Six Ni-Mo catalysts with different metal contents were prepared and characterized by N2 adsorption and X-ray diffi＇actometry. The active phase microstructure of these catalysts was examined by the Raman spectroscopy,...Six Ni-Mo catalysts with different metal contents were prepared and characterized by N2 adsorption and X-ray diffi＇actometry. The active phase microstructure of these catalysts was examined by the Raman spectroscopy, temperature- programmed reduction （TPR）, X-ray photoelectron spectroscopy, and high-resolution transmission electron microscopy. Hydrodesulfurization （HDS） activity of catalyst samples were analyzed in a flow fixed-bed microreactor. The sulfidation degree of Mo and the length of the MoS2 slab slightly increased with the amount of metal loaded following sulfidation. This small change is attributed to polymolybdate species observed in all the oxidized catalysts. Weak metal-support interactions, as determined by the TPR technique, increased the NiSx sulfidation phase and MoS2 slab stacking. The HDS activity of the catalyst samples increased with the number of active sites. For high metal loading catalysts, their HDS activity was nearly identical because the sulfur atoms cannot easily approach active sites. This change is caused by the large number of stacked layers in the MoS2 slabs as well as the decrease in the specific surface area and pore volume of the catalyst samples with an increasing metal loading.展开更多
The influence of active metal components of catalyst, additives and catalyst preparation method on the reactivity of catalyst for selective hydrodesulfurization (HDS) of FCC naphtha was investigated, and the RSDS-21 c...The influence of active metal components of catalyst, additives and catalyst preparation method on the reactivity of catalyst for selective hydrodesulfurization (HDS) of FCC naphtha was investigated, and the RSDS-21 catalyst with high HDS performance and the RSDS-22 catalyst with high selectivity were developed by RIPP. The composite loading of a new series of catalysts for selective HDS of FCC gasoline has demonstrated excellent desulfurization activity and selectivity and can under conventional hydrotreating conditions manufacture clean gasoline product meeting the national IV emission standard and the Euro V emission standard with less loss in antiknock index. The finalized new series of FCC catalysts upon being adopted for selective HDS of FCC naphtha have good adaptability to different feedstocks along with good stability.展开更多
More stringent environmental legislation imposes severe requirements to reduce the sulfur content in diesel to ultra-low levels with high efficient catalysts.In this paper,a series of CoMo/NDC@alumina catalysts were s...More stringent environmental legislation imposes severe requirements to reduce the sulfur content in diesel to ultra-low levels with high efficient catalysts.In this paper,a series of CoMo/NDC@alumina catalysts were synthesized by combination of the chemical vapor deposition of nitrogen-doped carbon(NDC)using 1,10-phenanthroline and co-impregnation of Mo and Co active components.The optimal catalyst with additive of 25%1,10-phenanthroline was screened by a series of property characterization and the hydrodesulfrization(HDS)active test.The amount of“CoMoS”active phase of the optimal CoMo/C3 catalyst increased 5.3%as compared with the CoMo/c-Al_(2)O_(3).The introduction of NDC improved the sulfidation degree of Mo by 21.8%as compared to the CoMo/c-Al_(2)O_(3) catalyst,which was beneficial to form more active sites.The HDS conversion of the NDC supported catalysts are higher than CoMo/c-Al_(2)O_(3) whether for the dibenzothiophene(DBT)or 4,6-dimethyl dibenzothiophene(4,6-DMDBT).Further hydroprocessing evaluation with Dagang diesel revealed that the CoMo/C3 catalyst possessed higher HDS property and the removal rate of DBTs in the diesel increased by 4%–11%as compared to the CoMo/c-Al_(2)O_(3) catalyst.展开更多
