High Molecular Weight Amines Research Articles

Soil Metabolism of the Herbicide Rimsulfuron under Laboratory and Field Conditions

Procedures were developed for soil analysis of rimsulfuron and its metabolites by means of GC-ECD, GC-FPD and GC-MS with a detection limit of 1 mu g of rimsulfuron equivalents per kilogram of dry soil, after purification of the soil extracts by TLC. Soil containing an exaggerated rimsulfuron concentration was incubated in the laboratory, in order to adjust the analytical procedures. To evaluate the role of different manuring managements, rimsulfuron was applied postemergence (10 g ha(-1) on a corn field in 1994 and 1995) on plots treated with (1) green manure, pig slurry applied in (2) November and (3) March, and cow manure applied in (4) November and (5) March and (6) untreated control plots without organic fertilizer. Neither rimsulfuron nor its metabolites were detected at soil depths lower than 8 cm. The results show that manure managements prolong rimsulfuron half-life in the 0-8 cm surface soil layer from a minimum of 14 days (control) to a maximum of 46 days (pig slurry in March). At corn harvest, rimsulfuron and its metabolites were not detected in soil. Similar soil degradation pathways were observed in the field as in the laboratory. N-(4,6-Dimethoxypyrimidin-2-yl)-N-[3-(ethylsulfonyl)-2-pyridinyl]urea 2 was a transient soil degradation product. N-[3-(ethylsulfonyl)-2-pyridinyl]-4,6-dimethoxy-2-pyrimidineamine 3 attained a maximum soil concentration after 20 days of incubation and then progressively disappeared and could not be detected after 40 days. The high-molecular weight amine 3 did not accumulate in soil, eliminating the concern for potential formation of nitroso amino compounds. 2-Hydroxy-3-(ethylsulfonyl)pyridine 4 became the major rimsulfuron soil degradation product. The soil concentrations increased and attained a maximum after 40 days of incubation and then decreased; its isomerization into 2-pyridone, followed by hydrolysis, could transform it into low molecular weight nontoxic products. The concentrations of 2-amino-4,6-dimethoxypyrimidine 5 were somewhat lower than those of compound 4.

Liquid-liquid extraction of tungsten(VI) from hydrochloric acid solutions by neutral organophosphorus compounds and high molecular weight amines

The extraction of tungsten(VI) from hydrochloric acid solutions by neutral organophosphorus compounds (tributyl phosphate, TBP, and trioctyl phosphine oxide, TOPO), and high molecular weight amines (trioctylamine, TOA, R 3N, and trioctylmethylammonium chloride, TOMAC, R 3R′NCl) in benzene was investigated in the presence of tartaric acid under various conditions. As a result, it was found that the extraction efficiency for tungsten(VI) of TBP, TOPO, TOA and TOMAC is in the order TOPO ⪢ TOMAC > TOA > TBP. The extraction efficiencies are lowered by increasing the amount of tartaric acid, although the presence of tartaric acid prevents the precipitation of tungsten salts. The distribution coefficients for TBP, TOPO, TOA and TOMAC rise steeply as the aqueous acidity is increased to a maximum at initial hydrochloric acid concentrations of 9–9.5, 6–6.5, 7–8 and 8 mol dm −3, respectively, and then falls at higher acidity. Based on the above, the equilibrium equations for the extraction of tungsten(VI) from hydrochloric acid solutions by TBP, TOPO, TOA and TOMAC are proposed as follows: WO 2Cl 2(a) + 2TBP(o) ⇌ WO 2Cl 2·2TBP(o) WO 2Cl 2(a) + 2TOPO(o) ⇌ WO 2Cl 2·2TOPO(o) WO 2Cl 2(a) + R 3NHCl(o) ⇌ R 3NHWO 2Cl 3(o) and: WO 2Cl 3(a) + R 3R′NCl(o) ⇌ R 3R′NWO 2Cl 3(o) + Cl −(a) where (a) and (o) represent aqueous and organic phases, respectively. These equations were confirmed by infrared spectra.

