不锈钢和钛在氨汽提法尿素介质中的腐蚀

CORROSION OF STAINLESS STEELS AND TITANIUM IN MEDIA FOR THE AMMONIA STRIPPING UREA PROCESS

用ＳＥＭ、ＸＲＤ和ＸＰＳ等技术研究了３１６Ｌ、２ＲＥ６９和０Ｃｒ１７Ｍｎ１４Ｍｏ２Ｎ（Ａ４）不锈钢及工业纯钛ＴＡ１在氨汽提法尿素合成介质中的耐蚀性．结果表明：在合成塔液相介质中，２ＲＥ６９的耐蚀性最佳．在汽提塔液相介质中，ＴＡ１耐蚀性最佳，２ＲＥ６９也有良好的耐蚀性．这些材料的钝化膜，在合成塔以金属自身的氧化物为主要成分，在汽提塔以沉积物α－Ｆｅ２Ｏ３为主要成分．

The corrosion resistance of 316L, 2RE69 and OCr17Mn14Mo2N(A4) stainless steels and titanium in the media of ammonia stripping urea process were studied by means of SEM, X ray diffraction and XPS. Experimental results indicated that the corrosion resistance of 2RE69 was better than that of the others in the urea reactor solution, while titanium and 2RE69 were better in the stripper solution. The passive films formed on these metals were composed mainly of oxides produced by anodic reaction in the reactor solution and chemical deposits α Fe 2O 3 in the stripper solution.