Study On The Adsorption Performance And Technology Of Antimony-based Adsorbent For Bismuth Ions In Copper Electrolyte

With the progress of the copper electrolytic refining production process,impurities such as bismuth,arsenic and will antimony gradually accumulate in the electrolyte and eventually cause damage to the product quality.Aiming at the problem of impurity bismuth removal in copper electrolyte,this paper prepares a new antimony-based sorbent to achieve high-efficiency removal of impurity bismuth in copper electrolyte.The main contents are as follows:Firstly,Sb₂O₃ was used as the precursor and H₂O₂ was used as the oxidant to synthesize the antimony-based adsorbent.The preparation conditions of the antimony-based adsorbent were studied,and the single factor experiment of copper electrolyte adsorption and removal was carried out.The results show that the temperature is the key factor affecting the preparation effect.The optimum conditions for the removal of sorbent in the electrolyte are:Sb input 3 g·L^-1,temperature 90°C,time 60 min,rotation speed 200 r·min^-1.Finally,the bismuth removal rate is up to 90%and the sorbent is substantially free of dissolution losses.Secondly,combined with adsorption kinetics model,adsorption isotherm model and XRD,SEM,IR,potentiometric titration and other characterization methods,the adsorption properties of antimony-based sorbents were studied.The results show that the main phase of the adsorbent is Sb₂O₅·3H₂O,which is negatively charged and more electronegative in the acidic system.After adsorption and removal of the adsorbent,a large amount of flocculent amorphous Sb-Bi bond is formed on the surface.The adsorption of Bi ions by the adsorbent conforms to the Langmuir isotherm model and the adsorption process is a spontaneous,endothermic,entropy-increasing,physical and chemical adsorption process.The main interactions are hydrogen bonding and dipole.The interaction between the adsorbents and the Bi ions conforms to the pseudo-second-order kinetic model and the adsorption process can be divided into three stages:external surface adsorption,internal surface adsorption and equilibrium adsorption.Again,the relationship between the total concentration of Bi ions in solution and the total concentration of chloride ions,the relationship between the concentration of each dissolved component and pH under[Cl]=0.5,2,4 mol·L^-1 and the corresponding Bi are plotted.The concentration group is assigned a sub-graph.The results show that increasing the chloride ion concentration and pH value is beneficial to increase the concentration of Bi in the solution.Under the condition of chloride ion in the solution,Bi mainly forms BiCl²⁺,BiCl₂⁺,BiCl₃ and BiCl₄^-with chloride ions.when the pH is low,Bi in the solution mainly exists in the form of BiCl₂⁺,while when the pH is higher,Bi in the solution is mainly The form of BiCl₄^-exists.Finally,the single factor test of desorption of antimony-based sorbent and the adsorption-desorption cycle experiment were carried out.The results show that the desorption rate of Bi can reach 80 under the conditions of pH 0.5,sodium chloride concentration of 2 mol·L^-1,desorption temperature of 90°C,desorption time of 30 min and solid-liquid ratio of 1:5.The cycle properties and stability of the adsorbent are good.The adsorbent is added to the adsorbent according to the amount of Sb=3 g·L^-1,and the deuterium-chlorine salt desorption cycle experiment is carried out.After 5 cycles,the removal rate remains at 80%.about.