To deeply understand the effects of support properties on the performance of Mo-based slurry-phase hydrocracking catalysts,four Mo-based catalysts supported on amorphous silica alumina(ASA),γ-Al_(2)O_(3),ultra-stable...To deeply understand the effects of support properties on the performance of Mo-based slurry-phase hydrocracking catalysts,four Mo-based catalysts supported on amorphous silica alumina(ASA),γ-Al_(2)O_(3),ultra-stable Y(USY)zeolite and SiO_(2) were prepared by the incipient wetness impregnation method,respectively,and their catalytic performances were compared in the vacuum residue(VR)hydrocracking process.It is found that the Mo/ASA catalyst exhibits the highest VR conversion among the different catalysts,indicating that both the appropriate amount of acid sites,especially B acid sites and larger mesoporous volume of ASA can enhance the VR hydrocracking into light distillates.Furthermore,Mo catalysts supported on the different supports show quite different product distributions in VR hydrocracking.The Mo/ASA catalyst provides higher yields of naphtha and middle distillates and lower yields of gas and coke compared with other catalysts,it is attributed to the highest MoS_(2) slab dispersion,the highest sulfuration degree of Mo species,and the most Mo atoms located at the edge sites for the Mo/ASA catalyst,as observed by HRTEM and XPS analyses.These features of Mo/ASA are beneficial for the hydrogenation of intermediate products and polycyclic aromatic hydrocarbons to restrict the gas and coke formation.展开更多
In order to develop high-efficiency and low-cost catalyst for the slurry-phase hydrocracking of vacuum residue(VR),the catalyst supported on natural rectorite was prepared,and the effect of calcination modification of...In order to develop high-efficiency and low-cost catalyst for the slurry-phase hydrocracking of vacuum residue(VR),the catalyst supported on natural rectorite was prepared,and the effect of calcination modification of rectorite on the catalyst properties and performance was investigated.The support of rectorite and catalyst were characterized by XRD,FTIR,Py-FTIR,H_(2)-TPR and XPS to examine their structures and properties.The comparative reaction results show that VR conversions for the catalysts supported on calcined rectorite were similar with that on raw rectorite,possibly due to the VR cracking reaction controlled by the thermal cracking following free radical mechanism because of few acid sites observed on the catalysts surface.However,the yields of naphtha and middle distillates for the various catalysts were obviously different,and increased following as Rec-Mo(40.4 wt%)展开更多
Upgrading heavy and residual oils into valuable lighter fuels has attracted much attention due to growing worldwide demand for light petroleum product. This study focused on hydrocracking process for atmospheric resid...Upgrading heavy and residual oils into valuable lighter fuels has attracted much attention due to growing worldwide demand for light petroleum product. This study focused on hydrocracking process for atmospheric residue (AR) of Mongolian crude oil in the first time compared to those of other countries. Residue samples were hydrocracked with a commercial catalyst at 450℃, 460℃, 470℃ for 2 hours under hydrogen pressure of 10 MPa. The AR conversion and yield of light fraction (LF) reached to 90.6 wt% and 53.9 wt%, at 470℃ by the hydrocracking for atmospheric residue of Tamsagbulag crude oil (TBAR). In each sample, the yield of MF was the highest at 460℃ temperature, which is valuable lighter fuel product. The polyaromatic, polar hydrocarbons and sulfur compounds were concentrated in the MF and HF because the large amount of light hydrocarbons produced from TBAR as the increasing of the hydrocracking temperature. The content of n-paraffinic hydrocarbons was decreased in HF of TBAR, on effect of hydrocracking temperature. This result suggests the longer molecules of n-paraffin (С20-С32) in HF were reacted better, than middle molecules of n-paraffin (С12-С20) in MF during the hydrocracking reaction. Because the hydrocarbon components of feed crude oils were various, the contents of n-paraffinic hydrocarbons in MF and HF of TBAR and DQAR were similar, but MEAR’s was around 2 times lower and the hydrogen consumption was the highest for the MEAR after hydrocracking.展开更多
One of the commercial means to convert heavy oil residue is hydrocracking in an ebullated bed. The ebullated bed reactor includes a complex gas–liquid–solid backmixed system which attracts the attention of many scie...One of the commercial means to convert heavy oil residue is hydrocracking in an ebullated bed. The ebullated bed reactor includes a complex gas–liquid–solid backmixed system which attracts the attention of many scientists and research groups. This work is aimed at the calculation of the internal recycle flow rate and understanding its effect on other parameters of the ebullated bed. Measured data were collected from an industrial scale residual hydrocracking unit consisting of a cascade of three ebullated bed reactors. A simplified block model of the ebullated bed reactors was created in Aspen Plus and fed with measured data. For reaction yield calculation, a lumped kinetic model was used. The model was verified by comparing experimental and calculated distillation curves as well as the calculated and measured reactor inlet temperature. Influence of the feed rate on the recycle ratio(recycle to feed flow rate) was estimated. A relation between the recycle flow rate, pump pressure difference and catalyst inventory has been identified. The recycle ratio also affects the temperature gradient along the reactor cascade. Influence of the recycle ratio on the temperature gradient decreased with the cascade member order.展开更多
基金The authors acknowledge National Key Research and Development Program of China(2018YFA0209403)National Natural Science Foundation of China(21908027)Qingyuan Innovation Laboratory Program(00121002)for financing this research.
