A novel Mg-Li alloy was treated in a cerium nitrate solution and cerium chemical conversion coating was obtained on the alloy. Then the forming process, structure and corrosion resistance of the coating were investigated. The influential factors of cerium conversion coating were discussed through orthogonal experiments, and the optimum processing parameters were confirmed. XPS spectra displayed that the conversion coating consisted of cerium compounds, and the major component of the protective layer was a mixture of Ce （IV） oxide and Ce （IV） hydroxide. In addition, XRD pattern illustrated that there was crystalline CeO2 in the conversion coating. Analysis by SEM showed that the cerium conversion coating was uniform with a fiber-like morphology. The thickness of the conversion coating was 12 μm. The results of electrochemical potentiodynamic polarization and hydrogen evolution measurement indicated that the cerium conversion coating provided effective protection to the novel Mg-Li alloy.
根据清洁生产的理论与思维模式,对生产双酚芴的传统工艺进行了改进,以强酸性阳离子交换树脂代替传统的催化剂催化合成双酚芴,以沸水代替甲醇水溶液洗涤反应混合物,产生的废液经液液萃取和蒸馏处理,使苯酚等有效组分被回收利用,解决了废液的排放问题,基本实现了双酚芴产品的清洁生产。采用清洁生产工艺生产双酚芴,每生产1 t 产品可从废液中回收1.6 t 苯酚,按30t/a 计算,可节约资金约43.2万元/a。与传统工艺相比,双酚芴的清洁生产工艺在经济效益和环境效益方面有明显优势。
