The characteristics of magnetically stabilized bed(MSB)were studied in a three-phase system with nitrogen,water and iron powder(and/or Ni-RE-P amorphous alloy catalyst)as gas,liquid and solid phase respectively.The op...The characteristics of magnetically stabilized bed(MSB)were studied in a three-phase system with nitrogen,water and iron powder(and/or Ni-RE-P amorphous alloy catalyst)as gas,liquid and solid phase respectively.The operating state was observed,and the effect of magnetic field and superficial velocity of gas on minimum fluidization velocity were examined.Finally,the MSB using mixture of iron powder and Ni-RE-P amorphous alloy catalyst as solid phase was studied.展开更多
采用水热合成法制备了I M-5和TNU-9分子筛,并采用水蒸气处理法对其进行了改性。采用XRD、BET、TEM、吡啶-IR、29Si、27Al MAS NMR等手段对分子筛的物化性能进行了表征,并考察了分子筛在甲苯甲醇烷基化反应中的催化性能。结果表明,与ZSM-...采用水热合成法制备了I M-5和TNU-9分子筛,并采用水蒸气处理法对其进行了改性。采用XRD、BET、TEM、吡啶-IR、29Si、27Al MAS NMR等手段对分子筛的物化性能进行了表征,并考察了分子筛在甲苯甲醇烷基化反应中的催化性能。结果表明,与ZSM-5分子筛相比,I M-5和TNU-9分子筛在甲苯甲醇烷基化反应中具有较高的催化活性,二甲苯选择性高。经水蒸气处理后,ST-H-I M-5和ST-H-TNU-9分子筛的活性有所下降,ST-H-I M-5分子筛的二甲苯选择性高,ST-H-TNU-9分子筛的对二甲苯选择性达到40%左右。展开更多
Amorphous Ni B/SiO2 catalysts were prepared by chemical reduction of Ni2＋with KBH4.ICP was used to analyze the composition of alloys.XRD,TEM,SAED and HREM were used to examine the structures of samples fresh and afte...Amorphous Ni B/SiO2 catalysts were prepared by chemical reduction of Ni2＋with KBH4.ICP was used to analyze the composition of alloys.XRD,TEM,SAED and HREM were used to examine the structures of samples fresh and after thermal treatment in different atmospheres.The results indicated that the supported NiB has a higher structural stability than ultrafine NiB amorphous alloy.Low temperature pretreatment in hydrogen can reduce nickel oxide on the surface of catalysts.However,treatment in hydrogen is more favorable than in atmosphere and nitrogen for keeping it in stable state.展开更多
The hydrodynamic characteristics of liquid-fluidized magnetically stabilized beds (MSB) with commercial amorphous nickel alloy catalyst (SRNA-4) as solid phase and water as liquid phase in a cold model experimental ap...The hydrodynamic characteristics of liquid-fluidized magnetically stabilized beds (MSB) with commercial amorphous nickel alloy catalyst (SRNA-4) as solid phase and water as liquid phase in a cold model experimental apparatus of Φ140mm were investigated. The influence of magnetic field intensity on bed structure, pressure drop, minimum fluidization velocity, transition velocity, and liquid holdup were investigated. Mathematical models for minimum fluidization velocity, transition velocity, liquid holdup were established respectively. The operating phase diagrams of liquid-fluidized MSB with SRNA-4 catalyst of two different sizes were obtained.展开更多
文摘The characteristics of magnetically stabilized bed(MSB)were studied in a three-phase system with nitrogen,water and iron powder(and/or Ni-RE-P amorphous alloy catalyst)as gas,liquid and solid phase respectively.The operating state was observed,and the effect of magnetic field and superficial velocity of gas on minimum fluidization velocity were examined.Finally,the MSB using mixture of iron powder and Ni-RE-P amorphous alloy catalyst as solid phase was studied.
文摘Amorphous Ni B/SiO2 catalysts were prepared by chemical reduction of Ni2＋with KBH4.ICP was used to analyze the composition of alloys.XRD,TEM,SAED and HREM were used to examine the structures of samples fresh and after thermal treatment in different atmospheres.The results indicated that the supported NiB has a higher structural stability than ultrafine NiB amorphous alloy.Low temperature pretreatment in hydrogen can reduce nickel oxide on the surface of catalysts.However,treatment in hydrogen is more favorable than in atmosphere and nitrogen for keeping it in stable state.
文摘The hydrodynamic characteristics of liquid-fluidized magnetically stabilized beds (MSB) with commercial amorphous nickel alloy catalyst (SRNA-4) as solid phase and water as liquid phase in a cold model experimental apparatus of Φ140mm were investigated. The influence of magnetic field intensity on bed structure, pressure drop, minimum fluidization velocity, transition velocity, and liquid holdup were investigated. Mathematical models for minimum fluidization velocity, transition velocity, liquid holdup were established respectively. The operating phase diagrams of liquid-fluidized MSB with SRNA-4 catalyst of two different sizes were obtained.
