Photocatalytic Selective Oxidation of 4-Methoxybenzyl Alcohol to Aldehyde in Aqueous Suspension of Home-Prepared Titanium Dioxide Catalyst
نویسندگان
چکیده
The photocatalytic oxidation of 4-methoxybenzyl alcohol to p-anisaldehyde (PAA) was performed in water with organic-free suspensions of home-prepared and commercial titanium dioxide (TiO2) catalysts. The nanostructured TiO2 samples were synthesised by boiling aqueous solutions of titanium tetrachloride (TiCl4), under mild conditions, for different times. The crystallinity increased with the boiling time. The 4-methoxybenzyl alcohol oxidation rate followed the same pattern but the highest yield (41.5% mol) to PAA was found for the least crystalline sample, that showed a quantum efficiency of 0.116%. A comparison with two commercial TiO2 samples showed that all the home-prepared catalysts exhibited a PAA yield higher than that of commercial ones. The only by-products present were traces of 4-methoxybenzoic acid and aliphatic products, carbon dioxide being the other main oxidation product.
منابع مشابه
Alcohol‐Selective Oxidation in Water under Mild Conditions via a Novel Approach to Hybrid Composite Photocatalysts
The oxidation of alcohols to carbonyl compounds in a clean fashion (i.e., with water as a solvent or under solvent-free conditions, and using O2 or H2O2 as the primary oxidant) is the subject of considerable research efforts. A new approach for the selective oxidation of soluble aromatic alcohols in water under mild conditions via a novel composite photocatalyst has been developed. The catalyst...
متن کاملCore–shell titanium dioxide /carbon nanofibers decorated nickel nanoparticles as supports for electrocatalytic oxidation of ethanol
Abstract Recently alcohol fuel cells has been increased consideration because of their environmental friendliness, high energy conversion efficiency and low emissions. Many effort have been made to improve the electro-oxidation performance of alcohols such as methanol, ethanol and propanol. In this work, a new method for ethanol oxidation based on core–shell titanium dioxide / carbon nanofib...
متن کاملPhotodegradation process for the removal of acid orange 10 using titanium dioxide and bismuth vanadate from aqueous solution
In this study, the photocatalytic degradation of azo-dye acid orange 10 was investigated using titanium dioxide catalyst suspension, irradiation with ultraviolet-C lamp and bismuth vanadate under visible light of light-emitting diode lamp. Response surface methodology was successfully employed to optimize the treatment of acid orange 10 dye and assess the interactive terms of four factors. The ...
متن کاملPhotocatalytic oxidation of 2,6-dichloroindophenol in the titanium dioxide aqueous suspension
Photocatalytic oxidation of sodium salt of 2,6-dichloroindophenol (DCIP) in titanium dioxide aqueous suspension has been studied. DCIP is photocatalytically oxidized on the active Ti02 surface by the medium pres sure Hg lamp with pyrex sleeve radiation (A>280nm). The apparent integral quantum yield of the DCIP decomposition was determined. Photocatalytic decomposition of DCIP in aqueous suspen...
متن کاملSelective oxidation of sulfides to sulfoxides by a vanadium-based catalyst using 30% hydrogen peroxide
The vanadium-based catalyst, acts as a homogeneous catalyst for the selective oxidation of various kinds of sulfides with 30% aqueous H2O2. Vanadium-based catalyst was successfully used as the oxygen source for the oxidation of sulfides to sulfoxides for the first time. The sulfoxides were obtained in a good way to high yields without any detectable over-oxidation to sulfones under normal condi...
متن کامل