A series of NiMo/FDU-12 catalysts with tunable pore diameters and mesostructures have been controllably synthesized by adjusting the synthetic hydrothermal temperature and applied for the hydrodesulfurization of diben...A series of NiMo/FDU-12 catalysts with tunable pore diameters and mesostructures have been controllably synthesized by adjusting the synthetic hydrothermal temperature and applied for the hydrodesulfurization of dibenzothiophene and its derivative.The state-of-the-art electron tomography revealed that the pore sizes of FDU-12 supports were enlarged with the increase in the hydrothermal temperature and the mesostructures were transformed from ordered cage-type pores to locally disordered channels.Meanwhile,the MoS2 morphology altered from small straight bar to semibending arc to spherical shape and finally to larger straight bar with the change of support structures.Among them,FDU-12 hydrothermally treated at 150℃possessed appropriate pore diameter and connected pore structure and was favorable for the formation of highly active MoS2 with curved morphology;thus,its corresponding catalyst exhibited the best HDS activity.Furthermore,it was indicated that the isomerization pathway could be significantly improved for HDS of 4,6-dimethyldibenzothiophene after the addition of aluminum,which was expected to be applied to the removal of the macromolecular sulfur compounds.Our study sheds lights on the relationship between support effect,active sites morphology and HDS performance,and also provides a guidance for the development of highly active HDS catalysts.展开更多
A simple method for preparation of presulfided eggshell CoMoS/γ-Al2O3 catalysts with sharp boundary is developed, through which the eggshell thicknesses of Co and Mo could be easily regulated by controlling the impre...A simple method for preparation of presulfided eggshell CoMoS/γ-Al2O3 catalysts with sharp boundary is developed, through which the eggshell thicknesses of Co and Mo could be easily regulated by controlling the impregnation time. According to the results characterized by EDS, XRD, HRTEM and FT-IR of adsorbed CO, the active component structures, the nature and/or the amount of active sites on the eggshell catalyst are similar to these on the uniform catalyst. The evaluation results of the catalytic performance in selective hydrodesulfurization （HDS） of FCC gasoline show the presence of significant internal diffusion inhibition effect on HDS of S-compounds especially in the uniform catalyst. Compared with uniform catalyst, the eggshell catalyst could remarkably reduce such an internal diffusion inhibition effect due to a shortened diffusion path of the reactants, thus showing higher HDS activity and selectivity.展开更多
A series of B-Ni2P/SBA-15/cord monolithic catalysts were prepared by coating the slurry of the B-Ni2P/SBA-15 precursors on a pretreated cordierite support, and followed by temperature-programmed reduction in a H2 flow...A series of B-Ni2P/SBA-15/cord monolithic catalysts were prepared by coating the slurry of the B-Ni2P/SBA-15 precursors on a pretreated cordierite support, and followed by temperature-programmed reduction in a H2 flow. The samples were characterized by X-ray diffraction （XRD） and N2 adsorption-desorption technique. The catalytic activities for the hydrodesulfurization （HDS） of dibenzothiophene （DBT） were evaluated. The results showed that Ni2P phase was present in all B-Ni2P/SBA-1 5/cord monolithic catalysts. The specific surface areas （SBET） of the B-Ni2P/SBA-15/cord monolithic catalysts was first increased to 167 m2· g-1, and then decreased to 155 m2· g-1 with the increase of boron contents. The catalytic activity also showed the similar trend with the increase of boron contents. The 1.75% （by mass） B-Ni2P/SBA-15/cord monolithic catalysts exhibited the highest DBT conversion of 98.4% at 380 ℃. The cordierite-based monolithic catalysts showed better low temperature sensitivity for HDS of DBT in comparison with the particle catalysts. Moreover, two HDS routes, direct desulfurization （DDS） and hydrogenation （HYD）, proceeded independently over B-Ni2P/SBA-15/cord monolithic catalysts and the main pathway was DDS.展开更多
In the current study simultaneous reactions of hydrodesulfurization(HDS) of dibenzothiophene(DBT) and reforming of methanol in a micro-autoclave reactor were studied over bi-metallic(Co-Mo/Al2O3 and Ni-Mo/Al2O3) and t...In the current study simultaneous reactions of hydrodesulfurization(HDS) of dibenzothiophene(DBT) and reforming of methanol in a micro-autoclave reactor were studied over bi-metallic(Co-Mo/Al2O3 and Ni-Mo/Al2O3) and tri-metallic(Pd-Co-Mo/Al2O3 and Pd-Ni-Mo/Al2O3) catalyst systems which were prepared by incipient impregnation method.In situ hydrogen utilization and low Pd loadings were the major targets of this study.For comparison purpose,catalytic activity was separately determined for both the methanol reforming and HDS of DBT reactions as well.Ni based catalysts were confirmed with better activity than Co ones for both the reactions with Pd promoted ones ranking at the top i.e.Pd-Ni-Mo/Al2O3 > Ni-Mo/Al2O3 > Pd-Co-Mo/Al2O3 > Co-Mo/Al2O3 where Pd-Ni-Mo/Al2O3 showed 91% DBT conversion at 380 ℃ and 12 h reaction time.Some of the selected organic additives on catalytic activity were tested for their effect toward HDS reaction which was unique with close relation to their chemical nature.Reaction products were quantitatively and qualitatively analyzed via HPLC and GC-MS techniques respectively which helped in elucidating reaction mechanism.展开更多
