【作者】 范峥；

【导师】 高新；

【作者基本信息】 西北大学 ， 化学工艺， 2009， 硕士

【摘要】 化学镀镍（electroless nickel plating,简称EN）作为一种新型表面保护和表面强化手段,近年来在国内外得到了越来越多的重视和关注。化学镀镍主要利用金属盐和还原剂在同一溶液中进行自催化氧化还原反应,从而在镀件表面沉积出非晶态镍磷合金。化学镀镍技术自1944年由美国国家标准局的A.Brenner和G.Qiddell发现以来,经过60多年的发展已日趋成熟。由于化学镀镍的不断推广和市场需求的不断扩大,化学镀镍工业的发展十分迅速。因为化学镀镍具有设备简单、操作方便、工艺灵活、镀层均匀、硬度高、耐磨、致密无孔和耐腐蚀性好等独特优点,所以它被广泛地应用于石油化工、机械加工、电子能源、汽车制造和航天航空等诸多高科技领域,是目前发展速度最快的表面处理工艺之一。本研究开发出了一种化学镀镍新配方,并首次利用响应面法（Response SurfaceMethodology,简称RSM）中的Box-Behnken设计原理对酸性化学镀镍工艺中的各个影响因素进行优化。研究表明,在主盐硫酸镍30g/L,复合络合剂中有机酸XD和乳酸分别为10.0g/L、15.0ml/L,缓冲剂醋酸钠20.0g/L、加速剂丙酸8.0ml/L和镀液温度85℃的条件下,选择还原剂次磷酸钠30.3g/L,稳定剂醋酸铅30.2mg/L和镀液pH=4.5可以使得镀层沉积速率高达20.27μm·h^-1,该结果普遍优于国内同类水平。为了解决现有企业施镀过程中镀镍废液造成的各种环境污染等问题,寻求一种既能充分利用资源、又能降低工业生产成本,消除镍、磷污染的有效方法,本研究针对企业生产实际情况,对该企业现有化学镀镍废水处理技术进行了深入的探索和研究,并最终利用响应面法优化得到了处理和回收废液的最佳操作条件。研究表明,当选择反应温度67℃、反应pH=10.2,反应时间1.1h时,镍离子去除率可达99.98%,处理后的废液中残余镍离子浓度仅为0.5145mg/L,远低于国标要求的1.0mg/L。同时,当选择氯化钙60.3g/L,过氧化氢16.5ml/L,反应温度75℃时,处理后的废液中总磷去除率亦可达到99.98%以上,完全可以满足达标排放。更多还原

【Abstract】 As a new means of surface protection and consolidation, EN plating has been attracting more and more and attention at home and abroad in recent years. The main principle of EN is to utilize the autocatalytic redox reaction between metal salts and reductant in the same solution to deposit amorphous nickel-phosphorus alloy in the exterior of workpiece. The technology of EN which invented by A.Brenner and G.Qiddell of American National Standards Institute since 1944 has been growing mature gradually during over 60 years. In virtue of the continuous spread of EN and the constant expand of market demand, the industry of EN developed rapidly. It is widely applied in the hi-tech field of petroleum, chemical engineering, machinery, electronics, automobile, aviation, etc because there are many remarkable advantages such as simple facility, convenient manipulation, flexible technics, symmetrical coating, high hardness, endurance, denseness and corrosion-resistant for EN. EN is considered to be one of surface treatment technology which has grown fastest nowadays.The research develop a new EN formula and optimize diverse factors of acid EN technics using Box-Behnken design of RSM for the first time. The result demonstrates that the coating deposition rate can achieve 20.27μm·h^-1 with 30.3g/L reductant sodium hypophosphite, 30.2mg/L stabilizer lead acetate and 4.5 pH value under the condition of 30g/L main salts nickel sulfate, 10.0g/L organic acid XD and 15.0ml/L lactic acid of complexing agent, 20.0g/L buffer sodium acetate, 8.0ml/L accelerator propionic acid and 85℃temperature in the bath. The experimental data generally precedes domestic similar level.The research do an in-depth study aiming the treatment technology of current exhausted EN bath from the reality of corporation and ultimately optimize the operating condition for recycling treatment by RSM in order to solve the various environmental pollution problems caused by exhausted EN bath from enterprise plating process in the existence and explore an efficient way to take full advantage of resource, reduce the industrial product cost and eliminate pollution of nickel and phosphorus. The result shows that the removal efficiency of nickel ion could approach 99.98% under the condition of 67℃temperature, 10.2 pH value and 1.1h reaction time. The remnant nickel ion concentration of treated exhausted EN which is merely 0.5145mg/L much lower than 1.0mg/L of GB requirement. Simultaneously, the removal efficiency of total phosphorus in treated exhausted EN also could reach 99.98% above and entirely fulfill eligible discharge.更多还原