Layered double hydrotalcites pillared by het erop olyoxometates, ZnAl- GeW11Z (Z=Ni2+, Cu2+) and ZnAl-GeW11 have been synhesized by ion exchange. A procedure for intercalating layered double hydroxides is described in...Layered double hydrotalcites pillared by het erop olyoxometates, ZnAl- GeW11Z (Z=Ni2+, Cu2+) and ZnAl-GeW11 have been synhesized by ion exchange. A procedure for intercalating layered double hydroxides is described in this paper, powder X-ray diffraction and IR spectra measuremnts confirm that for GeW11O39Z (H2O)6- and GeW11O8-39intercalation takes place and the gallery heights are of 9.9A. The new compounds are found to be calalytically efficient for the esterification of acetic acid with n-butanol in liquld-phase.展开更多
Ainonic clays pillared by heteropolyoxometalate Zn2Al-PW11Z (Z= Cr3+ , Ti4+ and V5+) were synthesized via ion exchange reaction. The IR spectra and XRD patterns showed that the layered anions remained the integrity of...Ainonic clays pillared by heteropolyoxometalate Zn2Al-PW11Z (Z= Cr3+ , Ti4+ and V5+) were synthesized via ion exchange reaction. The IR spectra and XRD patterns showed that the layered anions remained the integrity of Keggin structure, and the gallery heights of the layered compounds were 1.01± 0.01 nm. The MAS NMR spectra of 27Al and 31P indicated the layered ahion had little effect on the Al of the octahedra center of the hydroalde, but the layer and octallydron VO6 had great effect on the P of the layered PW11V. The peak of 31P MAS NMR split to the two peaks of -11.867 ppm and -14.031 ppm whose corresponding area ratio is 2:1. All these results showed that the C2 axia of the heteropolyoxometalate in the layer was perpondicular to the brucite layer. Further experiments found that these compounds had high selectivity and activity for the esterification of acetic acid with n-butyl alcohol.展开更多
文摘Layered double hydrotalcites pillared by het erop olyoxometates, ZnAl- GeW11Z (Z=Ni2+, Cu2+) and ZnAl-GeW11 have been synhesized by ion exchange. A procedure for intercalating layered double hydroxides is described in this paper, powder X-ray diffraction and IR spectra measuremnts confirm that for GeW11O39Z (H2O)6- and GeW11O8-39intercalation takes place and the gallery heights are of 9.9A. The new compounds are found to be calalytically efficient for the esterification of acetic acid with n-butanol in liquld-phase.
文摘Ainonic clays pillared by heteropolyoxometalate Zn2Al-PW11Z (Z= Cr3+ , Ti4+ and V5+) were synthesized via ion exchange reaction. The IR spectra and XRD patterns showed that the layered anions remained the integrity of Keggin structure, and the gallery heights of the layered compounds were 1.01± 0.01 nm. The MAS NMR spectra of 27Al and 31P indicated the layered ahion had little effect on the Al of the octahedra center of the hydroalde, but the layer and octallydron VO6 had great effect on the P of the layered PW11V. The peak of 31P MAS NMR split to the two peaks of -11.867 ppm and -14.031 ppm whose corresponding area ratio is 2:1. All these results showed that the C2 axia of the heteropolyoxometalate in the layer was perpondicular to the brucite layer. Further experiments found that these compounds had high selectivity and activity for the esterification of acetic acid with n-butyl alcohol.
