NaA zeolite membranes with 80 cm in length and 12.8 mm in outer diameter were prepared by our research group cooperating with Nanjing Jiusi Hi-Tech Co., China. The influence of dissolved inorganic salts and pH value i...NaA zeolite membranes with 80 cm in length and 12.8 mm in outer diameter were prepared by our research group cooperating with Nanjing Jiusi Hi-Tech Co., China. The influence of dissolved inorganic salts and pH value in the feed of isopropanol （IPA） solution on NaA zeolite membranes was investigated. It was found that both factors exhibited strong influence on the stability of NaA zeolite membranes. A set of pretreatment steps such as pH adjustment and distillation of the IPA solution were proposed to improve stability for pervaporation dehydration. An industrial-scale pervaporation facility with 52 m2 membrane area was built to dehydrate IPA solution from industrial cephalosporin production. The facility was continuously operated at 368-378 K to dehydrate IPA solution from water mass content of 15%-20% to less than 2% with a feed flow rate of 400-500 L·h^-1 and an average water flux of 1-1.5 kg·m^-2·h-1. The successful application of this facility suggested a promising application of NaA zeolite mem-brane for IPA recovery from pharmaceutical production.展开更多
Silver modified HZSM-5 （AgHZ） zeolite catalysts were prepared by ion exchange method and their catalytic properties in the l-butene cracking reaction were measured. The catalysts were characterized by infrared spec-...Silver modified HZSM-5 （AgHZ） zeolite catalysts were prepared by ion exchange method and their catalytic properties in the l-butene cracking reaction were measured. The catalysts were characterized by infrared spec- troscopy with pyridine adsorption （Py-IR）, N2 adsorption and X-ray diffraction （XRD）. The effects of Ag loading and steaming treatment on catalytic performances were studied. It is found that the activity ofHT_SM-5 （HZ） catalyst significantly decreases with the steaming time, whereas AgHZ catalysts show stable activity in the steaming time of 24-48 h and their activities increase with the Ag loading. When the steaming time is 24-48 h, the yield of propylene over HZ catalyst significantly decreases, whereas it is stable over AgHZ catalysts. The AgHZ catalysts with Ag loadings of 0.28%-0.43% （by mass） show similar propylene yields （-30%）, which are higher than that over the AgHZ catalyst with a Ag loading of 0.55% （by mass）. These results indicate that the steam-treated AgHZ catalysts with optimum Ag loadings have higher yield of propylene and are more stable than the steam- treated HZ catalyst. The regeneration stability measurement in butene cracking also shows that the AgHZ catalyst steam-treated under a suitable condition has better stability than the HZ catalyst.展开更多
The synthesis of mesoporous material SBA-15 has been extensively reported in the past decades, which possesses a pore diameter of 6-8 nm on average. Here, a simple post-synthesis procedure has been developed to synthe...The synthesis of mesoporous material SBA-15 has been extensively reported in the past decades, which possesses a pore diameter of 6-8 nm on average. Here, a simple post-synthesis procedure has been developed to synthesize SBA-15 with further expanded pore diameter to above 10 nm simply by a solvothermal treatment replacing traditional hydrothermal step for mesopore template removal, which results in efficient pore expansion and the significantly promoted condensation of silica framework as well. This facile approach is believed applicable for pore expansions of other kinds of mesoporous silica materials.展开更多
基金Supported by the National t）asic Research Program of China （2009CB623403）, the National High Technology Research and De velopment Program of China （2009AA034802）, the National Natural Science Foundation of China （20706030, U0834004）, the Science ＆ Technology Support Program （Industry） of Jiangsu Province of China （BE2008141）, the Natural Science Foundation of the Jiangsu Higher Education Institutions （09KJA530002） and 333 High-Level Personnel Training Project in Jiangsu Province. ＊＊ To whom correspondence should be addressed. E-mail： Xuehonggu@yahoo.com
文摘NaA zeolite membranes with 80 cm in length and 12.8 mm in outer diameter were prepared by our research group cooperating with Nanjing Jiusi Hi-Tech Co., China. The influence of dissolved inorganic salts and pH value in the feed of isopropanol （IPA） solution on NaA zeolite membranes was investigated. It was found that both factors exhibited strong influence on the stability of NaA zeolite membranes. A set of pretreatment steps such as pH adjustment and distillation of the IPA solution were proposed to improve stability for pervaporation dehydration. An industrial-scale pervaporation facility with 52 m2 membrane area was built to dehydrate IPA solution from industrial cephalosporin production. The facility was continuously operated at 368-378 K to dehydrate IPA solution from water mass content of 15%-20% to less than 2% with a feed flow rate of 400-500 L·h^-1 and an average water flux of 1-1.5 kg·m^-2·h-1. The successful application of this facility suggested a promising application of NaA zeolite mem-brane for IPA recovery from pharmaceutical production.
基金Supported by the National Science Foundation of China(U1162129)the Science and Technology Department of Zhejiang Province(2009R50020)
文摘Silver modified HZSM-5 （AgHZ） zeolite catalysts were prepared by ion exchange method and their catalytic properties in the l-butene cracking reaction were measured. The catalysts were characterized by infrared spec- troscopy with pyridine adsorption （Py-IR）, N2 adsorption and X-ray diffraction （XRD）. The effects of Ag loading and steaming treatment on catalytic performances were studied. It is found that the activity ofHT_SM-5 （HZ） catalyst significantly decreases with the steaming time, whereas AgHZ catalysts show stable activity in the steaming time of 24-48 h and their activities increase with the Ag loading. When the steaming time is 24-48 h, the yield of propylene over HZ catalyst significantly decreases, whereas it is stable over AgHZ catalysts. The AgHZ catalysts with Ag loadings of 0.28%-0.43% （by mass） show similar propylene yields （-30%）, which are higher than that over the AgHZ catalyst with a Ag loading of 0.55% （by mass）. These results indicate that the steam-treated AgHZ catalysts with optimum Ag loadings have higher yield of propylene and are more stable than the steam- treated HZ catalyst. The regeneration stability measurement in butene cracking also shows that the AgHZ catalyst steam-treated under a suitable condition has better stability than the HZ catalyst.
基金supported by the National Basic Research Program of China(2012CB933602)the National Natural Science Foundation of China(51172070,51132009,51202068 and51472085)+1 种基金Shu Guang Project(11SG30)the Fundamental Research Funds for the Central Universities
文摘The synthesis of mesoporous material SBA-15 has been extensively reported in the past decades, which possesses a pore diameter of 6-8 nm on average. Here, a simple post-synthesis procedure has been developed to synthesize SBA-15 with further expanded pore diameter to above 10 nm simply by a solvothermal treatment replacing traditional hydrothermal step for mesopore template removal, which results in efficient pore expansion and the significantly promoted condensation of silica framework as well. This facile approach is believed applicable for pore expansions of other kinds of mesoporous silica materials.