TiOz nanotubes （TiO2-NTs） were synthesized by the hydrothermal method. Co and Mo active components were supported on a series of the as-prepared TiO2-NTs samples which were calcined at different temperatures. The ef...TiOz nanotubes （TiO2-NTs） were synthesized by the hydrothermal method. Co and Mo active components were supported on a series of the as-prepared TiO2-NTs samples which were calcined at different temperatures. The effects of support calcination temperature of CoMo/TiOz- NTs catalysts on their catalytic performance were investigated for selective hydrodesulfurization （HDS）. The samples were characterized by means of the scanning electron microscopy （SEM）, the transmission electron microscopy （TEM）, N2 adsorption-desorption, X-ray diffraction （XRD）, Raman spectroscopy and H2 temperature-programmed reduction （Hz-TPR）. The experimental results revealed that TiOz-NTs support calcined under 500℃ can maintain the nanotubular structure with higher surface area and pore volume. Meanwhile, the obtained supported CoMo/TiO2-NTs catalysts exhibited weak metal-support interaction, more octahedral Mo6＋ species and high catalytic performance in selective HDS.展开更多
Based on the study relating to the influence of additives on the hydrodesulfurization performance of Fe-Mo-Al2O3 catalysts, it was found out that the introduction of additives could increase considerably the activity ...Based on the study relating to the influence of additives on the hydrodesulfurization performance of Fe-Mo-Al2O3 catalysts, it was found out that the introduction of additives could increase considerably the activity of Fe-Mo/Al2O3 catalysts in the reaction of hydrodesulfurization of gasoline and diesel fractions. The introduction of zeolites (HY, HZSM) and other additives could lead to an increase of the concentration of acid centers, which were able to react with sulfur compounds, along with an increase of total catalysts’ pore volume, which could improve the capability of catalyst to adsorb the hydrogen and feed oil.展开更多
基金SINOPEC for its financial support(No.108012/No.108041)
文摘Six Ni-Mo catalysts with different metal contents were prepared and characterized by N2 adsorption and X-ray diffi＇actometry. The active phase microstructure of these catalysts was examined by the Raman spectroscopy, temperature- programmed reduction （TPR）, X-ray photoelectron spectroscopy, and high-resolution transmission electron microscopy. Hydrodesulfurization （HDS） activity of catalyst samples were analyzed in a flow fixed-bed microreactor. The sulfidation degree of Mo and the length of the MoS2 slab slightly increased with the amount of metal loaded following sulfidation. This small change is attributed to polymolybdate species observed in all the oxidized catalysts. Weak metal-support interactions, as determined by the TPR technique, increased the NiSx sulfidation phase and MoS2 slab stacking. The HDS activity of the catalyst samples increased with the number of active sites. For high metal loading catalysts, their HDS activity was nearly identical because the sulfur atoms cannot easily approach active sites. This change is caused by the large number of stacked layers in the MoS2 slabs as well as the decrease in the specific surface area and pore volume of the catalyst samples with an increasing metal loading.
文摘The influence of active metal components of catalyst, additives and catalyst preparation method on the reactivity of catalyst for selective hydrodesulfurization (HDS) of FCC naphtha was investigated, and the RSDS-21 catalyst with high HDS performance and the RSDS-22 catalyst with high selectivity were developed by RIPP. The composite loading of a new series of catalysts for selective HDS of FCC gasoline has demonstrated excellent desulfurization activity and selectivity and can under conventional hydrotreating conditions manufacture clean gasoline product meeting the national IV emission standard and the Euro V emission standard with less loss in antiknock index. The finalized new series of FCC catalysts upon being adopted for selective HDS of FCC naphtha have good adaptability to different feedstocks along with good stability.
