| Phenol is important fine chemical intermediates with high economical value.Until now the phenol production is still growing.The traditional methods of producing them always have multi-step reactions,complicated process and many by-products and other contaminations.It is inconsistent with the strategy for sustainable development.Recently, people have cared more about the environment and resource,especially,with the rapid development of Green Chemistry,people concern more and more about how to improve the atomic efficiency,and how to use catalyst to replace the traditional reagent in chemical synthesis.The direct catalytic hydroxylation of benzene to phenol using benzene as the raw material,needs only one step from benzene to the final product.This reaction is directly connected to the activation of C-H bond on aromatic ring.This is one of the most important subjects that deserve detailed investigation.In addition,it is also one of the most difficult problems in synthetic chemistry.In order to realize this goal,the design and preparation of effective catalysts are fatally important.In this thesis,one kind of new type visible light optical catalysts of hydroquinone-like body construction non-nitrogen iron complex absorbed on carrier in a scattered way was prepared by facile impregnation method.The structure properties of samples were characterized by TEM-EDX,IR,the results showed that the as-prepared compounds were Fe (Ⅲ) complex bearing 5-sulfosalicylic acid ligands immobilized carrier structure.The active center of catalyst is composition of hydroquinone-like ligand and Fe3+ ion.Catalyst can effectively catalyze H2O2 to break down into·OH under visible light.Inverted hydroquinone-like structure can drive central iron ion to run through and react in two phases and avoids ineffective decomposition of H2O2 caused by Fe3+ in general Fenton reaction. Catalyst has high activation and long service life and can be widely used in hydroxylation of aromatic ring evoked by hydroxyl radical.In this thesis,H2O2 as oxidizer was used in the oxidation of benzene.The experiments showed that catalysts exhibited different catalytic activity when different supports were used, and catalyst supported onγ-Al2O3 showed the highest activity,thin layer chromatography silica gel(G60) took second place.Through the study of the effect of Fe(Ⅲ)-ssal-Al2O3 and Fe(Ⅲ)-ssal-thin layer chromatography silica gel(G60) catalyst preparing conditions on the activity,the suitable conditions were concluded.Catalytic reaction conditions were investigated thoroughly,Fe(Ⅲ)-ssal-Al2O3 catalyst provided the best result with 100% conversion of benzene and 27.64%selectivity for phenol.The results of the recycling experiment shows that the catalyst Fe(Ⅲ)-ssal-Al2O3 could be reused 6 times,and in first 4 uses time the catalytic activity has not reduced nearly.The catalytic activity of Fe(Ⅲ)-ssal-thin layer chromatography silica gel(G60) was investigated and the reaction conditions were optimized.It provided the best result with 100%conversion of benzene and 21.62%yield of phenol.The results of the recycling experiment showed that the catalyst could be reused 4 times,and in first 3 uses time the catalytic activity has not reduced nearly. In addition,we supposed the reaction mechanism for the photooxidation of benzene to phenol with catalyst we prepared in this thesis.
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