Studies On Selenium-catalyzed Reduction Of M-dinitrobenzene To M-nitroaniline

m-nitroaniline is a kind of useful organic intermediate.It is widely applied to prepare dye,pharmaceutical compounds,and other organic products.Currently there are many methods to produce the intermediate in industry,such as iron powder reduction,sodium sulphide reduction,and catalytic hydrogenation reduction,etc.Using iron to undertake the production reduction has some advantages such as easily controlled,simple process,and reasonable technical economy.The disadvantages are that it produces a large amount of waste water containing amine.It is difficult to deal with the iron sludge waste residue,and it will cause environmental pollution and labor intensity.Sodium sulphide reduction method will react mildly,the selectivity is better,the separation of the product is more convenient,but it produces a large amount of liquid,which is hard to deal with and can cause environmental pollution.Catalytic hydrogenation method has some advantages,such as large output,high quality,less waste,easy post-processing,and helpful to solve the environmental pollution.It is also a green technology to the friendly environment.Generally,the catalyst selection of catalysis hydrogenation is poor and hard to be used in the original nitro compounds.Meanwhile the hydrogen preparation,storage and transportation also have certain difficulties.The metal catalyst in hydrogenation reduction method is easy to bring generation acid material that will corrosion the equipment.Therefore,we need a kind of method,which is less pollutional,more selectivity,and more convenient to prepare.Since 1980,Japanese scholar Sonoda found the Se/CO/H2O catalytic system,and ever since,it has been found that this system has high conversion and selectivity to nitro compounds reduction.The goal of this paper is to further develop the Se/CO/H2O catalyzed system and to apply Se/CO/H2O catalytic system to the production of the intermediate-m-nitroaniline.Comparing with traditional methods,the new way to prepare m-nitroaniline is more effective for environmental and more economical.We chose that under high-pressure condition,using the Se/CO/H2O catalytic system to reduce m-dinitrobenzene.Firstly,we prefer water as the reaction solvent to adding any of the organic solvent.Then,the optimal reaction conditions were determined by a large number of condition experiments.This paper is divided into five parts.The first part is a review,which mainly introduces the application of m-nitroaniline and the method of preparation.The second part introduces the process of the experiment.The third part,we do a lot of condition experiments to get optimum reaction conditions,and the highest yield is 92.4%.In the fourth part,we study appropriate reaction temperature by discussing its reaction kinetics.The final part summarises the whole work in this paper.