Kinetics Of Catalytic Reaction Of C5 Olefins

With the rapid development of ethylene industry in China,C5 olefins as an important by-product of ethylene cracking,play a pivotal role in the field of fine chemicals.However,the utilization of C5 olefins in China is still in a small scale,high energy consumption,and low utilization rate.In this thesis,1-pentene was used as the carbon pentaolefin model reactant,and the catalytic performance and reaction kinetics of 1-pentene on Ni/Al2O3-TiO2 catalyst were studied in detail,in order to provides a reliable theoretical basis for reactor design of hydrogenation to produce high-quality saturated alkanes by C5 olefins and optimization of operating conditions.The main research tasks includes the following four aspects.(a)The catalyst composition and structure are characterized by XRF,XRD,BET,SEM,TEM and XPS techniques.The catalyst is a supported metal catalyst with TiO2 modified ?-Al2O3 as a carrier and Ni as a main active component.The specific surface area of the carrier is 125 m2/g,and the pore size distribution range is 5-15 nm,which is a mesoporous feature.At the same time,TiO2 and Ni can interact each other,which increases the dispersion of Ni on the surface of the carrier.The acid amount of the catalyst was 0.652 mmol/g,and the acidity was mainly weak acid.(b)According to process parameters of Ni/Al2O3-TiO2 catalyst provided by the cooperation unit,the performance of the catalyst is evaluated.The results show that the conversion of 1-pentene is about 100%.The deactivation behavior of Ni/Al2O3-TiO2 catalysts comprehensively is studied under high space velocity conditions.It is beneficial to maintain the reactivity of fresh Ni/Al2O3-TiO2 under the conditions of high temperature,low pressure and high hydrogen to oil ratio.(c)The effect of operating conditions on the catalytic performance of 1-pentene on Ni/Al2O3-TiO2 was investigated by single factor experiment.The results show that increasing the temperature can increase the conversion of 1-pentene,and the selectivity of the isomer product increases more than the selectivity of the hydrogenation product.Increasing pressure and hydrogen to oil ratio can increase 1-pentene conversion and n-pentane selectivity.Increasing the reaction space velocity results in a decrease in 1-pentene conversion,but has a lower impact on product selectivity.(d)Under the reaction conditions of a temperature of 80-140?,a pressure of 2-3 MPa,a space velocity of 40-100(ml/g.h)and a hydrogen to oil ratio of 600,intrinsic kinetic data is obtained.And based on the power function and the Langmuir-Hinshelwood model,the kinetic equations of four 1-pentene catalytic reaction systems were established.Using MATLAB software,Levenberg-Marquardt optimization method are used to solve the parameter values of the kinetic equations,and finally the kinetic equations of the three products in the 1-pentene catalytic reaction are obtained.Through the mathematical statistics test,it is more suitable to apply the simplified Langmuir-Hinshelwood single active site model to the 1-pentene catalytic reaction system.