基金supports by National Natural Science Foundation of China(NSFC)(Nos.21878329 and 21476257)the National Key Research and Development Program Nanotechnology Specific Project(No.2020YFA0210900)Science Foundation of China University of Petroleum,Beijing(No.2462018QZDX04).
文摘More stringent environmental legislation imposes severe requirements to reduce the sulfur content in diesel to ultra-low levels with high efficient catalysts.In this paper,a series of CoMo/NDC@alumina catalysts were synthesized by combination of the chemical vapor deposition of nitrogen-doped carbon(NDC)using 1,10-phenanthroline and co-impregnation of Mo and Co active components.The optimal catalyst with additive of 25%1,10-phenanthroline was screened by a series of property characterization and the hydrodesulfrization(HDS)active test.The amount of“CoMoS”active phase of the optimal CoMo/C3 catalyst increased 5.3%as compared with the CoMo/c-Al_(2)O_(3).The introduction of NDC improved the sulfidation degree of Mo by 21.8%as compared to the CoMo/c-Al_(2)O_(3) catalyst,which was beneficial to form more active sites.The HDS conversion of the NDC supported catalysts are higher than CoMo/c-Al_(2)O_(3) whether for the dibenzothiophene(DBT)or 4,6-dimethyl dibenzothiophene(4,6-DMDBT).Further hydroprocessing evaluation with Dagang diesel revealed that the CoMo/C3 catalyst possessed higher HDS property and the removal rate of DBTs in the diesel increased by 4%–11%as compared to the CoMo/c-Al_(2)O_(3) catalyst.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.21776048,21576290,21106182)the Natural Science Foundation of Fujian Province(2018J06002)。
文摘A series of NiMo/FDU-12 catalysts with tunable pore diameters and mesostructures have been controllably synthesized by adjusting the synthetic hydrothermal temperature and applied for the hydrodesulfurization of dibenzothiophene and its derivative.The state-of-the-art electron tomography revealed that the pore sizes of FDU-12 supports were enlarged with the increase in the hydrothermal temperature and the mesostructures were transformed from ordered cage-type pores to locally disordered channels.Meanwhile,the MoS2 morphology altered from small straight bar to semibending arc to spherical shape and finally to larger straight bar with the change of support structures.Among them,FDU-12 hydrothermally treated at 150℃possessed appropriate pore diameter and connected pore structure and was favorable for the formation of highly active MoS2 with curved morphology;thus,its corresponding catalyst exhibited the best HDS activity.Furthermore,it was indicated that the isomerization pathway could be significantly improved for HDS of 4,6-dimethyldibenzothiophene after the addition of aluminum,which was expected to be applied to the removal of the macromolecular sulfur compounds.Our study sheds lights on the relationship between support effect,active sites morphology and HDS performance,and also provides a guidance for the development of highly active HDS catalysts.
基金supported by grants from the Major State Basic Research Development Program of China ("973" Program, 2010CB226905)the National Natural Science Foundation of China (Grant Nos. 21006128 and 21106185)+2 种基金the Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20100133120007)the Shandong Provincial Natural Science Foundation of China (ZR2011BQ002)the Fundamental Research Funds for the Central Universities and the Graduate Innovation Project of China University of Petroleum (Grant No. CXZD11-06)
文摘A simple method for preparation of presulfided eggshell CoMoS/γ-Al2O3 catalysts with sharp boundary is developed, through which the eggshell thicknesses of Co and Mo could be easily regulated by controlling the impregnation time. According to the results characterized by EDS, XRD, HRTEM and FT-IR of adsorbed CO, the active component structures, the nature and/or the amount of active sites on the eggshell catalyst are similar to these on the uniform catalyst. The evaluation results of the catalytic performance in selective hydrodesulfurization （HDS） of FCC gasoline show the presence of significant internal diffusion inhibition effect on HDS of S-compounds especially in the uniform catalyst. Compared with uniform catalyst, the eggshell catalyst could remarkably reduce such an internal diffusion inhibition effect due to a shortened diffusion path of the reactants, thus showing higher HDS activity and selectivity.