高分子量アミンによる塩酸溶液からのリテニウム（ＩＩＩ）の抽出

The extraction of ruthenium (III) from hydrochloric acid solutions has been investigated by using high molecular-weight amines under various conditions.The extraction isotherm shows a shape analogous, which has a minimum value at 1.5-2 mol dm-3 initial aqueous hydrochloric acid solution. Hence, it is suggested that the extraction species varies in low acidity (≤1.5 mol dm-3 HC1) and higher acidity (≥1.5 mol dm-3 HC1). The order of the extractability of amines, with the exception of BDDA, TOA, CODA and CDDA, is quaternary ammonium compound>>tertiary amine>secondary amine, and the extractability is promoted by substitution of benzyl (electron donor) group.Stoichiometric composition of the DOA and TOA complexes formed in the organic phase are deduced to be R2NH2Ru (OH) 2 Cl2·3H2O at low acidity and R2NH·2RuOCl2 2H2O at higher acidity and R3NHRu (OH) 2 Cl2·0.5R3NHCl·2H2O at low acidity and R3NHRu0Cl2·R3NHCl·H2O at higher acidity, respectively.In the examination of diluents effects, it is found that nitorobenzene is most effective for the extraction of Ru (III) with TOA.The distribution ratios in the extraction with DOA and TOA decrease with increasing temperature.

Extraction of Mn(II), Co(II), Cr(III) and Fe(III) from succinic acid medium by high molecular weight amines

The extraction behavior of Mn(II), Co(II), Cr(III) and Fe(III) has been studied in high molecular weight amines from succinic acid medium. The effect of different variables, like, type of amine, effect of pretreatment of amine with various acids, type of diluent and concentration of metal, succinate, hydrogen ions and amine, has been investigated. Extraction of Cr(III) and Fe(III) species is proposed and some binary separations achieved.

Liquid-Liquid Extraction of Trace Level Niobium and Tantalum by Trioctylamine

Studies on the liquid-liquid extraction(LLX) behavior of trace level niobium and tantalum, 95Nb and l82Ta, in HF, HCl, HNO3 and H2SO4 acid media with high molecular weight amine, trioctylamine, under different experimental conditions revealed that the extraction of tantalum is always higher than that of niobium, whatever be the acid or acidity in the aqueous phase. At optimal conditions, quantitative extraction of tantalum and its complete decontamination from niobium has been achieved in HCl and HNO3 media. In HF and H2SO4 media, the coextraction of niobium with tantalum can not, however, be avoided completely, because it has comparatively more affinities for fluoro- or sulfato-complex formation in the respective acid media. The purity and the extents of separation of the tracers by the liquid anion exchanger at different stages have been verified by means of γ-ray spectroscopy.

Solvent Extraction of Cerium(III) with High Molecular Weight Amines

Solvent Extraction of Cerium(III) with High Molecular Weight Amines

Selective removal of metals from waste streams

Abstract Copper, chromium, nickel, and zinc are frequently found in high concentrations in industrial waste water and can be removed by precipitation. Typical precipitation processes do not allow each metal to be precipitated separately, and hence selective metal recovery is not possible. It is desirable to recover each metal separately to allow recycling of metals and to satisfy waste minimization requirements. Chelation can be utilized to selectively remove metals from aqueous solution, since chelation can be controlled by pH. A study has been undertaken to determine the pH optima for removal of copper, nickel, and zinc by chelation with dithiozone. A similar study will be initiated to determine the pH optimum for removal of chromium by chelation with Aliquat 336, a high molecular weight amine. Percent extraction of metal was measured as a function of metal solution pH. Two dithiozone solvents, chloroform and carbon tetrachloride, were investigated. The preliminary results indicate that the optimum pH for extraction of copper with dithiozone—chloroform solution is near pH 3. As a solvent, chloroform allows more copper extraction than carbon tetrachloride. Carbon tetrachloride was rejected as a solvent due to the low solubility of dithiozone in carbon tetrachloride. The chelation reaction must be performed in a pH-buffered solution to maintain a constant pH. The results of this study will be utilized to design a process to selectively recover metals from industrial waste water.

Extraction and separation of uranium and lead with liquid anion-exchangers

A method is proposed for the extraction and separation of microgram amounts of uranium(VI) and lead(II) from sodium salicylate solution with high molecular-weight amines such as Aliquat 336, TOA, TIOA, Amberlite LA-1 or Amberlite LA-2 dissolved in xylene. From a critical study of pH, salicylate concentration, amine concentration, diluent and period of equilibration, the optimum conditions were identified. The method permits separation of uranium and lead from binary mixtures with metal ions commonly associated with them, the determination of uranium, and of lead in air samples.

