Anna Parus

Removal of Copper(II) from Chloride Solutions using Hydrophobic Pyridyl Ketone Oximes

Abstract: The model oximes of 1‐(2‐pyridyl)undecane‐1‐one (2PC10), 1‐(2‐pyridyl)tridecane‐1‐one (2PC12) and 1‐(4‐pyridyl)tridecane‐1‐one (4PC12) were synthesized and used for copper(II) extraction from chloride solutions. The behavior of these ligands towards copper(II) extraction was investigated for different experimental conditions with a particular emphasis on the influence of the concentrations of copper ions, chloride ions, and ligand. The obtained results indicated the ability of pyridylketoximes to extract copper(II) from chloride solutions. 2‐Pyridyl ketone oximes are stronger extractants of copper than 4‐pyridyl ketone oximes. Copper can be effectively stripped by water or diluted sulfuric acid.

Solvent Extraction of Iron(III) From Chloride Solutions in the Presence of Copper(II) and Zinc(II) Using Hydrophobic Pyridyl Ketoximes

In this work, oximes of 1-(2-pyridyl)tridekane-1-one and 1-(4-pyridyl)tridecane-1-one were used as model hydrophobic extractants for iron(III) from a chloride media. Both studied pyridyl ketoximes have the ability to extract iron(III) from chloride solutions. The highest degree of iron(III) extraction was observed for 1-(2-pyridyl)tridecane-1-one oxime. During extraction with 4-pyridyl ketoxime, a precipitated complex was observed, which has a disadvantageous effect for the extraction process. Iron(III) could be effectively stripped by 1% HCl from organic solution after extraction. Selectivity extractions from multielemental aqueous solutions containing iron(III) using 2- and 4-pyridyl ketoximes were also studied. The highest extraction percentage and good selectivity was observed for Cu2+ from a solution containing 1.0 M Cl− with 1-(2-pyridyl)tridecane-1-one oxime. A scheme of separation of particular metal ions from mulielemental aqueous solutions was also proposed. The separation of metal ions is possible in three stages of extraction.

Zinc(II) Ions Removal from Chloride Solutions by Hydrophobic Alkyl-Pyridyl Ketoximes

The aim of this work was to examine the influence of the concentration of chloride, nitrate, perchlorate, and zinc(II) ions in the extraction process using synthesized hydrophobic 2-pyridyl ketoximes. Results indicated that oximes could extract zinc(II) ions from chloride solutions and that the extraction depended on ligand and chloride ion concentrations. A maximum extraction was observed at 1.0–1.5 M Cl- and at higher chloride solutions the complex-forming power of 2-pyridyl ketoximes slowly decreased. Zinc(II) ions were effectively stripped from the loaded organic phase with water or ammonia solutions in two stages. The regenerated oximes could yet be used again in the extraction of zinc(II) ions and the reagents could be able to extract solutions with similar results as before. The current study shows that 2-pyridyl ketoximes can be used to extract zinc(II) ions from concentrated chloride solutions and that the separation of copper(II) ions from multielemental solutions is possible.

Pyridylketoximes with Branched Alkyl Chain as Extractants of Copper(II) Ions from Chloride Solutions

The present work describes fundamental studies of extractive copper(II) ions removal from chloride media with 2-, 3-, and 4- pyridylketoximes containing 2-ethylhexyl chain. The effect of different variables on the extraction of copper(II) ions such as the concentration of chloride ions, hydrochloric acid, and ligand has been investigated. The results indicate that the extraction ability of the pyridineketoximes towards copper(II) ions depends significantly on the position of oxime group in the pyridine ring. The oxime of 3-ethyl-1-(2-pyridyl)heptan-1-one was determined as the strongest extractant of the tested oximes and metal stripping was possible by the sodium oxalate with 0.2% addition of sulfuric acid. However, the copper(II) complexes with 3-pyridylketxime reextrcation could be effectively done using water or ammonium hydroxides. The oxime of 3-ethyl-1-(4-pyridyl)heptan-1-one formed a stable emulsion during mixing with chloride solution.

Copper(II) ions’ removal from aqueous solution using green horse-chestnut shell as a low-cost adsorbent

ABSTRACT The adsorption of copper(II) ions from aqueous solutions by the green horse-chestnut shell was studied in a batch adsorption system. It was determined how the parameters of the adsorption process, such as time, pH, copper(II) ions concentration and sorbent dose, influence the effectiveness of copper(II) ions’ removal. The adsorption process was fast and equilibrium was established about 10 min, and near 95–97% of Cu(II) ions were removed from aqueous solution. Maximum copper(II) ions’ adsorption occurred at around pH 5. The adsorption kinetics are also described, using pseudo-first-order model and pseudo-second-order model of type 1 and 2. A comparison of the kinetics models on the overall adsorption rate showed that the adsorption system was best described by the pseudo-second-order model of type 1 (r2 = 0.999) for all initial concentrations. Another key part of this study was the use of the Freundlich model to determine the adsorption isotherm and the experimental data were in strong correspondence with this model.

Impact of O-alkyl-pyridineamidoximes on the soil environment

Pyridine derivatives such as oximes and amidoximes are widely used in pharmaceutical, analytical and coordination chemistry. Increasing interest in this group of compounds as well as their complexing properties and surface activity resulted in their introduction into the environment and change of the ecosystem functioning. Based on this phenomenon, the evaluation of impact O-alkyl-pyridineamidoximes on the soil environment was determined by analysis of changes of metal mobility in soil and plant seed germination. The obtained results indicate that O-propyl-pyridineamidoximes may change the mobility of metals in soil and influence the germination and development of plants. The introduction of these compounds to soil resulted in the reduction of metal (Cu, Pb, Fe) mobility in the soil matrix. This effect resulted in the retention of metals in the soil and inhibition of their mobility. This phenomenon suggests the possibility of using the analyzed compounds in the remediation process as a stabilizing factor. Pyridineamidoximes at a concentration below 100 mg/kg of soil did not influence the seed germination and plant development.

Esterquat herbicidal ionic liquids (HILs) with two different herbicides: evaluation of activity and phytotoxicity

Herbicidal ionic liquids (HILs) constitute a new concept in crop protection products. Their main advantage is the potential to combine the efficiency of traditional herbicides with low vapour pressure and adjustable water solubility which leads to improved environmental safety in the agricultural sector. Among many strategies to obtain new HILs, esterquats seem to be well suited for modification since both the cation and anion may be constituents of herbicides. In the framework of this study 16 new esterquat HILs were synthetized based on standard herbicides: 2,4-D, MCPA, MCPP, 4-CPA, Clopyralid and Dicamba. Germination tests performed on agricultural soil using cornflower indicated the best two HILs. Furthermore, analysis of the toxicological effects of HILs on wheat plants revealed an additional advantage of the two selected HILs. The glutathione (GSH) content and glutathione S-transferase (GST) activity showed a lower oxidative stress level in wheat plants treated with examined HILs, respectively, in comparison to a mixture of reference compounds. Finally the Ames test was applied in order to analyse the mutagenic activity of the two selected HILs.