Hernández-Fernández Joaquín, Puello-Polo Esneyder, Marquez Edgar
Chemistry Program, Department of Natural and Exact Sciences, University of Cartagena, San Pablo Campus, Cartagena 130015, Colombia.
Chemical Engineering Program, School of Engineering, Universidad Tecnológica de Bolivar, Parque Industrial y Tecnológico Carlos Vélez Pombo Km 1 Vía Turbaco, Cartagena 130001, Colombia.
Polymers (Basel). 2024 Feb 23;16(5):605. doi: 10.3390/polym16050605.
This study outlines the investigation into how the compounds CO, CO, and O interact with the active center of titanium (Ti) on the surface of MgCl and how these interactions impact the productivity of the Ziegler-Natta catalyst, ultimately influencing the thermal stability of the produced polypropylene. The calculations revealed that the adsorption energies of Ti-CO-CO and O were -9.6, -12.5, and -2.32 Kcal/mol, respectively. Using the density functional theory in quantum calculations, the impacts of electronic properties and molecular structure on the adsorption of CO, O, and CO on the Ziegler-Natta catalyst were thoroughly explored. Additionally, the Gibbs free energy and enthalpy of adsorption were examined. It was discovered that strong adsorption and a significant energy release (-16.2 kcal/mol) during CO adsorption could explain why this gas caused the most substantial reductions in the ZN catalyst productivity. These findings are supported by experimental tests showing that carbon monoxide has the most significant impact on the ZN catalyst productivity, followed by carbon dioxide, while oxygen exerts a less pronounced inhibitory effect.
本研究概述了对化合物CO、CO₂和O与MgCl₂表面钛(Ti)活性中心相互作用的研究,以及这些相互作用如何影响齐格勒-纳塔催化剂的生产率,最终影响所生产聚丙烯的热稳定性。计算结果表明,Ti-CO、CO₂和O的吸附能分别为-9.6、-12.5和-2.32千卡/摩尔。利用量子计算中的密度泛函理论,深入探讨了电子性质和分子结构对CO、O和CO₂在齐格勒-纳塔催化剂上吸附的影响。此外,还研究了吸附的吉布斯自由能和焓。研究发现,CO吸附过程中的强吸附和大量能量释放(-16.2千卡/摩尔)可以解释为什么这种气体导致ZN催化剂生产率下降幅度最大。实验测试支持了这些发现,表明一氧化碳对ZN催化剂生产率影响最大,其次是二氧化碳,而氧气的抑制作用则不太明显。