The production of heavy and extra-heavy oil is challenging because of the rheological properties that crude oil presents due to its high asphaltene content.The upgrading and recovery processes of these unconventional ...The production of heavy and extra-heavy oil is challenging because of the rheological properties that crude oil presents due to its high asphaltene content.The upgrading and recovery processes of these unconventional oils are typically water and energy intensive,which makes such processes costly and environmentally unfriendly.Nanoparticle catalysts could be used to enhance the upgrading and recovery of heavy oil under both in situ and ex situ conditions.In this study,the effect of the Ni-Pd nanocatalysts supported on fumed silica nanoparticles on post-adsorption catalytic thermal cracking of n-C_7 asphaltenes was investigated using a thermogravimetric analyzer coupled with FTIR.The performance of catalytic thermal cracking of n-C_7asphaltenes in the presence of NiO and PdO supported on fumed silica nanoparticles was better than on the fumed silica support alone.For a fixed amount of adsorbed n-C_7asphaltenes（0.2 mg/m～2）,bimetallic nanoparticles showed better catalytic behavior than monometallic nanoparticles,confirming their synergistic effects.The corrected OzawaFlynn-Wall equation（OFW） was used to estimate the effective activation energies of the catalytic process.The mechanism function,kinetic parameters,and transition state thermodynamic functions for the thermal cracking process of n-C_7 asphaltenes in the presence and absence of nanoparticles are investigated.展开更多
The crystal and molecular structure of the complex containing cobalt-carbon and iron- sulfur cluster cores,(μ-ρ-CH_3C_6H_4C_2S)(μ-n-C_3H_7S)Fe_2(CO)_6Co_2(CO)_6,has been determined by X-ray diffraction method.The c...The crystal and molecular structure of the complex containing cobalt-carbon and iron- sulfur cluster cores,(μ-ρ-CH_3C_6H_4C_2S)(μ-n-C_3H_7S)Fe_2(CO)_6Co_2(CO)_6,has been determined by X-ray diffraction method.The crystals are triclinic,space group P,with a=9.139(2),b=9.610(1), c=17.183(2),α=84.36(1),β=89.45(1),γ=88.15(1)°,V=1501.0~3;Z=2,D_c=1.74 g/cm^3. R=0.072,Rw=0.081.The results of the structure determination show a cobalt-carbon cluster core formed through the reaction of(μ-ρ-CH_3C_6H_4C_2S)(μ-n-C_3H_7S)Fe_2(CO)_6 with Co_2(CO)_8.In the cobalt-carbon cluster core,the bond length of the original C≡C lengthened to 1.324 which is close to the typical value of carbon-carbon double bond.The groups connecting the carbons of the cluster core are in cis position and lie on the opposite side of cobalt atoms.In this complex,the conformation of-SC_3H_7 is e-type,while that of-SC_2C_6H_4CH_3 is a-type.展开更多
基金supported by the National Natural Science Foundation of China(20973194)Project of Science & Technology from Chongqing Municipal Education Commission,China(KJ090626)Research Foundation of Chongqing University of Technology,China(2008ZD18)~~
基金the Natural Sciences and Engineering Research Council of Canada (NSERC)the Department of Chemical and Petroleum Engineering at the Schulich School of Engineering at the University of Calgary
文摘The production of heavy and extra-heavy oil is challenging because of the rheological properties that crude oil presents due to its high asphaltene content.The upgrading and recovery processes of these unconventional oils are typically water and energy intensive,which makes such processes costly and environmentally unfriendly.Nanoparticle catalysts could be used to enhance the upgrading and recovery of heavy oil under both in situ and ex situ conditions.In this study,the effect of the Ni-Pd nanocatalysts supported on fumed silica nanoparticles on post-adsorption catalytic thermal cracking of n-C_7 asphaltenes was investigated using a thermogravimetric analyzer coupled with FTIR.The performance of catalytic thermal cracking of n-C_7asphaltenes in the presence of NiO and PdO supported on fumed silica nanoparticles was better than on the fumed silica support alone.For a fixed amount of adsorbed n-C_7asphaltenes（0.2 mg/m～2）,bimetallic nanoparticles showed better catalytic behavior than monometallic nanoparticles,confirming their synergistic effects.The corrected OzawaFlynn-Wall equation（OFW） was used to estimate the effective activation energies of the catalytic process.The mechanism function,kinetic parameters,and transition state thermodynamic functions for the thermal cracking process of n-C_7 asphaltenes in the presence and absence of nanoparticles are investigated.
文摘The crystal and molecular structure of the complex containing cobalt-carbon and iron- sulfur cluster cores,(μ-ρ-CH_3C_6H_4C_2S)(μ-n-C_3H_7S)Fe_2(CO)_6Co_2(CO)_6,has been determined by X-ray diffraction method.The crystals are triclinic,space group P,with a=9.139(2),b=9.610(1), c=17.183(2),α=84.36(1),β=89.45(1),γ=88.15(1)°,V=1501.0~3;Z=2,D_c=1.74 g/cm^3. R=0.072,Rw=0.081.The results of the structure determination show a cobalt-carbon cluster core formed through the reaction of(μ-ρ-CH_3C_6H_4C_2S)(μ-n-C_3H_7S)Fe_2(CO)_6 with Co_2(CO)_8.In the cobalt-carbon cluster core,the bond length of the original C≡C lengthened to 1.324 which is close to the typical value of carbon-carbon double bond.The groups connecting the carbons of the cluster core are in cis position and lie on the opposite side of cobalt atoms.In this complex,the conformation of-SC_3H_7 is e-type,while that of-SC_2C_6H_4CH_3 is a-type.
