Study On The Mechanism Of Removal Of Nitrobenzene And Arsenic Acid By Amorphous Zero-valent Iron

With the rapid development of China,the water environment problem in China has become increasingly serious,and the current commonly used water treatment technology can not meet the needs of dealing with complex polluted water bodies.Zero-valent iron treatment technology is widely used to deal with water environment problems because of its wide applicability,low cost and easy availability,and it is still widely used to deal with water environment problems.It is necessary to develop new strategies to improve the response capability..Previous studies have found that amorphous materials have a high degree of coordination and unsaturation due to their disordered atomic arrangement and thus have more active centers.Therefore,amorphous materials tend to have excellent chemical reaction properties,which is undoubtedly for us.A new idea of amorphizing zero-valent iron to increase its activity is provided.Therefore,we obtained zero-valent iron with amorphous structure by controlling the reduction process,and then used nitrobenzene and aspartic acid as target pollutants respectively.The amorphous structure of zero-valent iron p-nitrobenzene and aspartic acid was systematically studied.The removal mechanism is used to investigate the properties of the zero-valent iron oxidation,reduction and adsorption properties of amorphous structures.The main contents of the paper are as follows:(1)We explored the mechanism by which amorphous structures affect the removal of nitrobenzene by zero-valent iron.By studying the difference between the process of reducing and removing nitrobenzene by amorphous and crystalline zero-valent iron,we found that amorphous zero-valent iron has excellent reactivity compared with crystalline zero-valent iron,and the two ways of decomposing nitrobenzene by zero-valent iron are obvious.The difference.The main way to degrade nitrobenzene by amorphous zero-valent iron is to directly reduce nitrobenzene to aniline by Fe0,relatively less contribution of Fe2+;while the degradation of nitrobenzene by crystalline zero-Valent iron is mainly by surface-adsorbed Fe2+.Nitrobenzene.In addition,we systematically studied the adsorption capacity and degradation path of amorphous structure zero-valent iron on nitrobenzene and the influence of environmental factors on amorphous zero-valent iron.(2)The mechanism of the effect of amorphous structure on the removal of oxalic acid by zero-valent iron was discussed.The experimental results show that the amorphous structure can greatly improve the oxidation performance of zero-valent iron on arsenic acid and the adsorption capacity of inorganic arsenic.Superoxide radicals are the main active oxygen species of amorphous and crystalline zero-valent iron degrading arsenic acid.The amorphous structure can promote zero-valent iron to activate molecular oxygen and efficiently produce reactive oxygen species,thereby improving its performance of degrading oxalic acid.At the same time,the amorphous structure can greatly enhance the ability of zero-valent iron to adsorb inorganic arsenic,which is conducive to the fixation of inorganic arsenic.Based on the analysis of arsenic morphology and the determination of intermediates,we propose a possible degradation pathway of oxalic acid in amorphous zero-valent iron system.