文摘To deeply understand the effects of support properties on the performance of Mo-based slurry-phase hydrocracking catalysts,four Mo-based catalysts supported on amorphous silica alumina(ASA),γ-Al_(2)O_(3),ultra-stable Y(USY)zeolite and SiO_(2) were prepared by the incipient wetness impregnation method,respectively,and their catalytic performances were compared in the vacuum residue(VR)hydrocracking process.It is found that the Mo/ASA catalyst exhibits the highest VR conversion among the different catalysts,indicating that both the appropriate amount of acid sites,especially B acid sites and larger mesoporous volume of ASA can enhance the VR hydrocracking into light distillates.Furthermore,Mo catalysts supported on the different supports show quite different product distributions in VR hydrocracking.The Mo/ASA catalyst provides higher yields of naphtha and middle distillates and lower yields of gas and coke compared with other catalysts,it is attributed to the highest MoS_(2) slab dispersion,the highest sulfuration degree of Mo species,and the most Mo atoms located at the edge sites for the Mo/ASA catalyst,as observed by HRTEM and XPS analyses.These features of Mo/ASA are beneficial for the hydrogenation of intermediate products and polycyclic aromatic hydrocarbons to restrict the gas and coke formation.
基金National Key Research and Development program(2018YFA0209403)National Natural Science Foundation of China(Youth)program(21908027)for financing this research。
文摘In order to develop high-efficiency and low-cost catalyst for the slurry-phase hydrocracking of vacuum residue(VR),the catalyst supported on natural rectorite was prepared,and the effect of calcination modification of rectorite on the catalyst properties and performance was investigated.The support of rectorite and catalyst were characterized by XRD,FTIR,Py-FTIR,H_(2)-TPR and XPS to examine their structures and properties.The comparative reaction results show that VR conversions for the catalysts supported on calcined rectorite were similar with that on raw rectorite,possibly due to the VR cracking reaction controlled by the thermal cracking following free radical mechanism because of few acid sites observed on the catalysts surface.However,the yields of naphtha and middle distillates for the various catalysts were obviously different,and increased following as Rec-Mo(40.4 wt%)
文摘Upgrading heavy and residual oils into valuable lighter fuels has attracted much attention due to growing worldwide demand for light petroleum product. This study focused on hydrocracking process for atmospheric residue (AR) of Mongolian crude oil in the first time compared to those of other countries. Residue samples were hydrocracked with a commercial catalyst at 450℃, 460℃, 470℃ for 2 hours under hydrogen pressure of 10 MPa. The AR conversion and yield of light fraction (LF) reached to 90.6 wt% and 53.9 wt%, at 470℃ by the hydrocracking for atmospheric residue of Tamsagbulag crude oil (TBAR). In each sample, the yield of MF was the highest at 460℃ temperature, which is valuable lighter fuel product. The polyaromatic, polar hydrocarbons and sulfur compounds were concentrated in the MF and HF because the large amount of light hydrocarbons produced from TBAR as the increasing of the hydrocracking temperature. The content of n-paraffinic hydrocarbons was decreased in HF of TBAR, on effect of hydrocracking temperature. This result suggests the longer molecules of n-paraffin (С20-С32) in HF were reacted better, than middle molecules of n-paraffin (С12-С20) in MF during the hydrocracking reaction. Because the hydrocarbon components of feed crude oils were various, the contents of n-paraffinic hydrocarbons in MF and HF of TBAR and DQAR were similar, but MEAR’s was around 2 times lower and the hydrogen consumption was the highest for the MEAR after hydrocracking.
基金supported by the Grant APVV-15-0148 provided by the Slovak Research and Development Agency
文摘One of the commercial means to convert heavy oil residue is hydrocracking in an ebullated bed. The ebullated bed reactor includes a complex gas–liquid–solid backmixed system which attracts the attention of many scientists and research groups. This work is aimed at the calculation of the internal recycle flow rate and understanding its effect on other parameters of the ebullated bed. Measured data were collected from an industrial scale residual hydrocracking unit consisting of a cascade of three ebullated bed reactors. A simplified block model of the ebullated bed reactors was created in Aspen Plus and fed with measured data. For reaction yield calculation, a lumped kinetic model was used. The model was verified by comparing experimental and calculated distillation curves as well as the calculated and measured reactor inlet temperature. Influence of the feed rate on the recycle ratio(recycle to feed flow rate) was estimated. A relation between the recycle flow rate, pump pressure difference and catalyst inventory has been identified. The recycle ratio also affects the temperature gradient along the reactor cascade. Influence of the recycle ratio on the temperature gradient decreased with the cascade member order.
