Simulation Optimization Of Adsorption And Removal Of Nitrides From Oil By Modified Y Zeolite

In the thesis firstly the same Si O2/Al2O3=5.3 Y zeolites(Na Y,Ag Y,Zn Y,Ni Y,Cr Y,Ce Y)were prepared by using experiments.The N2 adsorption-desorption measurements showed that 6 kinds Y zeolite adsorption stripping curve are?types.But after modified by different metal cations,the specific surface area,pore volume and pore size,are changed than Na Y powder.The order of specific surface area,pore volume and pore diameter of the six kinds of Y zeolite is Cr Y>Ce Y>Zn Y>Ni Y>Na Y>Ag Y.Then,Materials Studio software,work Density Functional Theory(DFT),Grand Canonical Ensemble Monte Carlo(GCMC)method were used in this paper.The mechanism of adsorption and removal of nitrogenous(quinoline,pyrrole,indole,carbazole,and aniline)by six kinds of Y zeolite was simulated and studied.The XRD patterns of the modified Y zeolite were compared with those of the simulated Y zeolite,and the main characteristic peaks of the two zeolites corresponded to each other which indicated that the modified Y zeolite model was reliable and reasonable.On this foundation,the adsorption sites between quinoline,pyrrole,indole,carbazole,aniline and the modified zeolite Y were simulated calculation,the results showed that these adsorption sites were II and III position location in modified zeolite Y cage.The results showed that the order of the electrophilicity of 6 zeolites was Ce Y>Ag Y>Cr Y>Ni Y>Zn Y>Na Y which indicated that the adsorption activity was also Ce Y>Ag Y>Cr Y>Ni Y>Zn Y>Na Y.The front-line orbital analysis of the nitrides quinoline,pyrrole,indoles,carbazole,and aniline showed that the chemical adsorption of the modified Y zeolite to pyrrole,indoles,and aniline was mainly coordination complex adsorption,the distance between the molecules is?~5configuration than?~1N which showed that the stability of the?~5 is greater than the?~1N,the adsorption configurations beween nitrogen compounds and modified Y zeolite were mainly composed of?~5 configuration.The 12T cluster model of modified Y zeolite was analyzed for charge distribution,and it was found that the charge size of the metal atoms on the 6 kinds of Y zeolite was Ce>Ag>Cr>Ni>Zn>Na.The results were consistent with the adsorption energy and charge distribution analysis,the adsorption denitrification capacity of zeolites was Ce Y>Ag Y>Cr Y>Ni Y>Zn Y>Na Y.The adsorption isotherm of quinoline was simulated and calculated respectively by using Na Y,Ag Y,Zn Y,Ni Y,Cr Y and Ce Y zeolite as adsorbents.The results showed that the order of adsorption capacity was:Ce Y>Ag Y>Cr Y>Ni Y>Zn Y>Na Y.The adsorption isotherm of 5kinds of nitrides,such as quinoline,pyrrole,indoles,carbazole and aniline on Ce Y zeolite was simulated,and the order of adsorption saturation capacity of 5 kinds of nitride on Ce Y zeolite was obtained as follows:carbazole>pyrrole>quinoline>aniline>indole.Langmuir adsorption model was used to fit the adsorption isotherms of nitrides on Ce Y zeolite,and the correlation coefficients of the five adsorption isotherms were all greater than 0.99,indicating that the adsorption of nitrides on Ce Y zeolite was monolayer adsorption.The thermodynamic and kinetic analysis of the adsorption process of nitride by modified Y zeolite shows that the adsorption reaction is a spontaneous endothermic entropy increasing reaction.The adsorption process conforms to the quasi-second order equation,and the chemisorption is the control step.