糠醛抽提预处理催化裂化循环油制备中间相沥青原料

Preparation of mesophase asphalt from furfural extraction pretreatment of catalytic cracking circulating oil

以糠醛作为抽提分离溶剂,以中石油克拉玛依石化有限责任公司100万t/a催化裂化装置的循环油为原料,在实验室考察了催化裂化循环油中的多环短侧链稠环芳烃和少环长侧链的饱和烃的抽提分离及精制预处理情况。结果表明:在抽提温度为60℃,糠醛与催化裂化循环油的质量比为2∶1,停留时间30 min的优化预处理条件下,催化裂化循环油的抽提分离效果较好,同时完全脱除了灰分。催化裂化循环油经糠醛抽提预处理优化精制后,所得抽出油烃族组成中的芳烃质量分数高达80.35%,烃类组成中的总芳烃质量分数高达79.1%,可作为制备可纺织中间相沥青的优质原料;而所得抽余油的密度及含硫、含氮量均较催化循环油的大幅降低,烃族组成中的饱和烃质量分数高达91.45%,烃类组成中的饱和环烷烃和链烷烃质量分数之和高达93.9%,具有良好的催化裂化性能,可返回作为催化裂化装置的优质原料。

Using furfural as the extraction&separation solvent and the circulating oil of the 1 Mt/a fluid catalytic cracking(FCC)unit of Karamay Petrochemical Co Ltd,PetroChina,as the raw material,the cases of extraction,separation and refining pretreatment of the thick polycyclic aromatic hydrocarbons with short side chains and the saturated hydrocarbons with few long side chains in FCC circulating oil were investigated in the laboratory.The results showed that under the optimal pretreatment conditions of the extraction temperature at 60℃,the mass ratio of furfural to FCC circulating oil at 2∶1 and the residence time at 30 min,the extraction pretreatment effect of FCC circulating oil was better,and the ash was completely removed.After FCC circulating oil was optimally refined by furfural extraction pretreatment,the mass fraction of the aromatics of hydrocarbon group composition and the total aromatics of hydrocarbon composition both in the extract oil was up to 80.35%and 79.1%,respectively,which could be used as the high-quality raw materials for preparing the spinnable mesophase asphalt.Meanwhile,the density,sulfur and nitrogen content of the raffinate oil were significantly lower than that of FCC circulating oil.The mass fraction of saturated hydrocarbon in hydrocarbon group composition was as high as 91.45%,and the sum of the mass fraction of saturated naphthene and paraffin in hydrocarbon composition reached 93.9%.Therefore,the raffinate oil had the satisfactory catalytic cracking performance and could be returned as the high-quality raw materials for FCC unit.