Ni/氮掺杂碳催化剂的制备及其催化甲烷干重整实验研究

Preparation of Ni/nitrogen-doped carbon catalysts and their experimental study on dry reforming of methane

以氮掺杂改性碳材料(邻二氮杂菲和三聚氰胺为氮源,毛竹粉为碳源)和富氮碳材料(豆渣)为载体,采用浸渍法制备了一系列含氮的Ni/氮掺杂碳催化剂。主要考察了N物种造成的碳载体结构及Ni与碳载体结合形式的改变对甲烷干重整反应性能的影响。结果表明,相比于未掺氮催化剂,N物种的存在增强了碳载体对Ni的锚定和稳固,掺氮之后Ni实际负载量增加了97%以上。不同氮源的Ni/氮掺杂碳催化剂中,富氮豆渣碳载体制备的催化剂(DC-5%)中N主要以C-N和Ni-Nx形式存在,对甲烷干重整活性最高,CH_(4)和CO_(2)转化率分别达到90%和95%以上。对DC-5%催化剂进行了100 h稳定性测试,整个过程中CH_(4)和CO_(2)的转化率始终维持在80%和90%左右,均未出现明显下降。

A series of nitrogen-containing Ni/nitrogen-doped carbon catalysts were prepared by impregnation method using nitrogendoped modified carbon materials(orthophenanthrolene and melamine as nitrogen sources and bamboo as carbon source) and nitrogenrich carbon materials(soybean residue) as carriers. The effects of the changes of the structure of the carbon carrier caused by N species and the change of the form of Ni binding to the carbon carrier on the performance of the methane dry reforming reaction were mainly investigated. The results show that, compared to the non-nitrogen-doped catalysts, the presence of N species enhances the anchoring and stabilization between Ni and the carbon carriers, and the actual Ni loading increases by more than 97% after nitrogen doping. Among the Ni/nitrogen-doped carbon catalysts with different nitrogen sources, the catalyst prepared from nitrogen-rich soybean residue carbon carrier(DC-5%) with N mainly in the form of C-N and Ni-Nx has the highest activity for dry reforming of methane, reaching over 90% and 95% conversion of CH_(4)and CO_(2), respectively. An 100 h stability test was performed on the DC-5% catalyst, and the conversion rates of CH_(4)and CO_(2)are maintained at about 80% and 90% respectively throughout the process without any significant decrease.