Monometallic Salts Research Articles

Metal concentration and metal mass of metallicolous, non metallicolous and serpentine Noccaea caerulescens populations, cultivated in different growth media

Aims Evaluate the genetic and environmental variability of metal concentration and metal mass of Noccaea caerulescens, from metalliferous (MET), non metalliferous (NMET) and serpentine (SERP) soils. Methods 18 populations were cultivated in 18 different growth conditions, such as a soil mine tailing, soils amended with zinc (Zn), cadmium (Cd) and nickel (Ni) salts (in mixtures or in monometallic salts) and a hydroponic solution with two Zn concentrations. Results MET populations had Zn concentrations lower than NMET and SERP in the different soils but higher Cd mass (the product of aerial biomass and foliar metal concentration). SERP had the highest Ni concentration and Ni mass values. The addition of Cd or Ni to a Zn-contaminated soil significantly decreases Zn concentration. In hydroponics, MET and NMET had equivalent Zn concentrations but these were three times higher than those obtained in soil experiments. Zn mass of NMET was significantly lower than MET with the latter having Zn mass values largely above those obtained in mine soil. Conclusions Results showed a large heterogeneity of responses among populations depending on the substrate used, and it was not possible to correctly assign a single population to its accurate origin with only one experiment. Finally, data on metal concentration obtained in culture soils are closer to those in field soils than those from hydroponics so that they could give a more accurate information on the accumulating capacity of Noccaea caerulescens and its use in phytoextraction of metals in field conditions.

Monometallic salts derived from complex anions of group 10 metal ions with p-tolylsulfonyldithiocarbimate ligand: Synthesis, characterization and properties

New monometallic complex salts of the form X2[M(L)2] [M=Ni2+, X=(CH3)2NH2+(1); M=Ni2+, X=(CH3)4N+ (2); M=Ni2+, X=(C2H5)4N+(3); M=Ni2+, X=(C3H7)4N+(4); M=Ni2+; X=(C6H13)4N+) (5); M=Pd2+, X=(CH3)2NH2+(6); M=Pd2+, X=(C2H5)4N+(7); M=Pd2+, X=(C3H7)4N+(8); M=Pd2+, X=(C6H13)4N+ (9); M=Pt2+, X=(CH3)2NH2+(10); L=p-tolylsulfonyldithiocarbimate (CH3C6H4SO2NCS22−)] have been prepared and characterized by elemental analysis, IR, 1H and 13C NMR and UV–Vis spectroscopy; 1, 3, 4 and 5 by X-ray crystallography. In 1, 3, 4 and 5, the Ni atom is four coordinate with a square planar environment being bonded to four sulfur atoms from two bidentate ligands. All the salts are weakly conducting (σrt=10−7 to 10−14Scm−1) because of the lack of significant S···S intermolecular interactions between complex anions [M(L)2]2− in the solid state however, they show behavior of semiconductors in the temperature range 353–453K. All the Pd(II) and Pt(II) salts exhibited phtotolumeniscent emissions near visible region in solution at room temperature.

Studies on Metal‐Containing Co‐polyurethanes Based on Mono(hydroxyethoxyethyl)phthalate

Metal salts of mono(hydroxyethoxyethyl)phthalate [M(HEEP)2](M=ca2+ and Zn2+) were synthesized by the reaction of diethylene glycol, phthalic anhydride and metal acetates. Metal‐containing co‐polyurethanes (MCPUs) having ionic linkages in the main chain were synthesized by the polyaddition reaction of hexamethylene diisocyanate or tolylene 2,4‐diisocyanate with 1∶1 mixtures of [M(HEEP)2] and 1,5‐pentane diol (PD) by using di‐n‐butyltin dilaurate as a catalyst. The MCPUs were characterized by FT‐IR, 1H‐NMR, 13C‐NMR elemental analysis, solubility, viscosity and X‐ray diffraction. Thermal properties of the polymers were also studied using thermogravimetric analysis and differential scanning calorimetry. The MCPUs were soluble only in highly polar solvents. The thermogravimetric analysis of MCPUs showed that the metal ions influence the initial decomposition temperature and overall thermal stability.

