Effects of vanadium on light olefins selectivity of FCC catalysts were investigated with vanadium having different oxidation numbers （hereinafter abbreviated as Oxnum）. Molecular modeling studies showed that vanadiu...Effects of vanadium on light olefins selectivity of FCC catalysts were investigated with vanadium having different oxidation numbers （hereinafter abbreviated as Oxnum）. Molecular modeling studies showed that vanadium with low Oxnum could affect the chemical conversion of large-size hydrocarbon molecules. However, the vanadium deposited on equilibrium catalyst bad high Oxnum because of the oxidation reaction taking place in the regenerator, so an activation method to reduce vanadium Oxnum named ＂selective activation＂ was introduced. It was proved by means of Electron Paramagnetic Resonance （EPR） and Temperature-Programmed Reduction （TPR） methods that the vanadium Oxnum was decreased, when the catalyst was activated. The molecular modeling studies are consistent well with the lab evaluation results. The light olefins selectivity of activated equilibrium catalysts was better than that achieved by the inactivated catalysts. Similar results were observed with the lab vanadium-contaminated catalyst. The light olefins selectivity of the catalyst was optimized when the vanadium Oxnum was close to 2 （VO）.展开更多
The thiophene removal ability of the synthesized NiZnO-based adsorbent was tested in a lab-scale fixed-bed system. The X-ray diffractometer (XRD) and the temperature-programmed reduction (H2-TPR) instrument were used ...The thiophene removal ability of the synthesized NiZnO-based adsorbent was tested in a lab-scale fixed-bed system. The X-ray diffractometer (XRD) and the temperature-programmed reduction (H2-TPR) instrument were used to characterize the samples. The XRD and TPR results showed that there existed stronger synergetic effect between ZnO and NiO to form well-dispersed adsorbent particles when the Zn/Ni molar ratio in adsorbent was 0.4, and that the optimum temperature for reduction of the NiZnO-based adsorbent was approximately in the range of 350℃—400℃. In addition, the effects of reaction temperature, and reaction pressure on the reactive adsorption desulfurization tests were studied.展开更多
Underground coal gasification （UCG） is one of the clean technologies to collect heat energy and gases （hydrogen, methane, etc.） in an underground coal seam. It is necessary to further developing environ- mentally ...Underground coal gasification （UCG） is one of the clean technologies to collect heat energy and gases （hydrogen, methane, etc.） in an underground coal seam. It is necessary to further developing environ- mentally friendly UCG system construction. One of the most important UCG＇s problems is underground control of combustion area for efficient gas production, estimation of subsidence and gas leakage to the surface. For this objective, laboratory experiments were conducted according to the UCG model to iden- ti[y the process of combustion cavity development by monitoring the electrical resistivity activity on the coal samples to setup fundamental data for the technology engineering to evaluate combustion area. While burning coal specimens, that had been sampled from various coal deposits, electrical resistivity was monitored. Symmetric four electrodes system （ABMN） of direct and low-frequency current electric resistance method was used for laboratory resistivity measurement of rock samples. Made research and the results suggest that front-end of electro conductivity activity during heating and combusting of coal specimen depended on heating temperature. Combusting coal electro conductivity has compli- cated multistage type of change. Electrical resistivity method is expected to be a useful geophysical tool to for evaluation of combustion volume and its migration in the coal seam.展开更多
文摘Effects of vanadium on light olefins selectivity of FCC catalysts were investigated with vanadium having different oxidation numbers （hereinafter abbreviated as Oxnum）. Molecular modeling studies showed that vanadium with low Oxnum could affect the chemical conversion of large-size hydrocarbon molecules. However, the vanadium deposited on equilibrium catalyst bad high Oxnum because of the oxidation reaction taking place in the regenerator, so an activation method to reduce vanadium Oxnum named ＂selective activation＂ was introduced. It was proved by means of Electron Paramagnetic Resonance （EPR） and Temperature-Programmed Reduction （TPR） methods that the vanadium Oxnum was decreased, when the catalyst was activated. The molecular modeling studies are consistent well with the lab evaluation results. The light olefins selectivity of activated equilibrium catalysts was better than that achieved by the inactivated catalysts. Similar results were observed with the lab vanadium-contaminated catalyst. The light olefins selectivity of the catalyst was optimized when the vanadium Oxnum was close to 2 （VO）.
文摘The thiophene removal ability of the synthesized NiZnO-based adsorbent was tested in a lab-scale fixed-bed system. The X-ray diffractometer (XRD) and the temperature-programmed reduction (H2-TPR) instrument were used to characterize the samples. The XRD and TPR results showed that there existed stronger synergetic effect between ZnO and NiO to form well-dispersed adsorbent particles when the Zn/Ni molar ratio in adsorbent was 0.4, and that the optimum temperature for reduction of the NiZnO-based adsorbent was approximately in the range of 350℃—400℃. In addition, the effects of reaction temperature, and reaction pressure on the reactive adsorption desulfurization tests were studied.
基金provided by the Ministry of EducationScience of Russian Federation (No. P1679),Far Eastern Federal University
文摘Underground coal gasification （UCG） is one of the clean technologies to collect heat energy and gases （hydrogen, methane, etc.） in an underground coal seam. It is necessary to further developing environ- mentally friendly UCG system construction. One of the most important UCG＇s problems is underground control of combustion area for efficient gas production, estimation of subsidence and gas leakage to the surface. For this objective, laboratory experiments were conducted according to the UCG model to iden- ti[y the process of combustion cavity development by monitoring the electrical resistivity activity on the coal samples to setup fundamental data for the technology engineering to evaluate combustion area. While burning coal specimens, that had been sampled from various coal deposits, electrical resistivity was monitored. Symmetric four electrodes system （ABMN） of direct and low-frequency current electric resistance method was used for laboratory resistivity measurement of rock samples. Made research and the results suggest that front-end of electro conductivity activity during heating and combusting of coal specimen depended on heating temperature. Combusting coal electro conductivity has compli- cated multistage type of change. Electrical resistivity method is expected to be a useful geophysical tool to for evaluation of combustion volume and its migration in the coal seam.
