Metal-phthalate complexes

The Dionex column caused each of the metal ions to be completely retained. The authors reasoned that this behavior was due to the presence of unreacted surface-sulfonated PS-DVB macroparticles which were capable of adsorbing the metal cations. A mixed retention mechanism was theorized for the other three columns. In addition to anion-exchange of negatively charged metal-phthalate complexes, the authors suggest that adsorption of neutral metal-phthalate complexes might contribute to the retention of each metal ion. This theory was based on the fact that since the stationary phase of the Hamilton, Waters, and Vydac columns were comprised of different materials, these materials would have different hydrophobicity which would lead to differences in adsorption of the neutral metal-phthalate complexes on each column. This was corroborated experimentally, as the metal ions were retained more strongly on the more hydrophobic column (PS-DVB from Hamilton). The dominant mechanism of retention was similar for each column because there were no differences in metal ion elution orders between the three columns. 

Complexing agent for metal salts. Complexes with KMn04 to form a benzene-soluble oxidant and with other polar reagents to increase solubility in nonpolar solvs. Used in extraction-separation of Hg, Ag as 1% soln. in dipentyl phthalate as ionophore in K-selective electrode. Colourless or pale yellow wax. Mp 38-54°. Bp 344°. 

The CL reaction of luminol (5-amino-2,3-dihydro-1,4-phthalazinedione) (1) is one of the more commonly used nonenzymatic CL reactions and has been extensively studied [49, 57-59], It is well known that the luminol CL reaction is catalyzed by many kinds of substances, e.g., ozone, halogen-Fe complex, hemin, hemoglobin, persulfate, and oxidized transition metals. The most acceptable scheme is shown in Figure 10. Luminol forms a six-membered ring of peroxide (3) from a diazaquinone intermediate (2) and then, by the decomposition of 3, N2 gas and the Si-excited state of the phthalate dianion are produced, yielding... 

Azomethine metal complex pigments replace the metal with tin stabilizers, resulting in a change in shade. In the case of manganese-laked pigments trouble can also be expected in the presence of epoxy compounds. Pigment preparations based on epoxidized soya bean oil are normally used instead of diisodecyl phthalate pastes in the automotive sector e.g. for coloring PVC roofs etc. 

In SL-PC, a catalyst is supported on a solid matrix in the form of the film of a nonvolatile liquid phase adsorbed on the solid. The catalytic film can be, for example, a molten salt or a molten oxide (e.g., Deacon s catalyst (CUCI2/KCI) used to oxidize HCl with oxygen for the chlorination of ethylene in the synthesis of vinyl chloride. Figure 6.1 V2O5 for the oxidation of sulphurous to sulphuric anhydride). Alternately, it can be a liquid phase (e.g., ethylene glycol, PPh3, butyl benzyl phthalate, etc.) that contains a soluble catalytic species such as a metal complex. 

M). Large rate enhancements occur for base hydrolysis of the complexes, ranging from 104 with Ni° to 106 with Cu11. A pH-independent reaction occurs with the phthalate monoester due to intramolecular nucleophilic attack by the neighbouring carboxylate group leading to rate enhancements of 102-104. Metal ion-promoted water hydrolysis was also observed with these esters. 

Waste constituents may be immobilized in a soil system mainly by sorption and/or partitioning. Adsorption on soil particles is competitive, pH-dependent and, usually, inversely proportional to the solubility of the compound in water. Dry soils are better adsorbents than wet ones. HSs are able to form complexes with metal ions and hydrous oxides and also interact with minerals and a variety of organic compounds, including alkanes, fatty acids, dialkyl phthalates, pesticides and herbicides, and may therefore increase the concentration of these constituents in soil and natural waters. 

Adsorption of a high-boiling solvent onto a high-surface-area microporous solid yields a supported liquid phase that can be removed from the sohd only by extraction with a second solvent or by distillation at high temperature under vacuum. Under typical reaction conditions, a solid that contains a supported liquid phase looks and behaves as a solid, yet it can dissolve small quantities of a metal complex into the supported phase. One of the first examples of this arrangement was achieved with the immobilization of Rh(CO)(PPh3)2Cl in benzyl butyl phthalate on silica. The supported complex was successfiilly used to effect the gas-phase hydroformylation of propene. 

Pulp and paper mill sludge is a complex and changeable mixture of dozens or even hundreds of compounds. Some are well known, like natural wood extractives, organochlorines, organosulfides, and dioxins. Priority pollutants and chemicals of concern that must be analyzed in pulp mill residues include heavy metals, chlorinated hydrocarbons, chlorobenzenes, PAHs, chlorinated phenols, chlorinated catechols, chlorinated guaiacols, phthalates, resin acids, alkylphenols and alkylphenol ethoxylates, and plant sterols. 

Storage of water samples to detect trace metals is normally carried out in plastic containers fluorinated plastic materials i.e.. Teflon, fluorinated ethylene propylene (FEP), perfluoroalkoxy polymers (PFA) or polyethylene are used because if opportunely treated and conditioned they guarantee contamination-free samples. However, FEP or Teflon bottles are preferable to those made of polyethylene when speciation studies are carried out. In fact, polyethylene over long periods of storage can release plasticizers (above all phthalates or amines), which behave as ligands and modify the complexation equilibria of the solution. When Hg is to be determined plastic materials must be avoided because they are permeable to gases and vapours glass or quartz are therefore used. 

The pH of coloured solutions is often stabilized by means of suitable buffers. Tartrate, citrate, phosphate and phthalate solutions are usually avoided since they can bind many metals in stable complexes. Acetate solutions are often used, although they also can form complexes with some metals ie.g., Al, Be). Acetate buffers may be replaced by hexamethylenetetramine buffers. 

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