Removal of particulates in slurry oil (SO) from the fluid catalytic cracking process is a challenging task in refining. In this study, we investigate the intrinsic characteristics of particulates in SO and the effect of thermal treatment on their flocculation and further separation. The particulates in SO were characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, etc. Results show that the particulates in SO are composed of coke powders and catalyst powders coated with coke species, with diameters of approximately 1 μm dominating the particle size distribution. The solid contents of middle fractions depend upon thermal treating severities. The particulates are originally dispersed in SO, whereas flocculation of particulates is observed after thermal treatment. A negative linear correlation is found between the solid contents of middle fractions and the asphaltene contents of thermally treated SOs under different thermal treating severities. The mechanism of particle growth as a result of flocculation of particulates with asphaltenes, which favors efficient removal of particulates, is proposed.

中文翻译：

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催化裂化浆液中颗粒的絮凝：颗粒的表征及热处理对其絮凝的影响

从流化催化裂化工艺中去除淤浆油（SO）中的微粒是精炼中的一项艰巨任务。在这项研究中，我们调查了SO中颗粒的内在特征以及热处理对其絮凝和进一步分离的影响。SO中的颗粒通过扫描电子显微镜，能量色散X射线光谱，傅立叶变换红外光谱等进行表征。结果表明，SO中的颗粒由焦炭粉和涂有焦炭物质的催化剂粉末组成，直径约为1微米占主导地位的粒度分布。中级馏分的固体含量取决于热处理的强度。颗粒最初分散在SO中，而热处理后观察到颗粒的絮凝。在不同的热处理强度下，中间馏分的固体含量与热处理过的SOs的沥青质含量之间呈负线性关系。提出了由于沥青质使颗粒絮凝而导致的颗粒生长的机理，这有利于有效去除颗粒。