Four Sulfonic Acid Cobalt Phthalocyanine Reaction With Sulfur Compounds

A new method which uses multi-wavenumber and double-parameter to analysize the UV-VIS spectra is proposed to determine the composition and stablization constants of coordination compounds.With this method, the disaggregation of cobalt tetrasulphated phthalcyanine [CoTSPc] in water and solution with addition of n-hexadecyltrimethyl-ammoniumbromide [CTAB] was investigated. The effects of CoTSPc on the first cmc have studied by the method of the conductivity. The electron-rich N in the CoTSPc can supply electron to the CTAB cation, which leads to the location of CoTSPc in the outside of micellar palisade.The reaction of CoTSPc and sodium sulfide[Na2S] is studied. The result shows that pH of the medium has great effect on the reaction. A five coordinated compound Co(II)TsPc(HS) is formed at pH=7.0 . The equilibrium constants and thermodynamics are reported for the reaction. At higher pH, a redox-reaction takes place and a five coordinated compound with the oxidation number I for Cobalt [SCo(I)TsPc] is found.By the same means, the influence of CTAB on the reaction between cobalt tetrasulphonated phthalocyanine and sodium sulfide has been investigated. The result shows that in the presence of the micelles , cobalt tetrasulphonated phthalocyanine can be reduced by sodium sulfide at pH 8.5-9.5 to give corresponding Co(I) complex.. The mechanism of the reaction is discussed. Using the method of multi-wavelength and double-parameters , UV-VIS spectra of the system areanalysized and the thermodynamics data are calculated.The reaction between CoTSPc and mercaptoethanol [RSH] has been studied. The result shows that no reaction happens at low pH and low mercaptoethanol concentration. Meanwhile, in the presence of CTAB micelles , CoTSPc can be reduced by mercaptoethanol to give corresponding Co(I) complex. HPLC is used to ananlyse theproduct, which testified the result. The rate of the reaction between RSH and oxygen, which is catalysed by CoTSPc ,is determined by the decrease of oxygen volume. When the concentration of RSH is less than 4.26 x 10^-3 mol · L^-1, the rate equation is:r = 3. 8 x 10^-6 [CoTSPc][RSH][O₂]The possible reaction mechanism was proposed.