碱木质素胺钯络合物的制备及性能表征

Preparation and Characterization of Alkali Lignin-amine Supported Palladium Complex

采用提纯碱木质素与二乙烯三胺进行Mannich反应,制备了碱木质素胺,然后将碱木质素胺与硝酸钯进行络合反应,以pH值为7的水作为反应溶剂时,产物中钯含量最高,可达6.54mg/g。FT-IR和XPS测试结果表明,碱木质素胺的C-N中的N给出电子与Pd2+之间形成了配位键,生成碱木质素胺钯络合物。将碱木质素胺钯络合物用于催化对甲基硝基苯的加氢还原反应,反应3.5h时,转化率可达99%。

Alkali lignin-amine was synthesized with alkali lignin and diethyenetriamine by Mannich reaction. Alkali lignin-amine supported palladium complex was prepared from alkali/ignin-amine and palladium nitrate by complexation reaction which was carried out in aqueous solution at pH 7. The atomic adsorption spectrometry was used to analyze the palladium content of alkali lignin-amine supported palladium complex, the results showed that the palladium content could reached to 6.54 mg/g. The IR, X-ray and XPS analysis methods were used to analyze and characterize the structure of alkali lignin-amine supported palladium complex. The results indicated that in the process of complexation reaction, palladium ions accepted electrons from primary amine in alkali lignin-amine and formed alkali lignin-amine supported palladium complex. Selective hydrogenation of aromatic nitro compounds was catalyzed by alkali lignin-amine supported palladium complex. It was found that under the conditions of 30℃, reaction time 3.5 h, the conversion rate of aromatic nitro compounds was up to 99%. These results provided a new method for value-added utilization of the alkali lignin.