CAJ | 학술논문

为了研究Sn含量和还原温度对Sn-Raney Ni催化剂的物理化学结构和催化分解N,N-二甲基甲酰胺(DMF)活性的影响,利用沉淀法制备了一系列不同Sn含量的Sn-Raney Ni催化剂,采用N_2物理吸附、X射线衍射(XRD)和氢气程序升温还原(H_2-TPR)等方法对不同Sn含量和不同还原温度制得的Sn-Raney Ni催化剂的比表面积、物相组成和还原性能进行了表征.以N,N-二甲基甲酰胺(DMF)为模型化合物,对Sn-Raney Ni催化剂的催化分解活性进行了评价.XRD表征结果表明,n(Sn)/n(Ni)为0.1的催化剂分别在723 K和823 K下还原生成Ni_3Sn_4和Ni_3Sn合金晶相;n(Sn)/n(Ni)为0.15的催化剂在723 K下还原形成Ni_3Sn_2合金晶相.H_2-TPR结果表明,Ni-Sn合金的形成削弱了Sn和Ni与氧的结合能,使得Sn和Ni的还原峰向低温移动.催化分解DMF实验结果表明,当n(Sn)/n(Ni)为0.1、还原温度为723 K时,Sn修饰Raney Ni催化剂能够将高浓度DMF(5%(wt))完全分解(分解率达100%),氢气的选择性达到86.8%.
위료연구Sn함량화환원온도대Sn-Raney Ni최화제적물이화학결구화최화분해N,N-이갑기갑선알(DMF)활성적영향,이용침정법제비료일계렬불동Sn함량적Sn-Raney Ni최화제,채용N_2물리흡부、X사선연사(XRD)화경기정서승온환원(H_2-TPR)등방법대불동Sn함량화불동환원온도제득적Sn-Raney Ni최화제적비표면적、물상조성화환원성능진행료표정.이N,N-이갑기갑선알(DMF)위모형화합물,대Sn-Raney Ni최화제적최화분해활성진행료평개.XRD표정결과표명,n(Sn)/n(Ni)위0.1적최화제분별재723 K화823 K하환원생성Ni_3Sn_4화Ni_3Sn합금정상;n(Sn)/n(Ni)위0.15적최화제재723 K하환원형성Ni_3Sn_2합금정상.H_2-TPR결과표명,Ni-Sn합금적형성삭약료Sn화Ni여양적결합능,사득Sn화Ni적환원봉향저온이동.최화분해DMF실험결과표명,당n(Sn)/n(Ni)위0.1、환원온도위723 K시,Sn수식Raney Ni최화제능구장고농도DMF(5%(wt))완전분해(분해솔체100%),경기적선택성체도86.8%.
In order to investigate the effects of Sn content and reduction temperature on the physicochemical structure of Raney Ni catalysts modified with Sn and their catalytic decomposition performance for DMF, the Raney Ni catalysts with different Sn contents were prepared by precipitation method. N_2 physical adsorption, X-ray diffraction (XRD) and hydrogen temperature programmed reduction (H_2-TPR) were employed to characterize the BET surface areas, phase compositions and reduction behavior of the catalysts containing various Sn contents and reduced under different temperatures. Using DMF as model compound, the catalytic activities of the Sn modified Raney Ni catalysts were examined by the probe reaction of DMF decomposition. The XRD results show that the metallic alloy phases of Ni_3Sn_4 and Ni_3Sn are present in the catalysts with n(Sn)/n(Ni)= 0.1 and reduced at 723 K and 823 K, respectively; while metallic alloy phase of Ni_3Sn_2 is present in the catalyst with n(Sn)/n(Ni)= 0.15 and reduced at 723 K. H2-TPR results indicate that the reduction peak of Sn and Ni shift to lower temperature with the formation of Ni-Sn metallic alloy, which could be attributed to the decrease of the binding energies of Sn and Ni with oxygen. The DMF with high concentration (5%(wt)) in wastewater could be completely decomposed into inorganic molecules over the Sn modified Raney Ni catalyst with n(Sn)/n(Ni)=0.1 and reduced at 723 K, and the H_2 selectivity could reach 86.8%.