| Fluid catalytic cracking catalyst residue(FC3R)is the spent catalyst from the process in petroleum refining owing to coke and substantial deposits of heavy metal contaminants such as Ni,Fe,and V.Every year,over 300000 tons of this solid waste,which mainly consists of SiO2 and Al2O3,is discharged from petroleum refineries.It is mainly disposed in landfills,which not only pollutes the soil and groundwater,but also causes a high level of resource waste.C9 petroleum resin is a thermoplastic polymer made from the polymerization of the C9 fraction(which are byproducts from the catalytic cracking of petroleum hydrocarbons during the preparation of ethylene).C9 petroleum resin contains a lot of unsaturated hydrocarbons,and the resin has not been processed is usually yellow or amber and displays some shortcomings such as poor thermal stability,poor oxidation resistance,and poor compatibility.The applications of C9 petroleum resin are limited.Hydrogenation can be used to modify C9 petroleum resin for wider industrial applications.In this paper,an ecological and economical Ni catalyst was prepared using pretreated FC3R(PFC3R)as support and Polyvinyl pyrrolidone(PVP)as a dispersant and successfully used in C9 petroleum resin hydrogenation,thereby providing theoretical basis for the resource utilization of FC3R and the development of high added value C9 petroleum resin.The pretreated fluid catalytic cracking catalyst residue(PFC3R)was obtained after high-temperature roasting,pickling and drying,A Ni-based catalyst(Ni-PVP/PFC3R)with PVP as a dispersant supported in a PFC3R was synthesized.The effect of nickel content and PVP amount during the catalyst preparation on the performance of the catalysts for C9 petroleum resin hydrogenation were investigated.The results showed that the optimized preparation conditions of Ni-PVP/PFC3R catalyst are as follows:nickel content of 12 wt%,PVP amount of 1.5 wt%.For comparison,a Ni catalyst without PVP(Ni/PFC3R)was prepared in the same way.The structures and properties of the supported Ni catalysts were characterized by XRD,SEM,XPS,FTIR,H2-TPR/IPD,BET and TEM,and their catalytic performance in the C9 PR hydrogenation was extensively investigated.It can be seen that FC3R contains kaolin,Y zeolite and Al2O3.After pickling,the specific surface area of spent FCC catalyst increased from 67.97 n2·g-1 to 124.60 m2·g-1.Compared with the Ni/PFC3R,Ni-PVP/PFC3R shows a smaller crystallite size,higher Ni dispersion,and stronger interactions between Ni species and the PFC3R support.The catalytic activity and stability of two kinds of catalysts were investigated.Results showed that the Ni-PVP/PFC3R catalyst exhibit higher activity and stability for C9 petroleum resin hydrogenation than the Ni/PFC3R catalyst.The effects of nickel loading,H2 pressure,temperature,and reaction time for C9 petroleum resin hydrogenation over Ni-PVP/PFC3R were investigated.The bromine number was reduced to 1.25 gBr/100g under the following conditions:nickel content of 12 wt%,PVP amount of 1.5 wt%,temperature of 270 ?,H2 pressure of 8 MPa,and reaction time of 240 min.Bromine number was used to analyze the change of C9 PR under the temperature of 240?270 ? and the pressure of 8 MPa.After eliminating the influence of internal and external diffusion,Levenberg-Marquart method,Matlab program and Origin software were used to estimate the parameters of the power dynamic model of C9 PR hydrogenation.The activation energy of C9 PR hydrogenation over Ni/PFC3R catalyst is 144.72 kJ-mol-1.The most suitable model is ri =3.68×1012 e-14472/RTci1.5.The results of dynamic calculation show that lumped kinetics model is in good agreement with the experimental data and the confidence interval is narrow.F-test showed that the kinetics models are statistically significant. |
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