关键词: 重芳烃, 催化裂化, 轻芳烃, 低碳烯烃, 节能降耗

Abstract: In order to efficiently convert heavy aromatics (mainly C₉-C₁₁A) from naphtha distillate into light aromatics without hydrogen consumption, a pilot-scale study on catalytic cracking of heavy aromatics was carried out using heavy aromatics as feedstock in DCC unit. The results indicated that the heavy aromatics were efficiently converted and benzene, toluene, xylene (BTX) and low carbon hydrocarbons were formed under the action of special catalyst A. The conversion rate of heavy aromatics was over 80%, the yield of BTX was over 40%, and the yield of light olefins was about 6% at different reaction temperature; the yield of BTX was the highest at 640 ℃ (43.38%), and the yield of BTX + ethylene and propylene was over 50%. The ratio of BTX could be adjusted within certain range by adjusting the reaction temperature. With the increase of reaction temperature, the yield of benzene and toluene increased, while the yield of xylene decreased. The non-aromatic hydrocarbons in the feed were efficiently converted, and the aromatic hydrocarbons in the gasoline product were highly concentrated. Light aromatics could be produced by distillation without adding a new aromatics extraction unit, which could greatly reduce the energy consumption of BTX production and realize quality improvement and efficiency enhancement in refining and chemical enterprises

Key words: heavy aromatics, catalytic cracking, light aromatics, light olefins, energy saving and emission reduction