Study On Hydrogenation Saturation And Selective Ring Opening Of Diesel Aromatics

With the growing of the environmental pollution and from the stringent requirements for vehicle emissions,is becoming more and more strict in the quality of clean fuel.Catalytic cracking(FCC)diesel is main Secondary processing diesel oil in China,and this kind of oil contains a large number of aromatic,the increase of aromatic content in diesel can reduce oil product quality and cetane number,therefore further reducing aromatics content in diesel oil has become one of the biggest challenges facing during the process of producing clean diesel.Developing and preparing the catalyst of FCC diesel aromatics hydrogenation saturation and selective ring opening,increasing cetane number is an effective way to produce clean FCC diesel by hydro-upgrading.Y zeolite has suitable acidity and unique pore structure,and is widely used in catalytic cracking,hydrocracking and isomerization oil,etc,especially is widely studied in the diesel fraction aromatics hydrogenation ring opening reaction.Due to weak acid and pore structure of Na Y zeolite can not meet the requirement of hydro-upgrading,so it need to be modified.Na Y zeolite was modified by ammonium ion exchange,hydrothermal treatment,oxalic acid treatment in this paper,and prepared a series of modified Y zeolite,used a variety of characterization methods such as XRD,BET,NH3-TPD and IR,studied structure and acid of Y zeolite by using the different methods,and get the best modification conditions.Catalyst carrier is Y zeolite by hydrothermal and oxalic acid modified and pseudo-boehmite,then the as-synthesized catalyst supports depositing with Ni W metal components were prepared as the hydro-upgrading catalysts through impregnation.Give priority to with the catalyst,using FCC slurry oil as raw material,the performance was evaluated in 250 ml high pressure reaction kettle,the effect on the properties of raw oil hydro-upgrading by studing different carrier modified catalysts,the reaction temperature,hydrogen pressure,reaction time and catalyst concentration.The study found that:the Cat-30 catalyst hydrogenation performance is the best,unedr the best condition of the reaction temperature 350℃,hydrogen pressure 10.0Mpa,1h reaction time,catalyst concentration is 4wt %,in the product after the reaction,aromatic content dropped to below 25%,double ring aromatic content dropped to below 5%,increased by about 13 units of cetane number,and make some aromatic hydrogenation saturation open ring.