Synthesis of meso-tetra-(2-chloro-4-sulfophenyl) prophyrin and spectrophotometric determination of trace amounts of cadmium
Synthesis of a new high sensitive water soluble chromogenic reagent meso-tetra-(2-chloro-4-sulfophenyl) prophyrin and the conditions for the reaction of this reagent with cadmium (I) were studied. The apparent molar absorption coefficient at 434 nm is 5.20×105 L·mol−1·cm−1. The method has been applied to the determination of 5.0×10−9 (content by weight) Cadmium (I) in honey.
SEPARATION OF CADMIUM FROM URANIUM, COBALT, NICKEL, MANGANESE, ZINC, COPPER, TITANIUM, AND OTHER ELEMENTS BY CATION EXCHANGE CHROMATOGRAPHY
A study of the distribution curves of cations with AG 5OW-X8 resin in hydrochloric acid showed that most cations are adsorbed strongly from 0.5 N hydrochloric acid, while cadmium is not. This fact was used to develop a cation exchange chromatographic procedure to separate cadmium from uranium, cobalt, nickel, manganese, zinc, copper, and titanium. Other cations that are completely separated include Mg/sup 2+/, Ca/sup 2+/, Sr/sup 2+/, Ba/sup 2+/, Fe/sup 2+/, Fe / sup 3+/, Al/sup 3+/ ZrO/sup 2+/, Th/sup 4+/, Y/sup 3+/, La/sup 3+/ and the rare earths, and Cs/sup + Stannic tin accompanies cadium quantitatively and can be separated from the cations named above by a similar procedure. (auth) The solids obtained by heating a mixture of UO/sub 2/, ZrO/sub 2/, and ThO/sub 2/ to 1400 deg C in a current of H/sub 2/ were studied. In the ZrO/sub 2/-poor region a cubic phase is formed in these conditions in which the ZrO/sub 2/ concentration goes gradually from a maximum of 17 mole% to less than 1 mole% with an increase in the amount of Th present. The ZrO/sub 2/ can dissolve about 8 mole% of UO/sub 2/. The solubility limit found for 1000 deg C practically coincidedmore » with that of the solids obtained at the slightly higher temperature. (tr-auth)« less
Spectrophotometric determination of copper with α, β, γ, δ-tetraphenylporphine trisulfonate
Water-soluble porphyrin, α, β, γ, δ-tetraphenylphorphine trisulfonate (TPPS, H2R), was found to be a very useful agent for both the direct spectrophotometric determination and the photometric titration of copper(II). The molar absorptivity of H4R2+ at 434 nm is 5.0·105 and the spectrophotometric sensitivity is 0.00013 μg Cu cm−2 for A=0.001. Beer's law is followed in the range 0.006 μg–0.06 μg Cu ml−1. Among twenty-two elements examined, only zinc(II) seriously interfered. Acid dissociation constants and salt effects on the spectra of TPPS were evaluated.