【作者】 陈海燕；

【导师】 张胜涛；

【作者基本信息】 重庆大学 ， 化学， 2011， 硕士

【摘要】 为解决同槽电解锰和电解二氧化锰存在的电流效率低,能耗高等问题,本文进行了同槽电解锰和二氧化锰的研究。采用恒电流、循环伏安、线性扫描、恒电位等电化学方法,通过对比实验,为同槽电解中选择合适的电解质、电极材料以及电解槽提供了实验依据。论文采用了X-射线衍射法来鉴别和确定目标产物的结构和组成以及用SEM来观察阴极产物的表面形貌。采用正交实验研究了阴阳极电流密度、阴阳极室的pH、阴阳极室的锰离子浓度以及氯化铵浓度对同槽电解的影响。通过对比实验研究了在硫酸盐介质和氯盐介质中阳极电流效率和槽电压的差异,为选择合适的电解介质提供了实验依据。结果表明在小于65℃氯盐溶液比硫酸盐溶液具有高的电流效率。在相同温度下,氯盐溶液比硫酸盐溶液的初始槽压低,10h内达到10V槽压所用的时间长。在相同的实验条件下氯盐溶液比硫酸盐溶液达到稳定槽压的温度低。因此选择氯盐溶液作为同槽电解的电解液。在氯盐溶液中分别以钛钌板和钛板为阳极,通过对比实验发现,电解二氧化锰的电流效率差别不大,而钛钌板为阳极具有低且稳定的槽压,所以在氯盐溶液中选择钛钌板为阳极板。论文通过实验比较了在不锈钢和钛板上沉积锰的情况,发现在不锈钢上沉积的锰纯度高,而在钛板上沉积的锰含有杂质,所以选择不锈钢作同槽电解的阴极。为选择合适的电解槽本文采用循环伏安法和恒电流法研究了隔膜对电解锰和二氧化锰的影响。结果表明隔膜对沉积锰非常有利,在同槽电解中选用隔膜电解槽。在确定电解介质、电解槽、电极材料之后,在两极同温同槽条件下,采用恒电流法研究了时间对同槽电解锰和二氧化锰的影响。结果发现阴阳极室的pH、电流效率均随时间发生变化,而pH与电流效率的变化趋势无对应关系,由于实验采用的是固定溶液浓度的方法,时间的变化反映离子浓度的变化,说明η不只与pH有很大关系,而且与其他离子浓度有非常密切的联系。本文通过正交实验研究锰离子的浓度、pH、电流密度和氯化铵浓度对同槽电解锰和二氧化锰的槽压、电流效率以及能耗的影响。通过对实验结果分析,选择优化的实验条件电解,即C_Mn²⁺),A取1.0mol/L,pH_A取1,JA取50 A/m^-2,C_Mn²⁺,C取0.9 mol/L,CNH₄⁺取1.8 mol/L,pH_C取7,JC取250 A/m^-2,在该实验条件下恒电流电解2小时,得到的实验结果为:U=3.60v,η_A=90.07%,W_A=2464 kW_h/t, WC=3794 kWh/t,η_C =92.56%。更多还原

【Abstract】 In order to solve the low current efficiency and high energy-consumption the simultaneous electrolysis of manganese metal and dioxide in the same cell, the simultaneous electrolysis of manganese metal and dioxide in the same cell was studied in this paper. Through contrast experiments,using electricity chemistry methods, such as constant potential,current density, cyclic voltammetry and line scanning, which provided experiment basis for the simultaneous electrolysis of manganese metal and dioxide in the same cell chosen the electrolyte , electrode material and electrolysis cell. The surface morphology and the crystal structure of manganese and manganese dioxide electrodeposits are analyzed by scanning electron microscope （SEM） and powder X-ray diffraction spectrometer （XRD）, respectively. Cathode anode room current density, pH, concentration of manganese ion and concentration of ammonium chlorination to the influence of simultaneous electrolysis was studied in this paper by orthogonal experiments.The anode current efficiency and the cell electric voltage in chlorine and sulfate electrolysis was studied respectively in this paper, which provided an experiment basis for simultaneous electrolysis chosen the suitable electrolysis. Through contrast experiments, it was found that the current efficiency in chlorine electrolysis is higher than that in sulfate electrolysis below 65℃; Under the same temperature, the beginning cell electric voltage in chlorine electrolysis is lower than that in sulfate electrolysis, the cell electric voltage grow to 10 V consuming more time; under the same experiment condition ,the temperature of reaching the stable cell electric voltage in chlorine electrolysis is lower than that in sulfate electrolysis. Consequently chosen chlorine electrolysis as the same cell electrolysis.Through contrast experiments, it was found that the current efficiency of the electrolysis manganese dioxide is almost the same titanium ruthenium plank and titanium plank as anode in chlorine electrolysis. But titanium ruthenium as anode have low and stable cell electric voltage. So chosen titanium ruthenium as anode in chlorine electrolysis. Through contrast experiments, it was found that deposition manganese is high pure degree on the stainless, but the deposition on the titanium is imply impurities, so chosen the stainless steel as cathode in the same cell electrolysis.For choosing suitable electrolysis cell, membrane’s effect for the electrolysis manganese and the manganese dioxide by cyclic voltammetry and constant current density was studied in this paper. The result discovered membrane is beneficial for deposition manganese. So chosen membrane cell in simultaneous electrolysis.After choosing electrolyte, electrode materials, electrolysis cell, the influence of the time to the same cell electrolysis manganese and manganese dioxide under the same anodic and cathodic temperatures was studied in this paper. The results indicated cathode anode room pH changed with time variety, but the pH variety trend was not corresponding with current efficiency . Because the experiment adopt electrolysis immovability, time of variety response ion density of variety. The experiments’ results showed that theηis not only closely related to pH, but very closely contact with other ion densities.Current density, pH, concentration of manganese ion and concentration of ammonium chlorination to the influence of cell potential, current efficiency and energy consume of simultaneous electrolysis manganese and dioxide manganese was studied in this paper. Through a analytical of the experiment result, chosen an excellent experiment condition for electrolysis, namely C_Mn²⁺,A took 1.0mol/L,pH_A took 1,JA took 50 A/m^-2,C_Mn²⁺,C took 0.9 mol/L,CNH₄⁺ took 1.8 mol/L,pH_C took 7,J_C took 250 A/m^-2. Constant current electrolysis for 2 hour under the experiment condition, the experiment result: U=3.60v,η_A=90.07%,W_A=2464kWh/t,W_C=3794kWh/t,η_C =92.56%.更多还原