- U. Hanefeld (1)
- J.C. Jansen (2)
- T. Maschmeyer (3)
- J.A. Moulijn (1)
- G. Mul (1)
- R. Parton (2)
- F. Peter (1)
- A. Ramanathan (1)
- J.P.M. Sanders (2)
- E.L. Scott (2)
A novel photocatalytic conversion of Tryptophan to Kynurenine using black light as a light source
Hamdy Mohamed Saad, M.S. ; Scott, E.L. ; Carr, R.H. ; Sanders, J.P.M. - \ 2012
Catalysis Letters 142 (2012)3. - ISSN 1011-372X - p. 338 - 344.
amino-acids - human lens - photooxidation products - wool proteins - photochemistry - constituents - degradation - ozone - mass
The photocatalytic conversion of an aqueous solution of l-tryptophan (Trp) to kynurenine (KN) was investigated under the illumination of different light sources. Results show that Trp converted to KN with a selectivity of 64% under the illumination of a medium pressure (MP) Hg lamp. KN selectivity was increased to >90% when black light (BL) was used a light source. The novel use of BL in the photocatalytic conversion of Trp to KN significantly reduces the energy consumption compared with MP light
Metal-TUD-1 Catalyzed Aerobic Oxidation of Cyclohexane: A Comparative Study
Anand, R. ; Hamdy Mohamed Saad, M.S. ; Parton, R. ; Maschmeyer, T. - \ 2009
Australian Journal of Chemistry 62 (2009)4. - ISSN 0004-9425 - p. 360 - 365.
liquid-phase oxidation - heterogeneous catalysts - selective oxidation - incorporated tud-1 - by-products - autoxidation - performance - decomposition - co-tud-1 - propane
The relative performance of various metal-incorporated mesoporous silicas of the TUD-1 structure type (M-TUD-1, where M = Ti, Cr, Co, Fe, Cu, Mn) in the selective aerobic oxidation of cyclohexane with tert-butylhydroperoxide and cyclohexylhydroperoxide (CHHP) to the respective hydroperoxides and subsequent decomposition to the alcohol and ketone is reported. In particular, relationships regarding metal type and loading, silica structure type and peroxide initiator are elucidated, to show that it is possible to tune catalysts for either CHHP formation or CHHP decomposition
Process for converting tryptophan into kynurenine
Sanders, J.P.M. ; Peter, F. ; Scott, E.L. ; Hamdy Mohamed Saad, M.S. ; Carr, R.H. - \ 2009
Octrooinummer: WO2009135843, verleend: 2009-11-12.
A process for converting tryptophan into kynurenine. Theconversion of tryptophan into kynurenine is carried out by irradiating a substance comprising tryptophan with electromagnetic radiationcomprising waves withwavelength in the range of 10 nanometer to 750 nanometer.
Co-TUD-1 catalysed aerobic oxidation of cyclohexane
Ramanathan, A. ; Hamdy Mohamed Saad, M.S. ; Parton, R. ; Maschmeyer, T. ; Jansen, J.C. ; Hanefeld, U. - \ 2009
Applied Catalysis A-General 355 (2009). - ISSN 0926-860X - p. 78 - 82.
liquid-phase oxidation - containing molecular-sieves - selective oxidation - by-products - autoxidation - oxygen - alkanes - fe - co
Co-TUD-1, an amorphous sponge-like mesoporous cobalt-containing silicate, was shown to be a very active and selective catalyst for the aerobic oxidation of cyclohexane. In addition, the decomposition of cyclohexyl hydroperoxide (CHHP) was carried out over Co-TUD-1 and it catalysed complete conversion of CHHP with excellent selectivity towards cyclohexanol and cyclohexanone. A stable activity over a period of one week was established for Co-TUD-1 in our rigorous leaching experiments during the continuous decomposition of CHHP. No leaching of the metal could be detected proving the catalyst to be truly heterogeneous. (C) 2008 Elsevier B.V. All rights reserved.
Chromium-incorporated TUD-1 as a new visible light-sensitive photo-catalyst for selective oxidation of propane
Hamdy Mohamed Saad, M.S. ; Berg, O. ; Jansen, J.C. ; Maschmeyer, T. ; Arafat, A. ; Moulijn, J.A. ; Mul, G. - \ 2006
Catalysis today 117 (2006)1-3. - ISSN 0920-5861 - p. 337 - 342.
containing mesoporous silica - metal-oxide surfaces - photocatalytic reaction - irradiation - combustion - no - dehydrogenation - hydrocarbons - reduction - zeolite
Chromium was incorporated in the framework of TUD-1 mesoporous silica by a one-pot synthesis procedure, using triethanolamine as a bi-functional template. The Cr-TUD-1 catalyst was characterized by means of X-ray diffraction, high-resolution transmission electron microscopy, UV¿vis and Raman spectroscopy, as well as elemental analysis and N2 sorption measurements. The results indicate that chromium is incorporated as tetrahedrally co-ordinated Cr6+ in the framework of TUD-1. When tested as a catalyst for the photo-oxidation of propane, Cr-TUD-1 showed high activity and high selectivity towards acetone under visible light irradiation (¿ = 435 nm).