Hydrodearomation Kinetics Of Diesel Oil

The rapid economic development has led to an increasing demand for diesel fuel,which has led to an increasingly serious environmental pollution of engine exhaust.As people’s environmental awareness increases,the requirements for diesel quality are increasingly strict.At present,countries around the world have strict requirements on the cetane number,density and aromatic content of diesel(especially the content of polycyclic aromatic hydrocarbons).The sixth stage of the automotive diesel standard in China stipulates that the mass fraction of polycyclic aromatic hydrocarbons should not be higher than 7%.Since the aromatic content directly affects these properties of diesel,the hydrogenation saturation of aromatic hydrocarbons in diesel fuel has become a technological measure that must be taken to produce high quality diesel.In this paper,the hydrodearomation kinetics of diesel at CoMo/Al2O3,NiMo/Al2O3 and NiMoW/Al2O3 were studied in a high-throughput reactor.Firstly,the effects of reaction temperature,hydrogen partial pressure,hydrogen oil volume ratio and space velocity were systematically investigated.Then,based on the experimental data,a lumped kinetic model considering the influence of competitive adsorption was proposed for the hydroaromatization reaction of diesel oil.Kinetic parameters were determined using Powell optimization algorithm.The model fitting results show that the obtained kinetic model agrees well with the experimental results.Further verification results show that the kinetic model can predict the product distribution of diesel oil hydrodearomatization well and provide technical support for operation optimization.In addition,based on the catalytic performance of different types of catalysts,the model for the grading loading of catalysts were established which can provide guidance for the optimization of catalyst loading.