Silver compounds solvent extraction

Organ oselenium compounds, such as phosphine selenides, are being evaluated in solvent extraction systems for silver and gold (63). Also, potential pharmaceuticals containing selenium have been prepared (64). 

Cage hydrocarbons with a sperical cavity, such as 104 or 105, are fullerene models [63]. They were prepared by intramolecular sulfide cyclization of suitable hexabromo precursors, oxidation and sulfone pyrolysis [64]. The overall yields were 5% resp. 3.5%. Compound 104, with the constitution C60H60, might be envisaged as a fullerene precursor. In addition, the compound shows a high affinity to silver(I) ions in solvent extraction experiments. 

If the ratio be unity, the concentrations of the solute in each solvent will be the same if the ratio be far removed from unity, a correspondingly large proportion of the solute will be found in the one solvent which can be utilized to extract the Soln. from the other solvent. E.g. ether will remove ferric chloride from its aq. soln., and since many other chlorides are almost insoluble in ether, the process is utilized in analysis for the separation of iron from the other elements the solubility of cobalt thiocyanate in ether is utilized for the separation of cobalt perchromic acid is similarly separated from its aq. soln. by ether molten zinc extracts silver and gold from molten lead the extraction of organic compounds from aq. soln. by shaking out with ether or other solvent is much used in organic laboratories. 

The analysis of particle bound PAH involves collection of PAH bound to dust particles on 0.8 pm glass fiber or silver membrane filters, desorption of PAH from the particles into a suitable organic solvent, and analysis of the extract by a capillary GC using an FID. Between 500 and 1000 L air at a flow rate of 120 L/h is recommended for sampling, which can give a detection limit of 0.15 to 0.50 pg/m3 for each compound (Riepe and Liphard, 1987). The method suggests the installation of an absorber resin, such as XAD-2 or Tenax, after the... 

Most of the recent literature in this field is concerned with synthetic organic reactions, supramolecular chemistry and crystal engineering. However, solvent free approaches can also be used in the extraction of natural products, although less information is available in the mainstream literature. Juice extractors can be used to afford aqueous solutions of biologically active compounds from undried plant material. An extract of Capsicum annum L. was recently prepared in this way, and then used in the green synthesis of silver nanoparticles. The actual synthesis of the nanoparticles was conducted in the aqueous phase and therefore this work will not be discussed further here. However, this solvent free approach to extraction is probably worthy of greater representation in the green chemistry literature. 

In the cat s adrenal cortex, Bennett found that yellow phenylhydra-zones and metallic silver both appeared predominantly in the outer portion of the zona fasciculata, the so-called spongy zone. These reactions failed to develop if the sections were previously extracted with acetone or ethyl alcohol at room temperature, indicating that the reactive compounds were readily soluble in such lipid solvents. In this same zone, the cells contained abundant small hpid droplets, as demonstrated with Sudan dyes or osmic acid. 

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