According to 1970s studies suggest that its mechanism are basically two: one is a pair of xanthate xanthate oxidation product plays a major role; the other surface of the metal is gold minerals xanthates play a major role. The former is determined by a large number of electrochemical tests, the latter mainly by infrared spectroscopy. There are also secondary views, for example, some believe that it may be that the elemental elemental sulfur acts.
   1973, Identification of the reaction product of the surface and galena xanthate is then extracted to make spectral characterization. The results of direct infrared spectroscopy were published in 1973. It was confirmed that only the metal xanthate was formed on the surface of galena, but no double xanthate.
The results of the potentiodynamic measurements published in 1974 showed that when lead xanthate was formed, lead excess or xanthate was excessive, and the measured potentials were different, the former being -20 mV and the latter being -50 mV , while the double xanthate was The potential is related to the pH value. When pH=7 , the potential is -70 mV , and when pH = 11 , the potential is -140 mV . The surface of the galena treated with xanthate has a dynamic potential close to lead xanthate, which is quite different from the double xanthate. At the time of actual measurement, the concentration of xanthate was higher than that of normal flotation. Therefore, it is considered that under normal flotation conditions, no xanthate is formed on the surface of galena.
A large number of electrochemical measurements showed that when the surface potential of galena was -0.2 V and 2.0 V , chemisorption occurred, and when the surface potential continued to increase above 2.0 V , a double xanthate was gradually formed. It is also known from experiments that the nitrogen bubbles do not adhere to the galena electrode of less than 2.0 V. When the surface potential is greater than 2.0 V , the nitrogen bubbles adhere, which proves that the presence of the double xanthate is favorable for the adhesion of the ore particles to the bubbles. The chemical adsorption reaction proposed by the electrochemical measurement results is:
PbS   +  2X -  → PbX 2 + S + 2e
Galena      Yellow drug ion Lead xanthate
    The long-term electrolysis of the xanthate solution was carried out using galena as an electrode, and it was found that lead xanthate and xanthate were simultaneously formed, and the ratio of the two was between 3 and 0.5 , which was different with different galena electrodes. The sulfur ions in the crystal lattice are not formed into elemental sulfur under electrolysis conditions, but are oxidized to thiosulfate. The reaction is to form a layer of chemisorbed xanthate, then deposit several layers of double xanthate, and finally form lead xanthate and dihuang.
In the 1930s , people tried to use the double xanthate as a collector . The results showed that the double xanthate had a trapping effect on the lead. However, on the surface of the galena, it is the direct physical adsorption of the double xanthate, or the chemical adsorption of the double xanthate to the galena surface, or even the chemical reaction to form lead xanthate, which has not been determined for a long time. In 1975 , studies on the surface effects of xanthate and xanthate on the surface of lead ore by radioisotope tracer showed that the chemical adsorption was lead xanthate, while the xanthate was only physical adsorption. Moreover, physical adsorption mainly occurs in the "anode region" of the galena surface. This physically adsorbed xanthate may diffuse into the "cathode zone." In the cathode region, the xanthate is reduced to form xanthate, and the possible surface reactions are:
 PbS      +     X 2 - - PbX 2 + S
Galena surface     Double yellow drug      Lead xanthate
   If this is a bulk reaction,
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