Electrochemical Mechanism Study Of Collector Adsorptions On Natural Gold Surface

The mechanisms of reaction between collectors and natural gold was not so clear. The adsorption type and strength of xanthate, thiourea derivatives and xanthogenate on gold electrode, and their evolution when solution concentration, temperature and pH changes was studied in this thesis by the means of testing cyclic voltammograms curve and tafel curve. Then, by using the contact angle of determination to verify the influence of their adsorption on gold the electrode surface to hydrophobicity. So as to provided theoretical guidance for developing new gold collector. The results were as follows:Dixanthates were created after the xanthates were oxidated on the gold electrode surface; Along with the increase of concentration, temperature, the adsorption manner of xanthates on the gold electrodes surface were unchanged, and the density of dixanthates hydrophobic membranes was increased, the contact Angle was also increased; Along with the increase of pH, the oxidizing reactions of xanthates were abated, contact Angles were smaller; Along with the extension of hydrocarbon chains, the potential of oxidation reaction of xanthates reduced, corrosion current decreased, catch ability of gold enhanced.The adsorption of allyl thiourea on gold electrode surface was chemical adsorption, while the adsorption of S-benzyl thiourea hydrochloride on gold electrode surface was physical adsorption; With concentration, temperature, pH increased, their adsorptions were enhanced, the passivation degree and the contact Angle is increased. As for the ability of increasing the gold electrode hydrophobic, S-benzyl thiourea hydrochloride was more effective than allyl thiourea.Physical adsorption of Xanthate formic acid ethyl ester on gold the electrode surface was happened. And with the increase of concentration and temperature, adsorption enhanced, the passivation of gold electrodes surface enhanced, and the contact Angle was bigger. And with the increase of temperature, slight chemical adsorption of isopropyl xanthate formic acid ethyl ester on gold electrode was happened. Along with the increase of the pH, the absorptions of xanthate formic acid ethyl ester on gold electrode were abated, contact Angles were reduced. And in acid conditions, these changes were more obvious. Along with of hydrocarbon chains extending, the potential of the oxidation reaction between xanthate formic acid ethyl ester and gold reduced, corrosion current decreased, catch ability to gold enhanced.The adsorption of Xanthate propylene esters on gold electrode surface were physical adsorption. The absorption membrane could be reduced, while gold electrode potential was lower, and along with the growth of the hydrocarbon chains, reduction abated. With concentration and temperature increase, adsorption of enhanced, and the contact Angle was bigger. Along with the increase of the pH, the absorption of xanthate acrylic ester on gold electrodes abated, contact Angle decreased. Along with of hydrocarbon chains extending, the potential and corrosion current of the oxidation reaction between Xanthate propylene esters and gold increased, catch ability to gold enhanced.