Adamou Panayiota, Harkou Eleana, Bumajdad Ali, De Jong Xander, Van Haute Maarten, Constantinou Achilleas, Al-Salem Sultan Majed
Department of Chemical Engineering, Cyprus University of Technology, 57 Corner of 6 Athinon and Anexartisias, 3036 Limassol, Cyprus.
Department of Chemistry, Faculty of Science, Kuwait University, P.O. Box 5969, 13060 Safat, Kuwait.
ACS Omega. 2024 Apr 16;9(17):19057-19062. doi: 10.1021/acsomega.3c09729. eCollection 2024 Apr 30.
The dramatic increase in plastics production, coupled with a low recycling and recovery rate, has been a major challenge for sustainable practices and combating climate change. Hydrotreatment processing to upgrade fuel oils is a well-known process in the petroleum industry. In this work, we aim to investigate the catalyst properties before and after the hydrotreatment of pyrolysis oil derived from plastics, namely, linear low-density polyethylene, as no such report is available in the literature. Granular and powder forms of the Pt/AlO catalyst were used in this study with characterization methods executed as such: transmission electron microscopy, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and IR-RIS. XRD data show that the crystallinity of the catalyst support was unaffected by the hydrotreatment without any residues left, as the characteristic diffraction peaks were indicated for the crystalline phase of the support as 37.4, 39.8, 46.3, and 67.3°. In addition, the TGA experiments revealed that the carbon deposition on the spent catalyst was higher, as indicated by the higher weight loss (15.359%) compared to the fresh catalyst sample (11.43%). XPS analysis showed that the carbon deposition is more intense on the granular spent catalyst, as the intensity of the peaks is some 15 times greater than the peaks from the fresh catalyst. Also, compared to the observed peaks of the powder catalyst, less coke is formed. The band at 1624.05 cm from the IR-RIS spectra was attributed to a shifted C=O band from the coke formation. The extension of these investigations using different catalysts to improve their characteristics and performance and to inhibit coke deposition will contribute to the incorporation of such processes in industry as well as the cost of fuels.
塑料产量的急剧增加，再加上低回收利用率，一直是可持续发展实践和应对气候变化的重大挑战。加氢处理工艺用于升级燃料油，这在石油工业中是一个广为人知的过程。在这项工作中，我们旨在研究由塑料（即线性低密度聚乙烯）衍生的热解油加氢处理前后的催化剂性能，因为文献中尚无此类报告。本研究使用了颗粒状和粉末状的Pt/AlO催化剂，并采用了如下表征方法：透射电子显微镜、X射线光电子能谱（XPS）、X射线衍射（XRD）、热重分析（TGA）和红外拉曼光谱（IR-RIS）。XRD数据表明，催化剂载体的结晶度在加氢处理后未受影响，且没有留下任何残留物，因为载体结晶相的特征衍射峰为37.4°、39.8°、46.3°和67.3°。此外，TGA实验表明，与新鲜催化剂样品（11.43%）相比，废催化剂上的积碳更高，这表现为更高的重量损失（15.359%）。XPS分析表明，颗粒状废催化剂上的积碳更为严重，因为其峰强度比新鲜催化剂的峰强度大约高15倍。而且，与粉末催化剂观察到的峰相比，形成的焦炭更少。IR-RIS光谱中1624.05 cm处的谱带归因于焦炭形成导致的C=O谱带位移。使用不同催化剂进行这些研究以改善其特性和性能并抑制焦炭沉积，将有助于此类工艺在工业中的应用以及燃料成本的降低。