基金Supported by the National Basic Research Program of China(2006CB202503)the Science Foundation of PetroChina(2010D-5006-0401)
文摘A series of B-Ni2P/SBA-15/cord monolithic catalysts were prepared by coating the slurry of the B-Ni2P/SBA-15 precursors on a pretreated cordierite support, and followed by temperature-programmed reduction in a H2 flow. The samples were characterized by X-ray diffraction （XRD） and N2 adsorption-desorption technique. The catalytic activities for the hydrodesulfurization （HDS） of dibenzothiophene （DBT） were evaluated. The results showed that Ni2P phase was present in all B-Ni2P/SBA-1 5/cord monolithic catalysts. The specific surface areas （SBET） of the B-Ni2P/SBA-15/cord monolithic catalysts was first increased to 167 m2· g-1, and then decreased to 155 m2· g-1 with the increase of boron contents. The catalytic activity also showed the similar trend with the increase of boron contents. The 1.75% （by mass） B-Ni2P/SBA-15/cord monolithic catalysts exhibited the highest DBT conversion of 98.4% at 380 ℃. The cordierite-based monolithic catalysts showed better low temperature sensitivity for HDS of DBT in comparison with the particle catalysts. Moreover, two HDS routes, direct desulfurization （DDS） and hydrogenation （HYD）, proceeded independently over B-Ni2P/SBA-15/cord monolithic catalysts and the main pathway was DDS.
基金Fundamental Research Foundation of Sinopec(X505015)
文摘In the current study simultaneous reactions of hydrodesulfurization(HDS) of dibenzothiophene(DBT) and reforming of methanol in a micro-autoclave reactor were studied over bi-metallic(Co-Mo/Al2O3 and Ni-Mo/Al2O3) and tri-metallic(Pd-Co-Mo/Al2O3 and Pd-Ni-Mo/Al2O3) catalyst systems which were prepared by incipient impregnation method.In situ hydrogen utilization and low Pd loadings were the major targets of this study.For comparison purpose,catalytic activity was separately determined for both the methanol reforming and HDS of DBT reactions as well.Ni based catalysts were confirmed with better activity than Co ones for both the reactions with Pd promoted ones ranking at the top i.e.Pd-Ni-Mo/Al2O3 > Ni-Mo/Al2O3 > Pd-Co-Mo/Al2O3 > Co-Mo/Al2O3 where Pd-Ni-Mo/Al2O3 showed 91% DBT conversion at 380 ℃ and 12 h reaction time.Some of the selected organic additives on catalytic activity were tested for their effect toward HDS reaction which was unique with close relation to their chemical nature.Reaction products were quantitatively and qualitatively analyzed via HPLC and GC-MS techniques respectively which helped in elucidating reaction mechanism.
文摘TiOz nanotubes （TiO2-NTs） were synthesized by the hydrothermal method. Co and Mo active components were supported on a series of the as-prepared TiO2-NTs samples which were calcined at different temperatures. The effects of support calcination temperature of CoMo/TiOz- NTs catalysts on their catalytic performance were investigated for selective hydrodesulfurization （HDS）. The samples were characterized by means of the scanning electron microscopy （SEM）, the transmission electron microscopy （TEM）, N2 adsorption-desorption, X-ray diffraction （XRD）, Raman spectroscopy and H2 temperature-programmed reduction （Hz-TPR）. The experimental results revealed that TiOz-NTs support calcined under 500℃ can maintain the nanotubular structure with higher surface area and pore volume. Meanwhile, the obtained supported CoMo/TiO2-NTs catalysts exhibited weak metal-support interaction, more octahedral Mo6＋ species and high catalytic performance in selective HDS.
文摘Based on the study relating to the influence of additives on the hydrodesulfurization performance of Fe-Mo-Al2O3 catalysts, it was found out that the introduction of additives could increase considerably the activity of Fe-Mo/Al2O3 catalysts in the reaction of hydrodesulfurization of gasoline and diesel fractions. The introduction of zeolites (HY, HZSM) and other additives could lead to an increase of the concentration of acid centers, which were able to react with sulfur compounds, along with an increase of total catalysts’ pore volume, which could improve the capability of catalyst to adsorb the hydrogen and feed oil.
