School of chemistry and chemical engineering,Chongqing University of science and technology
Master innovation program of Chongqing Institute of science and technology（YKJCX2120533和YKJCX2120519）
以鎳為金屬節點，腺嘌呤和檸檬酸為有機配體，采用溶劑熱法制備非晶態金屬有機配合物Ni-A-CA。將PdCl2溶液浸漬于載體Ni-A-CA后用NaBH4還原制得高分散的Pd納米粒子（Pd NPs）催化劑Pd/Ni-A-CA。通過XRD、TEM、XPS等對催化劑的結構、形貌以及組成進行表征分析。結果表明：Pd NPs高度分散在載體Ni-A-CA上，其粒徑為2.2 ± 0.3 nm，且載體與Pd NPs之間存在強的相互作用，增強了催化劑的催化性能。在90 ℃，2 MPa H2條件下，負載量為3%（以Ni-A-CA的質量計，下同）Pd/Ni-A-CA催化劑催化喹啉加氫反應70 min，喹啉轉化率為99%，生成1,2,3,4-四氫喹啉選擇性大于99%。催化劑3% Pd/Ni-A-CA經過5次循環后，其催化性能基本保持不變。
The amorphous metal-organic compounds (Ni-A-CA) were prepared by combining nickel node with organic ligands (adenine (A) and citric acid (CA)) via solvothermal method. Then, highly dispersed Pd/Ni-A-CA catalysts developed were fabricated by dispersing PdCl2 on amorphous support and reducing PdCl2 solution via freshly prepared NaBH4. The microstructure, morphology, and compositions of the obtained Pd/Ni-A-CA catalysts were comprehensively investigated by XRD, FT-IR, TEM, and XPS, etc. The results showed that Pd NPs were in high dispersed state and Pd NPs size diameter was 2.2 ± 0.3 nm. Besides, there existed a strong interaction effect between Pd NPs and amorphous Ni-A-CA support. The optimal temperature and hydrogen pressure were 90 °C and 2 MPa H2, respectively. Under this condition, the conversion of quinoline and the selectivity of 1,2,3,4-tetrahydroquinoline were about 99% over 3% Pd/Ni-A-CA catalyst for 70 min reaction duration. Furthermore, the Pd/Ni-A-CA catalyst also exhibited good catalytic stability and catalytic performance basically kept unchanged after 5 cycles.