Influence of the metallic precursor in the hydrogenation of tetralin over Pd–Pt supported zirconium doped mesoporous silica

Palladium–platinum supported on zirconium doped mesoporous silica catalysts have been prepared by incipient wetness impregnation with two different precursors: (i) a dinuclear precursor [PdPtCl2(μ-dppm)2] where dppm = Ph2PCH2PPh2; and (ii) PdCl2 and H2PtCl6·6H2O. The catalysts obtained with the bimetallic precursor show a much smaller metallic particle size than those prepared using monometallic precursors. The influence of the precursor in the hydrogenation of tetralin at high hydrogen pressure was studied. Both types of catalysts exhibit a good hydrogenation activity with a poor hydrogenolysis/ring opening activity. The type of precursor has a marked influence in the observed trans- to cis-decalin ratio being higher for catalysts prepared with monometallic precursors. Both types of catalysts show a good thiotolerance against dibenzothiophene, but the observed poisoning is more reversible in the case of catalysts prepared using monometallic precursors. A positive effect of the hydrogen pressure over the catalyst thiotolerance was observed, and using a P(H2) of 6 MPa, the catalyst with a 2 wt% PdPt prepared from monometallic salts was found to be very resistant to sulfur poisoning, with a tetralin conversion higher than 95% in the presence of 1375 ppm of DBT in the feed, at 588 K.

Studies on metal-containing copolyurethanes

Metal-containing copolyurethanes having ionic linkages in the main chain were synthesized by the polyaddition reaction of hexamethylene diisocyanate (HMDI) or toluene 2,4-diisocyanate (TDI) with 1:1 mixtures of divalent metal salts of mono(hydroxypentyl)phthalate, [M(HPP)] 2 (where M=Ca 2+, Cd 2+, Pb 2+ and Zn 2+), and diethylene glycol (DG) by using di- n-butyltin dilaurate (DBTDL) as catalyst. The prepared coployurethanes were characterized by FT-IR, 1H-NMR, 13C-NMR, elemental analysis, solubility, viscosity and X-ray diffraction studies. Thermal properties of the polymers were also studied by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The antibacterial activity of these polymers has also been investigated by agar diffusion method.

Metal accumulation and competitive ability in metallicolous and non-metallicolous Thlaspi caerulescens fed with different Zn salts

A non-metallicolous (NM) ecotype of Thlaspi caerulescens from Luxembourg and a metallicolous (M) ecotype from Prayon (E Belgium) are compared for growth and Zn, Mg and Ca accumulation in shoot in a pot experiment in six soil conditions with contrasting Zn availability. The soils were spiked with 2000 mg kg−1 Zn as monometallic salts of contrasting solubility. Both ecotypes were grown in pure and mixed culture in order to assess competitive ability. Both ecotypes had similar growth on all substrates except the one spiked with Zn-sulphate, where ecotype M grew better and had higher competitive ability than ecotype NM. Ecotype NM had higher Zn concentrations than M in all treatments and the difference varied with Zn availability, being largest with Zn-oxide (NM: 31 300 mg kg−1 Zn; M: 5900 mg kg−1 Zn). The results thus indicate that ecotype NM has constitutively higher Zn uptake capacity and may have a higher ability to obtain Zn from specific Zn salts. However, ecotype NM does not appear to be more efficient in obtaining Zn from little available forms. Mg concentration was also higher in ecotype NM. Zn mass per plant was higher in ecotype NM compared to ecotype M in all substrates except Zn-sulphate where the reverse was true. Accordingly, ecotype NM could prove to be a better phytoextractor of Zn for phytoremediation, except in substrates with low pH and high concentration of free Zn in the soil solution.

Thermal decomposition of energetic materials 79: Thermal, vibrational, and X-ray structural characterization of metal salts of mono- and di-anionic 5-nitraminotetrazole

The energetic alkali metal salts (Li +, Na +, K +, Rb +, Cs +) of the 5-nitraminotetrazole mono-anion(II) and di-anion(III) were synthesized and their properties compared with neutral 5-nitraminotetrazole(I). The decomposition temperatures by DSC follow the order (III)>(II)>(I), and for the salts of (III) Li +>Na +>K +>Rb +>Cs +. Both thermal stability trends are consistent with a major role played by the crystal lattice energy. Loss of H 2O is detected by TGA in cases where hydrates also form. The crystal and molecular structures of Cs(II) and Rb 3(III)(NCNNO 2)·H 2O were determined by X-ray diffraction. The latter compound is the first structural characterization of (III) and also contains the nitrocyanamide anion, NCNNO 2 −. The compound NCNNO 2 − appears to have formed by loss of HN 3 from (II) or N 3 − from (III) during one of the synthesis attempts of Rb(II). The major atom motions in the IR spectra of (I), (II), and (III) were assigned on the basis of density functional theory (DFT) using the B3LYP method. Both the IR spectral and crystal structure trends show that increasing the negative charge on the anion primarily shifts the partial double bond character from the CNNO 2 bond to the CNNO 2 bond.

