A coordinative saturated vanadium containing metal organic framework that shows a remarkable catalytic activity

A completely saturated Metal Organic Framework, MIL-47 was synthesized and tested for its catalytic performance in the oxidation of cyclohexene with tert-butyl hydroperoxide as oxidant. The catalyst was compared to several reference catalysts: namely VAPO-5, supported VOx/SiO2 and the homogeneous catalyst VO(acac)(2). MIL-47 shows a remarkable catalytic activity and preserves its crystalline structure and surface area after a catalytic run. Furthermore MIL-47 exhibits a very high activity in successive runs

VAPO as catalyst for liquid phase oxidation reactions

Abstract The preparation, characterisation and catalytic properties of vanadium containing aluminophosphate molecular sieves (type AEL and AbT) are described in this paper. The molecular sieves were prepared by post-synthesis treatment and hydrothermal procedures. Several parameters were varied: nature of the template, crystallisation procedure and vanadium content. Tri-propylamine appeared to be the best template for the preparation of VAPO-5: highly crystalline, homogeneous batches (crystallite size: 2x I x 1 ~tm) with a maximum of about 2 wt% vanadium could be obtained in high yield (75-80%). Crystallographically pure VAPO-11 with a maximum of only 0.5 wt% of vanadium could be prepared. In VAPO the incorporation mode of vanadium gradually changes from tetra-to penta-coordinated when the amount of vanadium is increased. However the formation of vanadium pentoxide could not be detected. The vanadium containing molecular sieves were used as catalyst for the oxidation of allylic and secondary alcohols by tert-butyl hydroperoxide in the liquid phase. Compared with a homogeneous catalyst, bis(2,4-pentandionato)-oxovanadium(IV) (VO(acac)2), the activity of vanadium containing molecular sieves is a factor 3-100 times lower. The activity of VAPO becomes higher when the vanadium content is increased. The decomposition rate of the peroxide is influenced by the pore structure, whereas no other effects on the selectivity are found

Application of VAPO as catalyst for liquid phase oxidation reactions

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Application of VAPO-5 in liquid phase oxidation reactions: Indications for the presence of different vanadiumsites

VAPO-5's with different vanadium content (0.18 – 2.0 at%) have been used as catalyst for the liquid phase epoxidation of cinnamylalcohol (3-phenyl-2-propan-1-ol) by t-butylhydroperoxide (TBHP). It has been found that the activity, expressed as turn-over frequency (TOF), increases with increasing vanadium content. Diffuse Reflectance UV VlS (DRUWIS) shows that in samples with a high vanadium content a second type of vanadium species is present that probably is responsible for the observed higher catalytic activity

Structural and mechanistic aspects of the epoxidation of allylic alcohols by VAPO molecular sieve

A conference report. Vanadium aluminophosphate mol. sieves (VAPO-5 and VAPO-11) were tested as heterogeneous catalysts for the epoxidn. of allylic alcs. [on SciFinder (R)

Structural and mechanistic aspects of the epoxidation of allylic alcohols by VAPO molecular sieve

A conference report. Vanadium aluminophosphate mol. sieves (VAPO-5 and VAPO-11) were tested as heterogeneous catalysts for the epoxidn. of allylic alcs. [on SciFinder (R)