The growth and orientation of zeolite crystals on a glass substrate was investigated by changing the roughness and setting of the substrate surface.The orientation control of crystals on the glass substrate was achiev...The growth and orientation of zeolite crystals on a glass substrate was investigated by changing the roughness and setting of the substrate surface.The orientation control of crystals on the glass substrate was achieved.It was found that the setting and treatment of the glass substrate had a substantial effect on crystal orientation.When the substrate surface was upward, the preferential growth of crystal was along the a-axis.However, the preferential growth of crystal was along b-axis when the substrate surface was downward.According to experimental results, a film formation mechanism was proposed to account for the growth and orientation of crystals on the glass substrate.展开更多
Synthesis of high performance Silicalite-1 zeolite membranes on silica tubes was first reported in this paper.After two-step in-situ hydrothermal synthesis,well intergrown Silicalite-1 zeolite membranes were synthesiz...Synthesis of high performance Silicalite-1 zeolite membranes on silica tubes was first reported in this paper.After two-step in-situ hydrothermal synthesis,well intergrown Silicalite-1 zeolite membranes were synthesized on silica tubes after aging at 75 ℃ for 12 h.The Silicalite-1 zeolite membranes were characterized by SEM.The separation performance towards ethanol/water mixtures was evaluated by pervaporation.With temperature increasing,the flux of S-1 membrane,increased from 0.2 kg·m-2·h-1 at 30 ℃ to ca. 1.0 kg·m-2·h-1 at 80 ℃, while the separation factor decreased from 110 to 89.These results showed that silica supports may be more suitable for preparing high performance Silicalite-1 membranes.展开更多
研究了氢氟酸后处理对silicalite-1催化环己酮肟气相Beckmann重排反应性能的影响.结果表明,经适当浓度的氢氟酸溶液处理后,催化剂的选择性和稳定性都明显改善.其中,silicalite-1原粉先经硝酸铵预处理后再进行氢氟酸后处理所得到的催化...研究了氢氟酸后处理对silicalite-1催化环己酮肟气相Beckmann重排反应性能的影响.结果表明,经适当浓度的氢氟酸溶液处理后,催化剂的选择性和稳定性都明显改善.其中,silicalite-1原粉先经硝酸铵预处理后再进行氢氟酸后处理所得到的催化剂催化性能最好,反应53 h后环己酮肟的转化率仍保持在96%左右,己内酰胺的选择性高达96.1%.XRD,FT-IR和29Si MAS NMR的结果表明,较高的具有氢键相互作用的硅羟基与孤立硅羟基的比例值对环己酮肟气相Beckmann重排反应有利,同时,silicalite-1表面硅原子的排布方式对该反应也有重要影响.展开更多
文摘The growth and orientation of zeolite crystals on a glass substrate was investigated by changing the roughness and setting of the substrate surface.The orientation control of crystals on the glass substrate was achieved.It was found that the setting and treatment of the glass substrate had a substantial effect on crystal orientation.When the substrate surface was upward, the preferential growth of crystal was along the a-axis.However, the preferential growth of crystal was along b-axis when the substrate surface was downward.According to experimental results, a film formation mechanism was proposed to account for the growth and orientation of crystals on the glass substrate.
文摘Synthesis of high performance Silicalite-1 zeolite membranes on silica tubes was first reported in this paper.After two-step in-situ hydrothermal synthesis,well intergrown Silicalite-1 zeolite membranes were synthesized on silica tubes after aging at 75 ℃ for 12 h.The Silicalite-1 zeolite membranes were characterized by SEM.The separation performance towards ethanol/water mixtures was evaluated by pervaporation.With temperature increasing,the flux of S-1 membrane,increased from 0.2 kg·m-2·h-1 at 30 ℃ to ca. 1.0 kg·m-2·h-1 at 80 ℃, while the separation factor decreased from 110 to 89.These results showed that silica supports may be more suitable for preparing high performance Silicalite-1 membranes.
文摘研究了氢氟酸后处理对silicalite-1催化环己酮肟气相Beckmann重排反应性能的影响.结果表明,经适当浓度的氢氟酸溶液处理后,催化剂的选择性和稳定性都明显改善.其中,silicalite-1原粉先经硝酸铵预处理后再进行氢氟酸后处理所得到的催化剂催化性能最好,反应53 h后环己酮肟的转化率仍保持在96%左右,己内酰胺的选择性高达96.1%.XRD,FT-IR和29Si MAS NMR的结果表明,较高的具有氢键相互作用的硅羟基与孤立硅羟基的比例值对环己酮肟气相Beckmann重排反应有利,同时,silicalite-1表面硅原子的排布方式对该反应也有重要影响.
