Font Size: a A A

Selective Photooxidation Of Cyclohexene And Cyclohexane

Posted on:2008-01-07Degree:MasterType:Thesis
Country:ChinaCandidate:X J XueFull Text:PDF
Abstract/Summary:PDF Full Text Request
Organic synthesis is one of indispensable parts in chemical industry. Traditional methods and technique not only consume lots of energy source, but also make the environment easily be contaminated by such as toxic organic solvents. Thus photocatalytic technique, which aims to use solar light as energy, oxygen as oxidant and run at ambient temperature and pressure, is a green technique. Application of photocatalytic technique to organic synthesis would be a valuable research. In this thesis, selective oxidation of cyclohexene and cyclohexane has been studied using different photocatalyst of metal phthalocyanine and titanium dioixed in an aerated aqueous solution.Four chapters are included in this thesis. Chapter 1 is an introduction about the principle and progress of photocatalytic technique. Chapter 2 is a review of the recent progress achieved on the selective photooxidation of cyclohexene and cyclohexane. In chapter 3, the selective photooxidation of cyclohexene by using metal phthalocyanine as a visible light sensitizer has been studied in a mixed water and organic solvents. In chapter 4, the effect of NaF addition on the TiO2-photocatalytic oxidation of cyclohexane has been studied.For the cyclohexene oxidation, metal phthalocyanines exhibit a good activity. The reaction gives hydroperoxidate cyclohexene as the main product, which is mainly formed through singlet oxygen. The product yield and selectivity and the catalyst stability are all greatly depend on the central metal in phthalocyanine complex, organic solvent and water content in the mixed solvent. Comparatively, PdPcS displays an excellent performce in acetonitril-water (v:v 85:15) in terms of all the photoactivity, product selectivity and stability.For the TiO2-photocatalytic oxidation of cyclohexane, addition of NaF into the aqueous dispersion results in an obvious change in the catalyst photoactivity and in the product selectivity. Such effect is only positive with anatase TiO2, but it is negative with rutile TiO2 under similar conditions.
Keywords/Search Tags:metallophthalocyanine, titanium dioxide, cyclohexene, cyclohexane, photocatalyst
PDF Full Text Request
Related items