氢型无粘结剂丝光沸石催化乙醇胺氨化制备乙二胺

Catalyzed Amination of Ethanolamine to Ethylenediamine over H-Type Binderless Mordenite

摘要:

将硅铝原料与丝光沸石晶种混合成型，对成型前驱体进行水热转化成功制备了c轴方向晶体尺寸为100~200nm的无粘结剂丝光沸石分子筛，通过XRD、TEM、SEM对其进行了表征，结果表明制备的无粘结剂丝光沸石分子筛具有规整的宏观形貌、较高的结晶度和机械强度。基于制备的无粘结剂丝光沸石分子筛，研制了乙醇胺(MEA)催化氨化制乙二胺(EDA)的催化剂。制备的无粘结剂丝光沸石催化剂具有较高的表面酸性以及丰富的孔结构，表现出良好的催化活性和乙二胺选择性。在反应温度为330~340 ℃，乙醇胺液时空速(LHSV)为0.40 h-1, n(NH3)∶n(MEA)= 30，反应压力为1.8 MPa的条件下进行稳定性实验，MEA的单程转化率约50%，EDA选择性大于70%，EDA和哌嗪(PIP)的总收率在40%左右，催化剂运行1400h保持良好的稳定性。再生实验结果表明再生后催化剂活性有较好的恢复。

Abstract:

Binderless mordenite zeolite with small crystal size of 100~200nm in c-axis direction was successfully prepared by a hydrothermal transformation method. The pre-formed precursor of aluminosilicate embedded with mordenite zeolite crystal seeds was converted into binderless mordenite zeolite with regular macro-morphology, high crystallinity and excellent mechanical stability. The catalyst for amination of ethanolamine to prepare ethylenediamine was developed based on the as-prepared binderless mordenite zeolite. The as-prepared catalyst exhibited good catalytic activity and selectivity for ethylenediamine due to high surface acidity and abundant porosity. At the reaction temperature 330~340 ℃, ethanolamine LHSV 0.40 h-1, n (NH3): n (MEA) =30, reaction pressure 1.8MPa, the catalyst stability test indicated that single pass conversion of MEA is about 50% and EDA selectivity is more than 70%, the total yield of EDA and PIP is about 40%. The catalyst remained stable for 1400 hours at the optimum reaction conditions. The activity of the catalyst recovered well after regeneration.