STUDIES ON METAL-CONTAINING POLYURETHANES BASED ON DIVALENT METAL SALTS OF MONO(HYDROXYETHOXYETHYL)PHTHALATE

By reacting phthalic anhydride with excess of diethylene glycol and metal acetate, the metal salts of mono(hydroxyethoxyethyl)phthalate were prepared (metal = Cu2+, Mn2+ and Zn2+). Polyurethanes containing metal ions in the main chain were synthesized by reacting hexamethylene diisocyanate (HMDI) or tolulylene 2,4-diisocyanate (TDI) with Cu2+, Mn2+ and Zn2+ salts of mono(hydroxyethoxyethyl)phthalate using di-n-butyltin dilaurate (DBTDL) as catalyst. The prepared monomers and polyurethanes were characterized by FT-IR, 1H-NMR, 13C-NMR, UV spectra, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), elemental analysis, solubility and viscosity studies. The antibacterial activity of these polyurethanes have also been investigated using agar diffusion method.

Studies on polyurethanes and polyurethane-ureas derived from divalent metal salts of mono(hydroxybutyl) hexolate

Divalent metal salts of mono(hydroxybutyl)hexolate [M(HBH) 2 ), M=Ca 2+ , Mn 2+ or Pb 2+ ] were synthesized by the reaction of 1,4-butanediol, 5,6,7,8,10,10-hexachloro-3a,4,4a,5,8,8a,9,9a-octahydro-5,8-methanonaphtho-[2,3-C]-furan-1,3-dione and divalent metal acetates. Hexamethylene bis [N'-(1-hydroxy-2-methyl-prop-2-yl)urea] (HBHMPU) and tolylene 2,4-bis[N'-(1-hydroxy-2-methyl-prop-2-yl)urea] (TBHMPU) were synthesized by reacting 2-amino-2-methyl-propan-1-ol with hexamethylene diisocyanate (HMDI) and tolylene 2,4-diisocyanate (TDI), respectively, in toluene solvent. Flame-retardant metal-containing polyurethanes were synthesized by the solution polymerization of HMDI with M(HBH) 2 and the polyurethane-ureas by reacting HMDI with 1:1 mixture of M(HBH) 2 and HBHMPU or TBHMPU, respectively, in DMSO as solvent. The polymers have been characterized by elemental analysis, solubility, viscosity and IR and 1 H NMR spectroscopy. The thermal stability of the polymers has been studied by thermogravimetry. The flame-retardant property of the polymers has been investigated by measuring limiting oxygen index values.

Synthesis and characterization of metal-containing polyurethanes and polyurethane-ureas

Metal-containing polyurethanes containing ionic linkages in the main chain were synthesized by the polyaddition reaction of hexamethylene diisocyanate (HMDI) or toluylene 2,4-diisocyanate (TDI) with 1:1 mixtures of divalent metal salts of mono(hydroxybutyl)phthalate [M(HBP) 2] and digol [DG]. Similarly polyurethane-ureas were synthesized by reacting the diisocyanates with 1:1 mixtures of hexamethylene bis( ω, N-hydroxyethyl-urea) (HBHEU) and M(HBP) 2. The polymers were characterized by elemental analysis, thermogravimetric analysis, solubility, visocity and spectral studies.

Synthesis and Characterization of Metal Containing Polyurethanes and Polyurethane-Ureas Based on New Divalent Metal Salts of Mono(Hydroxybutyl)Phthalate

ABSTRACT Divalent metal salts of mono(hydroxybutyl)phthalate were synthesized by the addition of 1,4-butane diol, phthalic anhydride and divalent metal [Ca2+, Mn2+ and Pb2+] acetates. A series of metal containing polyurethane and polyurethane-ureas containing ionic links in the main chain were synthesized by the polyaddition reaction of hexamethylene diisocyanate (HMDI) or toluylene 2,4-diisocyanate (TDI) with divalent metal salts of mono(hydroxybutyl)-phthalate [M(HBP)2] and 1:1 mixtures of toluylene 2,4-bis(ω, N-hydroxyethylurea) [TBHEU] and M(HBP)2. M(HBP)2 and the polymers were characterized by elemental analysis, solubility, viscosity, spectral studies (IR and FT NMR) and thermogravimetric analysis (TGA).

