苯胺气相缩合制二苯胺稀土改性F~－／γ－Al_2O_3催化剂的研究

Ｆ－／γ－Ａｌ２Ｏ３用于苯胺气相缩合制二苯胺，具有较高的活性，但其稳定性不好，易失活。采用稀土（Ｌａ３＋、Ｃｅ４＋）改性Ｆ－／γ－Ａｌ２Ｏ３，均能使其催化活性和稳定性提高，尤以Ｃｅ４＋效果较佳。活性组份的浸渍顺序对催化剂的活性和稳定性影响较大。用Ｃｅ４＋改性Ｆ－／γ－Ａｌ２Ｏ３后的催化剂，在４２０℃、ＷＨＳＶ＝０．１２ｈ－１时，二苯胺收率在３０％以上的单程寿命超过８０小时。

Study on F-/γ-Al_2O_3 Catalyst Modified by Rare Earth Element for the Vapor-Phase Condensation of Aniline to Diphenylamine

F-/γ-Al2O3 catalyst has higher catalytic activity for the vapor-phase condensation of aniline to diphenylamine. But its stability isn't ideal.However,modification by rare earth element(La3+ 、Ce4+ )can enhance the catalytic activity and stability of F-/γ-Al2O3 catalyst.The sequence of dipping the active ingredients can influence the catalytic activity and stability of the catalyst. The F-/γ-Al2O3 catalyst loaded with Ce4+ has higher activity and stability, under the conditions of 420C and WHSV 0.12h-1,the single-pass life with yields of diphenylamine above 30% is more than 80h.