钯/碳纤维脱氧催化剂高效性原因的初步考察

利用低温氮吸附、热分析、电镜、氢化学吸附和动态分析设备,对钯/碳纤维脱氧催化剂及其载体的性质及行为进行了测量和研究.研究结果表明,钯/碳纤维脱氧催化剂之所以高效,归纳起来主要有两方面的原因:物理方面的原因是纤维催化剂具有比粒状催化剂低得多的传质阻力;化学方面的原因是钯/碳纤维脱氧催化剂上有极强的氢溢流现象存在,以致于有可能使碳纤维中的微孔在催化脱氧反应中起着重要的作用.测量结果也充分地证明了早先理论研究工作中所作假设的可靠性.

Causes for the High Performance of Pd-Carbon Fiber Deoxygenation Catalyst

The properties and behavior of Pd-carbon fiber deoxygenation catalyst and its carrier are measured and studied by employing low temperature N2 adsorption, thermal analysis, electronic macroscope, H2 chemisorption and dynamic analysis.The results show that high performance of Pd-carbon fiber deoxygenation catalyst is responsible for its physical and chemical characteristics. The resistance of mass transfer is much lower for the fiber catalysts than the granular ones. Heavy H2 spillover in the system of H2-Pd-carbon fiber may happen and H2-O2 reaction within the micropore of carbon fibers may possibly occur. The reaction between adsorbed oxygen and spillover hydrogen on the surface of the micropore may play an important role in the deoxygenation process of the fiber catalyst. Results measured comfirmed that the assumptions made in previous theoretical approaches appear to be valid.