常规干燥氧化石墨烯制备高性能Pt加氢催化剂

Preparation of high performance Pt hydrogenation catalysts from conventional dried graphite oxide

采用Hummers法制备了氧化石墨烯(GO),制备过程中分别采用了冷冻干燥和常规干燥(干燥温度分别为60℃和100℃),制得的GO分别记为GO-LT,GO-60,GO-100,并利用乙二醇还原法制备了Pt/rGO(rGO为还原GO)催化剂。采用XRD,FTIR,AFM,XPS,H_(2)-TPR等方法对GO和Pt/rGO进行了表征,并将催化剂用于萘加氢制十氢萘反应,考察了干燥温度对GO和Pt/rGO的结构、物化性质及Pt/rGO加氢脱芳烃催化性能的影响。实验结果表明,干燥温度升高有利于Pt纳米粒子的分散,且能够促进含氧官能团的还原,但容易使石墨层堆叠;Pt/rGO-60催化剂的Pt纳米粒子分散度高,且石墨层没有严重堆叠,因此Pt/rGO-60催化剂的活性和十氢萘选择性明显高于Pt/rGO-LT和Pt/rGO-100,实现了萘的高效深度加氢饱和。

Graphene oxide(GO)was prepared by Hummers method with freeze drying and conventional drying at 60℃and 100℃,the resulting GO were noted as GO-LT,GO-60,and GO-100,respectively.Pt/rGO hydrogenation catalysts were prepared by ethylene glycol reduction method.GO and Pt/rGO were characterized by XRD,FTIR,AFM,XPS,and H2-TPR methods.The catalysts were used for hydrogenation of naphthalene to decalin.The effects of drying temperature on the structure and physicochemical properties of GO and Pt/rGO,and catalytic performance of Pt/rGO for hydrodearomatization were investigated.The experimental results show that the increase of drying temperature is beneficial to the dispersion of Pt nanoparticles and can promote the reduction of oxygencontaining functional groups,but it is easy to stack graphite layers.Pt/rGO-60 has a high dispersion of Pt nanoparticles,and the graphite layer is not seriously stacked.Therefore,the catalytic activity and decalin selectivity of Pt/rGO-60 are significantly higher than those of Pt/rGO-LT and Pt/rGO-100,achieving efficient and deep hydrogenation saturation of naphthalene.