电解法制备甲基磺酸亚锡及其性能研究

发布时间：2018-01-28 21:49

本文关键词： 甲基磺酸亚锡电解均匀设计稳定性阳极溶解　出处：《沈阳理工大学》2010年硕士论文　论文类型：学位论文

【摘要】：随着工业的迅速发展,人们越来越关注电镀液的安全性、稳定性及环保性。甲基磺酸亚锡镀液体系不但稳定、低毒性、低腐蚀、镀层质量高、可在高电流密度下操作,而且可生物降解为硫酸盐和二氧化碳,更具环保性,故其工业化发展潜力十分明显。然而,目前甲基磺酸亚锡的制备方法存在污染环境、产品质量差、收率低等问题。因此,研发新的甲基磺酸亚锡合成方法对其生产及实际应用具有重要意义。基于甲基磺酸亚锡的现状及电解法高效环保、投资省、效益高、应用广的优势,本文提出一种将电解法应用于制备甲基磺酸亚锡的设计思想。以金属锡板为阳极、石墨为阴极,甲基磺酸为阴极室和阳极室电解液,通过电解使阳极锡融入阳极电解液与甲基磺酸根结合,从而实现了电解法制备甲基磺酸亚锡。结合均匀设计及单因素实验设计方法,探讨了电解法制备甲基磺酸亚锡的最佳制备条件;对比研究了电解法和传统化学法所制备甲基磺酸亚锡的稳定性;考察了抗氧化剂提高甲基磺酸亚锡稳定性的可行性;并通过电化学法对阳极锡的溶解行为进行了初步研究。结果表明,电解法制备甲基磺酸亚锡的较优制备条件为MSA为1.5mol·L~(-1)、电流密度为5.0A·dm~(-2)、体系温度为25℃、搅拌速率为400r·min~(-1)、抗氧化剂投加量为2.5g·L~(-1),相应的收率为99.4%。IR分析表明该条件下所得产品为甲基磺酸亚锡。通过均匀实验数据的回归分析,建立了转化率Y和与主要制备影响因素MSA浓度X_1、电流密度X_2、体系温度X_3和搅拌速率X_4间的回归方程:Y=55.2955+16.8906X_2+0.0389X_3-0.0069X_4-1.8886X_1X_2-1.6687X_2X_2+0.0167X_1X_4 -0.00025884X_3X_4,得到了各影响因素的主次顺序为“电流密度电解质浓度搅拌速率体系温度”,且MSA浓度与电流密度之间、MSA浓度与搅拌速率之间、体系温度与搅拌速率之间均存在相互作用。稳定性对比实验表明,电解法制备甲基磺酸亚锡的热稳定性及抗氧化性均明显优于传统化学法所制备的甲基磺酸亚锡,但二者均会产生溶液变色现象。通过Sn2+水解及氧化实验,揭示了温度和酸度是影响甲基磺酸亚锡溶液变色现象的主要因素,而通过加入对苯二酚作为抗氧化剂可明显减缓甲基磺酸亚锡溶液变色现象的产生。经电化学测试的Tafel曲线及电解实验结果,揭示了电解法制备甲基磺酸亚锡的阳极锡的溶解速率随着电解液酸度、温度、搅拌速率的增加而增加,这主要归因于提高酸度会促进溶液中自由离子移动及电荷传递,升高温度引起活化分子比例增加且分子运动速度加快,增加搅拌速率可消除由浓度梯度而导致的浓差极化并加快液相传质速率。由阿累尼乌斯公式计算出反应表观活化能Ea为1.44kJ·mol~(-1)(293.15K~323.15K),由塔菲尔公式得出表观传质系数β为0.22、交换电流密度i0为1.012×10~(-3)A·cm~(-2)。
[Abstract]:With the rapid development of industry, people pay more and more attention to the safety of plating solution, stability and environmental protection. Methyl sulfonic acid tin plating solution is not only stable, low toxicity, low corrosion, high coating quality, can operate under high current density, and the biodegradability of sulfate and carbon dioxide, more environmentally friendly, so the industrial development potential is obvious. However, the preparation process of stannous methanesulfonate in environmental pollution, poor product quality, low yield. Therefore, the development of a new synthesis method of stannous methanesulfonate on its production and application has important significance.
The status quo of stannous methanesulfonate and electrolytic method based on efficient environmental protection, saving investment, high efficiency, wide application, the paper proposes a design idea of electrolysis was applied to the preparation of stannous methanesulfonate. Using metal tin plate as anode and graphite as cathode, methyl sulfonic acid as the cathode chamber and the anode chamber through the electrolyte. The anode electrolytic tin into the anode electrolyte with methyl sulfonic acid radical, so as to realize the electrolytic preparation of stannous methanesulfonate. Combined with uniform design and single factor experimental design method, discusses the conditions for preparation of electrolytic preparation of stannous methanesulfonate was optimized; a comparative study of the electrolytic method and traditional chemical method for preparing methyl sulfonic acid stability stannous; investigated the feasibility of improving the antioxidant stability of stannous methanesulfonate; and studied the electrochemical dissolution behavior of tin anode.
The results show that the electrolytic preparation of stannous methanesulfonate is the optimum preparation conditions of MSA 1.5mol L~ (-1), current density of 5.0A - dm~ (-2) system, the temperature is 25 DEG C, stirring rate of 400R - min~ (-1), antioxidant dosage was 2.5G - L~ (-1). The analysis showed that the product yield of 99.4%.IR under the condition of the stannous methanesulfonate. Even through the regression analysis of experimental data, set up the conversion rate of Y and the main influencing factors of preparation of MSA concentration X_1, current density X_2, temperature X_3 and stirring rate X_4 regression equation between Y=55.2955+ 16.8906X_2+0.0389X_3-0.0069X_4-1.8886X_1X_2-1.6687X_2X_2+0.0167X_1X_4 -0.00025884X_3X_4, has been the order of the influencing factors for the current density, electrolyte concentration, stirring rate and temperature system "between MSA concentration and current density, MSA concentration and stirring rate, temperature and stirring speed system There are interactions between rate. Experiments show that the stability and preparation of stannous methanesulfonate prepared by thermal stability and oxidation resistance of electrolytic preparation of stannous methanesulfonate was significantly better than the traditional chemical method, but the two will produce solution discoloration by Sn2+ hydrolysis and oxidation experiments revealed that the temperature and acidity is the main factors affecting the stannous methanesulfonate solution discoloration, and by adding hydroquinone as antioxidants could alleviate stannous methanesulfonate solution discoloration phenomenon. The Tafel curve and electrochemical electrolysis experimental results reveal the dissolution rate of tin anode electrolytic preparation of stannous methanesulfonate as the electrolyte acidity, temperature increase the stirring rate increased, this is mainly attributed to the increased acidity will promote the transfer of free ions in the solution and mobile charge, high temperature resulted in activation of molecular ratio Increased and molecular motion speed, increasing the stirring rate can eliminate the concentration polarization caused by concentration gradient and speed up the liquid mass transfer rate. By Arrhenius formula to calculate the activation energy for Ea 1.44kJ mol~ (-1) (293.15K~323.15K), by the Tafel formula to the apparent mass transfer coefficient is 0.22, exchange the current density of I0 is 1.012 * 10~ (-3) A - cm~ (-2).

【学位授予单位】：沈阳理工大学
【学位级别】：硕士
【学位授予年份】：2010
【分类号】：TQ134.32

【参考文献】