XRD and FT-IR methods were applied to the studies of organic monolayer dispersionsystems. Naphthalene, borneol, benzoic acid, salicylic acid, phthalic acid and tartaric acid weremixed with γ-Al2O3 and SiO2 separately...XRD and FT-IR methods were applied to the studies of organic monolayer dispersionsystems. Naphthalene, borneol, benzoic acid, salicylic acid, phthalic acid and tartaric acid weremixed with γ-Al2O3 and SiO2 separately. The results showed that the organic compounds canalso disperse spontaneously onto the surfaces of different oxide-supports to become high dispersionstates like the behavior of inorganic salts and oxides. The organic substances studied are moreready to disperse with 1ess carboxyl or hydroxyl groups on their aromatic nucleus, suggesting themigration on the surface of the support is rate-determining during the dispersion. This point ofview is supported by the result of IR spectroscopy. The IR spectra of dispersed systems suggestthat the carboxy1 may react with the surface hydroxyl groups of the support to form salt-likestructures on the surface.展开更多
In this paper,the systems of KCl/HZSM 5 and NaCl/HZSM 5 have been studied by XRD.The results show that the salts can disperse on the HZSM 5 surface forming a non crystalline layer.There is a critical dispersion capaci...In this paper,the systems of KCl/HZSM 5 and NaCl/HZSM 5 have been studied by XRD.The results show that the salts can disperse on the HZSM 5 surface forming a non crystalline layer.There is a critical dispersion capacity.When the salt content exceeds this threshold,the residual crystalline salt appears.Furthermore,the relationship between dispersion thresholds and calcination temperature has been investigated,the critical dispersion temperature of KCl and NaCl on the HZSM 5 surface has been found,and the dispersion threshold of salts from 450℃ to 700℃ has been measured.展开更多
文摘XRD and FT-IR methods were applied to the studies of organic monolayer dispersionsystems. Naphthalene, borneol, benzoic acid, salicylic acid, phthalic acid and tartaric acid weremixed with γ-Al2O3 and SiO2 separately. The results showed that the organic compounds canalso disperse spontaneously onto the surfaces of different oxide-supports to become high dispersionstates like the behavior of inorganic salts and oxides. The organic substances studied are moreready to disperse with 1ess carboxyl or hydroxyl groups on their aromatic nucleus, suggesting themigration on the surface of the support is rate-determining during the dispersion. This point ofview is supported by the result of IR spectroscopy. The IR spectra of dispersed systems suggestthat the carboxy1 may react with the surface hydroxyl groups of the support to form salt-likestructures on the surface.
文摘In this paper,the systems of KCl/HZSM 5 and NaCl/HZSM 5 have been studied by XRD.The results show that the salts can disperse on the HZSM 5 surface forming a non crystalline layer.There is a critical dispersion capacity.When the salt content exceeds this threshold,the residual crystalline salt appears.Furthermore,the relationship between dispersion thresholds and calcination temperature has been investigated,the critical dispersion temperature of KCl and NaCl on the HZSM 5 surface has been found,and the dispersion threshold of salts from 450℃ to 700℃ has been measured.