Liquid-liquid extraction of rhenium (VII) from hydrochloric acid solutions by neutral organophosphorus compounds and high molecular weight amines

The extraction of rhenium (VII) from hydrochloric acid solutions has been investigated using two neutral organophosphorus compounds - tributyl phosphate (TBP) and trioctyl phosphine oxide (TOPO) - and two high molecular weight amines - trioctylamine (TOA) and trioctylmethylammonium chloride (TOMAC). As a result, it was found that the extraction equilibria for TBP, TOPO, TOA and TOMAC can be expressed as follows: ReO 3CI org + nS org ⇋ ReO 3Cl nS org where n=4 and 2 for S = TBP and TOPO, respectively; HReO 4 aq + R 3NHCl org ⇋R 3NH 2ReO 4Cl org for TOA; and ReO 4 aq − + R 3R′NCl org ⇋ R 3R′NReO 4org + Cl − aq for TOMAC. In these extraction systems, the rhenium (VII) extraction efficiency follows the order TOA > TOMAC > TOPO > TBP at low aqueous acidity and TOMAC > TOA > TOPO > TBP at higher acidity.

Reversed Phase Thin Layer Chromatographic Separations of Some Elements of the First Transition Series Using High Molecular Weight Amines

Abstract Reversed phase thin layer chromatographic behavior of metal ions of the first transition series has been investigated on silica gel plates coated with different high molecular weight amines using citric acid as eluant. The effect of type of amine and concentration of amine and citric acid on hRf values has been studied. Some binary and ternary separations of topical interest were achieved using 3.0% Primene JM-T and 0.030 M citric acid.

Selective removal of metals from waste streams

Copper, chromium, nickel, and zinc are frequently found in high concentrations in industrial waste water and can be removed by precipitation. Typical precipitation processes do not allow each metal to be precipitated separately, and hence selective metal recovery is not possible. It is desirable to recover each metal separately to allow recycling of metals and to satisfy waste minimization requirements. Chelation can be utilized to selectively remove metals from aqueous solution, since chelation can be controlled by pH. A study has been undertaken to determine the pH optima for removal of copper, nickel, and zinc by chelation with dithiozone. A similar study will be initiated to determine the pH optimum for removal of chromium by chelation with Aliquat 336, a high molecular weight amine. Percent extraction of metal was measured as a function of metal solution pH. Two dithiozone solvents, chloroform and carbon tetrachloride, were investigated. The preliminary results indicate that the optimum pH for extraction of copper with dithiozone—chloroform solution is near pH 3. As a solvent, chloroform allows more copper extraction than carbon tetrachloride. Carbon tetrachloride was rejected as a solvent due to the low solubility of dithiozone in carbon tetrachloride. The chelation reaction must be performed in a pH-buffered solution to maintain a constant pH. The results of this study will be utilized to design a process to selectively recover metals from industrial waste water.

Extraction of rare earth elements by primary high molecular weight amines from hydrochloric acid solutions

Extraction of trivalent lanthanides: La, Ce, Nd, Eu, Tb, Tm, Yb by primary high molecular weight amines from 0.5–3M hydrochloric acid solutions, containing complex-forming agent potassium phosphotungstate /K10P2W17O61/ has been investigated. The effect of hydrochloric acid, potassium phosphotungstate and amine concentration, the length of primary amine alkyl chain, organic solvents nature and elements ionic radii on distribution coefficients have been studied. It has been established that the system can be used for group isolation and separation of rare earth elements.

Extraction of Ce(III), Gd(III) and Yb(III) from Citrate Medium by High Molecular Weight Amines

Abstract High molecular weight amines have been used for the extraction of citrate complexes of Ce(III), Gd(III) and Yb(III). The effect of different variables on extraction has been studied. The citrate species extracted in the organic phase have been proposed as [(RNH3 +)3] [M(Cit)2]3-.

Solvent extraction of some metals from aqueous solutions

The results for the extractions of divalent (manganese, cobalt, zinc and cadmium) and trivalent (gallium and indium) metals and hexavalent uranium from aqueous solutions by various extractants such as organophosphorus compounds (tributyl phosphate, trioctylphosphine oxide, di-(2-ethylhexyl)phosphoric acid and 2-ethylhexyl 2-ethylhexylphosphonic acid), sulfur-containing compound (dihexyl sulfoxide), high-molecular weight amines (trioctylamine and trioctylmethylammonium chloride) and 7-alkylated hydroxyquinoline (7-(5,5,7,7-tetramethyl-1-octen-3-yl)-8-hydroxyquinoline are discussed in the viewpoint of separation chemistry.

