NiMoRe/HZSM-5催化剂的制备及其催化脂肪酸甲酯加氢脱氧

Preparation of NiMoRe/HZSM-5 Catalyst for Hydrodeoxygenation of Fatty Acid Methyl Ester

使用浸渍法制备了5 kg NiMoRe/HZSM-5催化剂,结合X射线衍射(XRD)、扫描电子显微镜(SEM)、电感耦合等离子原子发射光谱(ICP-OES)等表征手段对催化剂进行理化性质分析,并对该催化剂用于硬脂酸甲酯加氢脱氧反应的最佳条件进行探究。研究结果表明:相比3种商用催化剂,NiMoRe/HZSM-5中金属Ni具有较小颗粒,且分散均匀,BET比表面积(S_(BET))更大,为239.1 m^(2)/g,具有更好的催化活性。在温度260℃、0.3 g催化剂用量、反应时间4 h、初始H 2压力3 MPa的最优反应条件下,原料转化率和烷烃选择性均为100%,且催化剂稳定性较佳,第5次循环原料转化率仍高达96.1%,加氢脱氧(HDO)反应的选择性(S HDO/DCO),即HDO反应与脱羧脱羰(DCO)反应的比值由1.2降至0.56。将催化剂NiMoRe/HZSM-5用于脂肪酸甲酯无溶剂条件下的加氢脱氧反应放大实验后进行中试,采用2.8 L固定床对25 kg脂肪酸甲酯进行连续加氢性能评价,经过15循环后脂肪酸甲酯的转化率达到98%。

A 5 kg NiMoRe/HZSM-5 catalyst was prepared by impregnation method,and the physicochemical properties of the catalyst were analyzed using characterization techniques such as X-ray diffraction(XRD),scanning electron microscopy(SEM),and inductively coupled plasma optical emission spectrometry(ICP-OES).The optimal conditions for the catalyst in the hydrogenation deoxygenation reaction of stearic acid methyl ester were explored.The research results showed that,compared to three commercial catalysts,the metal nickel in NiMoRe/HZSM-5 had smaller and more uniformly dispersed particles,a larger BET specific surface area(S_(BET))of 239.1 m^(2)/g,and exhibited better catalytic activity.Under the optimal reaction conditions of 260℃,catalyst dosage of 0.3 g,reaction time of 4 hours,and initial H_(2) pressure of 3 MPa,both the raw material conversion rate and alkane selectivity were 100%.The catalyst demonstrated good stability,with a high raw material conversion rate of 96.1%even after the 5th cycle,and the ratio of hydrogenation deoxygenation(HDO)reaction to decarboxylation/decarbonylation(DCO)reaction decreased from 1.2 to 0.56.After scaling up the hydrogenation deoxygenation reaction of fatty acid methyl ester under solvent-free conditions using the NiMoRe/HZSM-5 catalyst,a pilot-scale evaluation was conducted on 25 kg of fatty acid methyl ester in a 2.8 L fixed bed reactor.After 15 cycles,the fatty acid methyl ester achieved a conversion rate of 98%.