Ni-Ru双金属复合催化剂催化喹啉水热加氢脱氮反应机理与动力学研究

Mechanism and Kinetics of Quinoline Hydrothermal Denitrogenation Catalyzed by a Ni-Ru Bimetallic Composite Catalyst

为探究生物油中难降解的一类重要含氮物质喹啉在水热条件下的催化加氢脱氮反应的机理,研究了Ni-Ru复合金属催化剂作用下喹啉的转化和产物生成规律。实验结果表明:加入甲酸可获得更高喹啉转化率,而加入气态氢则更有利于生成脱氮产物;苯胺和甲基苯胺是主要的喹啉哌啶环开环物质,2-己烯和甲苯是主要的加氢脱氮产物。通过产物分布规律,获得了喹啉水热加氢脱氮反应网络,并发现喹啉在超临界水条件下的反应符合一级反应规律。通过Weisz-Prater公式计算证明了喹啉在超临界水中的反应不受传质阻力的扩散的影响;催化剂透射电子显微镜(TEM)的表征表明制备的催化剂中Ni-Ru双金属均匀分布在γ-Al_(2)O_(3)载体上,但是部分活性金属在水热条件下出现团聚现象。所得结果对生物油水热加氢脱氮提质研究具有一定的借鉴意义。

In order to obtain the mechanism of catalytic hydrodenitrogenation reaction of quinoline,an important nitrogen-containing substance difficult to degrade in bio-oil,in hydrothermal conditions,the conversion and product distribution of quinoline under the action of Ni-Ru composite metal catalyst were studied.Experimental results showed that:the addition of formic acid induced higher quinoline conversion rate,while adding gaseous hydrogen was more conducive to the formation of denitrification products;aniline and methylaniline were the main ring opening compounds of quinoline piperidine;and 2-hexene and toluene were the main hydrodenitrogenation products.According to the product distribution law,the hydrothermal hydrodenitrogenation reaction network of quinoline was obtained,and it was found that the reaction of quinoline under supercritical water conditions conformed to the first-order reaction rule.The Weisz-Prater formula proved that the reaction of quinoline in supercritical water was not affected by the diffusion of mass transfer resistance.TEM characterization of the catalyst showed that the Ni-Ru bimetallic particles in the prepared catalyst were uniformly distributed on theγ-Al_(2)O_(3) support,but some active metals agglomerated in hydrothermal conditions.