Within the refining and coal-chemical production chain, feedstock purification serves as a prerequisite core link to ensure stable operation of downstream units. Hydrocarbon feedstocks contain organosulfur components with complex chemical forms. Such impurities poison catalysts in subsequent processes and lead to degradation and deactivation of catalytic activity. Despite continuous optimization of upstream pretreatment processes, conventional purification methods can hardly remove chemically stable organosulfur species completely. Poor sulfur control in feedstocks not only accelerates catalyst consumption but also aggravates corrosion of process equipment. Enterprises are forced to adopt multiple purification procedures, which brings practical challenges including higher capital investment for equipment and increased energy consumption during daily operation.
Organosulfur hydroconversion technology breaks the performance limits of traditional physical-adsorption desulfurization and enables upgrading of feedstock purification processes. Based on hydrogenation catalytic reactions, this technology converts various organosulfur compounds in feedstocks into readily removable hydrogen sulfide (H₂S), achieving high-efficiency organosulfur conversion from the perspective of reaction mechanism. Nevertheless, practical industrial working conditions feature complex system compositions. Co-existence of hydrocarbons, hydrogen and multiple sulfur-bearing impurities tends to trigger side reactions such as olefin hydrogenation saturation and hydrocarbon cracking, resulting in loss of valuable feedstock and directly lowering overall production economic benefits.
Side reactions take place simultaneously while organosulfur compounds undergo hydrocracking during the reaction process. To achieve satisfactory feedstock purification performance, it is essential to maximize the efficiency of target main reactions and restrain undesirable side reactions. For catalysts, a wide operating condition adaptability window is required to mitigate side-reaction risks. Catalysts shall guarantee high organosulfur conversion efficiency while maintaining favorable reaction selectivity to minimize by-product formation. Meanwhile, catalysts need superior comprehensive mechanical properties, including high compressive strength and low attrition rate. These features fit industrial reactor loading and working conditions with continuous high-velocity gas flow erosion, supporting long-term uninterrupted operation of the whole plant.
The hydroconversion catalyst developed by Shandong Xunda Chemical Industrial Group Co., Ltd. adjusts the rate ratio of different reaction pathways under real-world industrial conditions and suppresses side reactions induced by excessive hydrogenation. It balances organosulfur conversion efficiency and reaction selectivity, and is widely applicable to desulfurization scenarios for diverse hydrocarbon gas sources and feed oils in oil refining and coal-chemical industries.