镧对吗啉催化剂的改性及合成吗啉工艺条件优化

以镍基催化剂为主体,镧为助剂,采用共沉淀法制备负载型镍基催化剂,并用于二甘醇合成吗啉工艺。结果表明,向镍基催化剂中加入物质的量分数为1.0%的镧,在反应温度215℃和反应压力1.0 MPa条件下合成吗啉,吗啉收率提高18.89个百分点,二甘醇转化率提高4.27个百分点,吗啉选择性提高15.29个百分点。通过SEM、BET、BJH和DSC-TG手段对负载型镍基催化剂进行表征,考察助剂镧加入量、反应温度和反应压力对二甘醇合成吗啉的影响。最优条件为:负载助剂镧物质的量分数为1.0%的镍基催化剂用量为反应物质量的0.5%,反应温度205℃,反应压力1.0 MPa,此条件下,吗啉收率达99.81%,二甘醇转化率100%,吗啉选择性99.81%。

Modification of the catalyst by lanthanum and process conditionoptimization for morpholine synthesis

Using lanthanum as the additive,the nickel-based catalysts were prepared by the coprecipitation method and were applied in synthetic process of morpholine from diethylene glycol.The results indicated that morpholine yield,diglycol conversion and the selectivity to morpholine increased by 18.89%,4.27%,and 15.29%,respectively under the condition of lanthanum molar fraction 1.0%,reaction temperature 205 ℃ and reaction pressure 1.0 MPa.The catalysts were characterized by SEM,BET,BJH,and DSC-TG.The catalytic performance of the catalysts for synthetic process of morpholine from diethylene glycol was investigated in a stainless steel autoclave at (0.3-2.2) MPa and (180-220) ℃.The results showed that morpholine yield of 99.81%,diglycol conversion of 100%,and the selectivity to morpholine of 99.81% were attained under the optimal condition as follows:lanthanum molar fraction 1.0%,catalyst dosage 0.5% of reactant mass,reaction temperature 205 ℃ and reaction pressure 1.0 MPa.