ChemInform Abstract: Acidity of Dibasic Carbon Acids. Part 3. Ion Solvation State of Monometallic Salts of 9,10‐Dihydroanthracene and Its Derivatives in THF

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Acidity of dibasic carbon acids. Part 3. Ion salvation state of monometallic salts of 9,10-dihydroanthracene and its derivatives in THF

The ion solvation state of monometallic salts of 9,10-dihydroanthracene (DHA) and its 9,10-disubstituted derivatives in THF has studied by UV–VIS and 1H and 13C NMR spectroscopy. At room temperature, lithium 9-phenyl-9,10-dihydroanthracen-9-ide, lithium 9,10-dimethyl-9, 10dihydroanthracenide and lithium 9,10-diphenyl-9,10-dihydroanthracemde exist as solvent separated ion pairs (SSIP). Lithium 9,10-dihydroanthracene, lithium 9-methyl-9,10-dihydroanthracen-10-ide and sodium, potassium and rubidium 9-phenyl-9,10-dihydroanthracen-9-ides, 9,10-dimethyl-9, 10dihydroanthracenides and 9,10-diphenyl-9,10-dihydroanthracenides exist as a mixture of SSIP and contact ion pairs (CIP). Sodium, potassium, rubidium and caesium 9,10-dihydroanthracenides, 9-methyl-9,10-dihydroanthracen-10-ides and 9-cyano-9,10-dihydroanthracenides exist as CIP in solution. The stabilizing effect of the methyl and phenyl substituents is more significant for SSIP than for CIP. The thermodynamics for SSIP to CIP conversion is determined for the sodium salts of DHA and its derivatives. ΔS° is 27 ± 2 cal mol–1 K–1ΔH° increases with substituent size and charge dispersion. A model for the transition of CIP of alkali-metal salts of DHA and its derivatives into SSIP is suggested. The model takes into account the geometry and charge distribution in anions.

Acidity of dibasic acids I: the second acidity constant of 9,10-dihydroanthracene and its 9,10-substituted derivatives: effect of substituent and counter ion

The second equilibrium ion pair acidity constants (pK2) of 9,10-dihydroanthracene, 9-phenyl-9,10-dihydroanthracene, 9,10-diphenyl-9,10-dihydroanthracene and 9-cyano-9,10-dihydroanthracene with sodium, potassium and rubidium have been determined in tetrahydrofuran (THF) at 25 °C in the concentration range l0–5–10–2 mol dm–3. Equilibria were monitored by UV–VIS and 1H NMR spectroscopies and the spectra of the dimetallic and monometallic salts reported. The dimetallic salts of all the dibasic carbon acids studied behave as contact ion pairs in THF. The pK2 of 9,10-dihydroanthracene is insensitive to substituent effect but is strongly dependent on the cation.

Polymers based on divalent metal salts of mono(hydroxyethyl) phthalate—a review

AbstractDivalent metal salts of mono(hydroxyethyl) phthalate are useful starting materials for synthesis of ionic polymers into which metal is firmly incorporated. This article surveys a series of polymers that have been synthesized by using metal salts. The salts can react with compounds having functional groups capable of reacting with hydroxyl groups. By polyaddition reactions of the salt‐diol with diisocyanates in dimethylformamide, metal‐containing polyurethanes, polyurethane‐ureas, and isocyanurate‐type crosslinked polyurethanes are obtained. In polycondensation reactions of the salt‐diols with anhydrides, some systems give unsaturated polyesters soluble in styrene. Meanwhile, polyaddition reactions of systems of the salt‐anhydride‐epoxide give metal‐containing polyesters containing ionic links in the main chain. The metal carboxylate groups of the salts catalyze the reactions in this case. The reactions have offered a commercially favorable synthetic route. Through the proper selection of components, various types of metal‐containing unsaturated polyesters, cured resins, and cured rubbers are obtained. The effect of introducing metal on their physical and other properties results, and, in addition, generally Mg is more effective than Ca in improving the properties of the polymers.