Isolation and HPLC determination of amines in wine

The isolation of the amines from wines for liquid chromatography was accomplished by either continuous extraction with Freon 11-methylene chloride or with butanol-methylene chloride. The former method gives high recoveries for high-molecular weight amines and the latter for low molecular weight amines. Amines were dansylated and detected with fluorescence and UV detectors. The methods were used to determine amine contents of wines from different countries. The identification of amines was based on UV spectra of dansylamides with a diode array detector.

Extraction of rare earth elements by high molecular weight amines from nitric acid solutions

Extraction of trivalent rare earth elements by a high molecular weight primary amine /decylamine/ from 0.5–3M nitric acid solutions, containing potassium phosphotungstate /K10P2W17O61/, has been investigated. The effect of nitric acid and potassium phosphotungstate concentration of the organic solvent, and lanthanides ionic radii upon distribution coefficients has been studied. It has been established that decylamine solutions in chloroform can be used for the group isolation of rare earth elements and for their separation.

Thermal decomposition of the solvent-extracted metal complexes with high molecular weight amines

Organic solutions from the extractions of divalent manganese, cobalt, copper and zinc, trivalent gallium, indium and thallium, tetravalent vanadium and zirconium, and hexavalent uranium and molybdenum with trioctylamine (TOA, R 3N) and trioctylmethylammonium chloride (TOMAC, R 3R′NCl) in benzene were heated in vacua to prepare benzene-free complexes. The resulting complexes were examined by thermogravimetry and differential thermal analysis under an atmosphere of nitrogen, and their thermally decomposed products, such as volatile matters and residues, by gas chromatography, X-ray diffraction and infrared spectroscopy. Consequently, the thermal decomposition process of these complexes is discussed and the structure of the complexes is proposed on the basis of the results obtained.

Extraction of tetravalent berkelium by high molecular weight amines in the presence of heteropolyanions

Extraction of tetravalent berkelium by high molecular weight amines and quaternary ammonium base from nitric acid solutions containing potassium phosphotungstate, K10P2W17O61, and potassium bromate as an oxidant has been studied. Tetravalent berkelium is quantitatively extracted in the presence of potassium phosphotungstate with all amines studied. The maximal extent of berkelium extraction is obtained in different acid concentration ranges depending on the nature of amine. Distribution coefficients as a function of acid concentration, extractant, potassium phosphotungstate were examined. The mechanism and stoichiometry of Bk/IV/ extraction has been investigated. Data obtained allowed us to work out extraction methods of separation and purification of berkelium from trivalent transplutonium and rare earths elements, and some fission products.

Studies on colour removal from bleach plant effluent of a kraft pulp mill

AbstractA comparative study for colour removal of pulp bleach plant effluent with three different decolorising agents: fly ash, high molecular weight amine (Kemamine T 1902D) and lime, showed 90% or more colour removal. Fly ash treatment offered a promising way for colour removal (94%); amine treatment yielded better colour removal than fly ash but had comparatively high cost. The large amount of lime needed to remove the colour beyond 90% restricts its use, since large‐scale equipment would be costly.

Determination of the heat change in solvent extraction of metals. The extraction of zinc (II) from hydrochloric acid solutions by high molecular weight amines in various organic solvents

AbstractThe heat change associated with the uptake of zinc (II) has been examined by using a twin type isoperibol calorimeter in the extraction of zinc (II) from hydrochloric acid solutions by trioctylamine hydrochloride (TOAHCl) and trioctylmethyl‐ammonium chloride (TOMAC) in various organic solvents such as benzene, chlorobenzene, o‐dichlorobenzene, toluene, m‐xylene, nitrobenzene, carbon tetrachloride and 1, 2‐dichloroethane. It was found that the dependence of apparent molar heat change (the value of the heat change detected with regard to the concentration of zinc (II) reacted) on the aqueous chloride concentration could be attributed to the change in the distribution of zinc (II) chloride species in the aqueous phase. Taking account of this fact, variable Y, which constitutes the sum of the change in enthalpies for the relevant steps in the extraction of zinc (II), except the transformation of ZnClj(2‐j)+ to ZnCl42‐, in the aqueous phase, is introduced. From the values of Y obtained, it is concluded that in the extraction by TOMAC, Y correlates with the solubility parameter of diluent, suggesting that the organic phases may be regarded as regular solutions, while in the extraction by TOAHCl, no clear‐cut relation holds between Y and the physico‐chemical constants of the diluent such as dipole moment, dielectric constant and solubility parameters.