ◽

Selective Extraction ◽

Continuous Cropping ◽

Neutral Salt ◽

Structural Improvement ◽

Trivalent Metal Ions ◽

Direct Drilling ◽

The Stability ◽

Humic Fractions

After 3-8 years' continuous cropping with conventional cultivation and direct drilling, five Australian soils were examined for changes in structural stability attributable to tillage methods. Some increase in organic carbon was found in four direct drilled soils, and the proportion of carbon in the greater than 2 �m fractions was also higher in these soils after short ultrasonic treatment. Direct drilled soils had significantly greater stability with at least one of the stability tests used, but no soil showed consistently greater stability to five different tests. One direct drilled soil was more stable than its ploughed equivalent after alkaline and neutral salt extraction of metal ions and associated humic substances. One direct drilled soil was more dispersed by polysaccharide extraction. Three direct drilled soils retained greater stability after selective extraction of trivalent metal ions complexed to humic fractions. Structural improvement takes place in Australian soils after several years of direct drilling, but may be at a slower rate and to a lesser extent than has been reported for wetter environments.

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