Stability, cure properties, and applicability as one part adhesives of systems of divalent metal salts of mono(hydroxyethyl) phthalate–anhydride–bisepoxide

Heterogeneous curable compositions of divalent metal salts of mono(hydroxyethyl) phthalate–anhydride–bisphenol A diglycidyl ether (BADG) systems were prepared by merely mixing these components at room temperature. Stability at room temperature and cure properties at high temperature of the compositions were investigated for evaluating their applicability as one part adhesive. It was found that the systems containing Mg were generally more stable than those containing Ca. Similarly, at 150°C the Ca-containing systems showed generally shorter gelation time than the Mg-containing ones, due to the fact that the Ca salt dissolves more rapidly and enters into the addition reaction with the anhydride, leading to the faster appearance of the catalytic activities of the Ca carboxylate group. Among the various combinations of components, the metal salt–succinic anhydride (SA)–BADG systems were stable at room temperature for more than 6 months and rapidly cured at high temperature, showing excellent adhesive properties. This result indicates that the SA-containing systems should be of interest in applications to one part adhesives.

Crosslinking of poly(ethylene glycol) with divalent metal salts of mono(hydroxyethyl) phthalate, anhydride, and bisepoxide

AbstractPoly(ethylene glycol)s (PEG) were crosslinked with divalent metal salts of mono(hydroxyethyl) phthalate, anhydride, and bisepoxide to give metal‐containing cured rubbers. As the anhydride, hexahydrophthalic anhydride was used, and bisphenol A diglycidyl ether was the bisepoxide used. As for the physical properties of the cured rubbers obtained, the rubbers containing Mg showed much better physical properties than those containing Ca. In addition, the rubbers with high hard block contents and high overall crosslinking densities exhibited high tensile strength and Shore A hardness, and so did the rubbers having a high degree of crystallinity of the PEG soft block. The occurrence of crystallization became easy as the soft block length became longer and the soft block content became higher, or as the crosslinking density of the hard block became lower. The PEG‐based rubbers showed much higher water absorption than the previously reported poly(propylene glycol)‐based rubbers, due to the much higher hydrophilicity of the PEG block. Resistance to chemical attack and stress–relaxation are also discussed.

Crosslinking of polypropylene glycol with divalent metal salts of mono(hydroxyethyl) phthalate, anhydride, and bisepoxide

AbstractCrosslinking of polypropylene glycol with divalent metal salts of mono(hydroxyethyl) phthalate, anhydride, and bisepoxide is investigated. The anhydride and bisepoxide were hexahydrophthalic anhydride and bisphenol A diglycidyl ether. The metal carboxylate groups catalyzed the crosslinking reactions. The Mg carboxylate group showed higher catalytic activities than the Ca carboxylate group. The rubbers containing Mg showed much better physical properties than those containing Ca, due to higher interionic attraction of Mg++ and better homogeneity. In addition, tensile strength of the cured rubbers at about the same soft block contents depended largely upon that of the hard block. Resistances to water and chemical attack, stress–relaxation, and thermal behavior are also discussed.

Crosslinking of hydroxyl‐terminated liquid rubber with divalent metal salts of mono(hydroxyethyl) phthalate, anhydrides, and bisepoxide

AbstractCrosslinking of hydroxyl‐terminated liquid rubber with divalent metal salts of mono(hydroxyethyl) phthalate, anhydrides and bisepoxide was investigated by the diols‐anhydridesbisepoxide, reactions. As the anhydride, succinic anhydride and hexahydrophthalic anhydride were used, and bisphenol A diglycidyl ether was the bisepoxide used. The metal carboxylate groups of these metal salts catalyzed the crosslinking reactions and, further, the Mg salt showed higher catalytic activities than the Ca salt. As for the physical properties of the metal‐containing cured rubbers obtained, tensile strength and Shore A hardness increased with increase in the metal salt content. In addition, the rubbers containing Mg showed better physical properties than those containing Ca. Meanwhile, elongation showed a maximum with increase in the metal salt content. Resistance; to water and chemical attack, thermal behavior, and stress relaxation are also discussed.

The kinetics and mechanisms of thermal degradation of some divalent metal salts of mono(hydroxyethyl) phthalate

The thermal decomposition of lead and manganese salts of mono(hydroxyethyl) phthalate was studied by thermogravimetry and differential scanning calorimetry. The kinetic parameters for the various stages of decomposition of these salts were calculated by different methods and mechanisms are proposed to explain the results.