采用直接水热合成和后合成两种方法制备Al-ITQ-13分子筛,用于催化甲醇转化制备烃类化合物。采用XRD、27Al M AS NM R、NH3-TPD、Py-FTIR和SEM等技术对所合成样品进行了表征。结果表明,两种方法制备的Al-ITQ-13结晶度都较高,且晶体形貌...采用直接水热合成和后合成两种方法制备Al-ITQ-13分子筛,用于催化甲醇转化制备烃类化合物。采用XRD、27Al M AS NM R、NH3-TPD、Py-FTIR和SEM等技术对所合成样品进行了表征。结果表明,两种方法制备的Al-ITQ-13结晶度都较高,且晶体形貌为薄片。与ZSM-5相比,Al-ITQ-13在甲醇转化反应中显示出较高的丙烯选择性、较高的丙烯/乙烯产物比以及较好的催化稳定性。同时,由于后合成所得到的Si Al(B)-ITQ-13强酸量减少,其催化性能优于直接合成的Si Ge Al-ITQ-13。展开更多
The optimum conditions for preparation of Al 13 sulfate were investigated.Some important parameters such as the ratio of n( OH - ) / n( Al ) ,reaction temperature,base injection rate,mixing intensity and ageing tim e ...The optimum conditions for preparation of Al 13 sulfate were investigated.Some important parameters such as the ratio of n( OH - ) / n( Al ) ,reaction temperature,base injection rate,mixing intensity and ageing tim e were identified.The hydroxyl ligand number and aging time are determinate fac tors for the forming of Al 13 .The nice tetrahedral sulfate was characterized by XRD and SEM,and the mol ecular formula was inferred to be[NaAlO 4 Al 12 (OH) 24 (H 2 O) 12 ](SO 4 ) 4 .This crystal was used as standard matter for preparation of polynuclear Al species(Al 13 ).The purity,stability and storage condition of the polynuclear Al 13 solution were explored.展开更多
The effects of conform continuous extrusion and subsequent heat treatment on the mechanical and wear-resistance properties of high-alloying Al–13Si–7.5Cu–1Mg alloy were investigated.The microstructures of alloys be...The effects of conform continuous extrusion and subsequent heat treatment on the mechanical and wear-resistance properties of high-alloying Al–13Si–7.5Cu–1Mg alloy were investigated.The microstructures of alloys before and after conform processing and aging were compared by transmission electron microscopy and scanning electron microscopy,respectively.The results reveal that the primary phases were broken and refined by intense shear deformation during conform processing.After the conform-prepared Al–13Si–7.5Cu–1Mg alloy was subjected to solid-solution treatment at 494℃for 1.5 h and aging at 180℃for 4 h,its hardness improved from HBS 115.8 to HBS 152.5 and its ultimate tensile strength increased from 112.6 to 486.8 MPa.Its wear resistance was also enhanced.The factors leading to the enhanced strength,hardness,and wear resistance of the alloy were discussed in detail.展开更多
基金supported by Doctoral Scientific Research Foundation of Shanxi Datong University (2015-B-02)
文摘采用直接水热合成和后合成两种方法制备Al-ITQ-13分子筛,用于催化甲醇转化制备烃类化合物。采用XRD、27Al M AS NM R、NH3-TPD、Py-FTIR和SEM等技术对所合成样品进行了表征。结果表明,两种方法制备的Al-ITQ-13结晶度都较高,且晶体形貌为薄片。与ZSM-5相比,Al-ITQ-13在甲醇转化反应中显示出较高的丙烯选择性、较高的丙烯/乙烯产物比以及较好的催化稳定性。同时,由于后合成所得到的Si Al(B)-ITQ-13强酸量减少,其催化性能优于直接合成的Si Ge Al-ITQ-13。
文摘The optimum conditions for preparation of Al 13 sulfate were investigated.Some important parameters such as the ratio of n( OH - ) / n( Al ) ,reaction temperature,base injection rate,mixing intensity and ageing tim e were identified.The hydroxyl ligand number and aging time are determinate fac tors for the forming of Al 13 .The nice tetrahedral sulfate was characterized by XRD and SEM,and the mol ecular formula was inferred to be[NaAlO 4 Al 12 (OH) 24 (H 2 O) 12 ](SO 4 ) 4 .This crystal was used as standard matter for preparation of polynuclear Al species(Al 13 ).The purity,stability and storage condition of the polynuclear Al 13 solution were explored.
基金financially supported by the National Natural Science Foundation of China (No.51274245)
文摘The effects of conform continuous extrusion and subsequent heat treatment on the mechanical and wear-resistance properties of high-alloying Al–13Si–7.5Cu–1Mg alloy were investigated.The microstructures of alloys before and after conform processing and aging were compared by transmission electron microscopy and scanning electron microscopy,respectively.The results reveal that the primary phases were broken and refined by intense shear deformation during conform processing.After the conform-prepared Al–13Si–7.5Cu–1Mg alloy was subjected to solid-solution treatment at 494℃for 1.5 h and aging at 180℃for 4 h,its hardness improved from HBS 115.8 to HBS 152.5 and its ultimate tensile strength increased from 112.6 to 486.8 MPa.Its wear resistance was also enhanced.The factors leading to the enhanced strength,hardness,and wear resistance of the alloy were discussed in detail.
