Pd-Fe/MWCNTs双金属催化剂制备及其脱氯动力学  

Preparation and dechlorination kinetics of Pd-Fe/MWCNTs bimetallic catalyst

作　　者：葛伟童 廖亚龙[1] 李明原 嵇广雄 郗家俊 GE Weitong;LIAO Yalong;LI Mingyuan;JI Guangxiong;XI Jiajun(Faculty of Metallurgical and Energy Engineering,Kunming University of Science and Technology,Kunming 650093,Yunnan,China)

机构地区：[1]昆明理工大学冶金与能源工程学院,云南昆明650093

出　　处：《化工进展》2023年第4期1885-1894,共10页Chemical Industry and Engineering Progress

基　　金：国家自然科学基金(21978112);昆明理工大学分析测试基金(20192202030)。

摘　　要：漂白紫胶常用于制药及食品行业,但制备过程中加成到其双键结构的结合氯对其使用领域和性能有负面影响,漂白紫胶中结合氯的脱除研究是紫胶高值利用研究的热点。本文以改性多壁碳纳米管为载体,采用超声强化、液相还原法制备出负载型Pd-Fe双金属催化剂,并用以漂白紫胶的催化加氢脱氯研究,以XRD、XPS、SEM、HRTEM对催化剂进行分析表征。结果表明,制备出的催化剂活性成分粒径为6.32nm,晶格参数为2.27Å;催化剂加氢脱氯反应属于取代反应,过程遵循一级反应动力学,反应的活化能值为23.20kJ/mol;55℃、65℃和75℃对应的反应速率常数分别为0.0267min^(-1)、0.0349min^(-1)和0.0435min^(-1);在最佳的脱氯反应条件下,制备得到的催化剂用于加氢脱除漂白紫胶中结合氯时,脱氯效率达到93.68%,氯质量分数由脱氯前的2.42%降至0.14%。Bleached lac is often used in pharmaceutical and food industry,but the binding chlorine added to its double bond structure in the preparation process has a negative impact on its application and performance.The removal of binding chlorine from bleached lac is a hot spot in the research of high value utilization of lac.In this paper,the supported Pd-Fe bimetallic catalyst was prepared by ultrasonic intensification and liquid reduction method using modified multi-walled carbon nanotubes as the support.The catalytic hydrogenation dechlorination of bleach lac over the supported Pd-Fe bimetallic catalyst was studied,and the prepared catalyst was characterized by XRD,XPS,SEM and HRTEM.The results showed that the particle size and lattice parameters of the prepared catalyst were 6.32nm and 2.27Å,respectively.The hydrogenation dechlorination process belonged to substitution reaction and followed the first-order reaction kinetics.The reaction rate constanted at 55℃,65℃and 75℃are 0.0267min^(-1),0.0349min^(-1)and 0.0435min^(-1),respectively,giving an activation energy of 23.20kJ/mol.Under the optimum reaction conditions,the dechlorination efficiency reaches 93.68%and the chlorine in bleached lac decreased from 2.42%to 0.14%.

关 键 词：催化剂 纳米材料 载体 加氢 反应动力学 

分 类 号：TQ426.82[化学工程]