Study On Chemical Modification Of Tourmaline Powder And Its Application In Water Treatment

With the progress of industry and the development of science and technology,people’s pursuit of a better life is getting higher and higher,which requires life to be improved from all aspects.The source of life begins with water,and it is very important to have pure water.We notice different sources of water pollution:on the one hand,the textile dye industry.Dyes are developing towards oxidation resistance,light resistance,temperature resistance,rich and bright color,which brings great trouble to dye degradation.On the other hand,the use of a large number of antibiotics,antibiotics have been widely used in veterinary,agricultural and human treatment.However,due to the nature of antibiotics,humans and animals are able to metabolize very little,resulting in large amounts of their residues being released into the environment.In terms of degradation of organic pollutants,Fenton-like system is a very important means of advanced oxidation and degradation system,because of its inherent limitation of degradation saturation,which reduces the scope of application.The catalytic degradation effect of titanium dioxide（TiO₂）under ultraviolet light is excellent.Because of its narrow spectral utilization range,the application range is also greatly reduced.Carbon nitride（g-C₃N₄,CN）is a kind of graphite material,excellent photocatalytic activity,high chemical stability and thermal stability,appropriate band gap,but pure CN shortcomings are high carrier recombination rate,poor electrical conductivity,small specific surface area,limited visible light absorption.In this paper,tourmaline（Tour）,a natural mineral,is selected as the raw material to improve the catalytic activity of the system by combining it with different materials with catalytic performance.The research work of this paper is as follows:（1）Negative ion powder（NIP）@Fe₃O₄ composite was prepared by precipitation method.NIP accelerated the Fe（Ⅲ）/Fe（Ⅱ）redox process to improve the catalytic activity.The Zeta potential of the composite is negative under alkaline condition,and the electrostatic interaction with methylene blue（MB）is enhanced,so the catalytic effect is improved.The active substances in the catalytic system are mainly electrons and oxygen free radicals.The far infrared properties of NIP can activate water molecules,The electric field on the surface of the NIP makes the electrons generated by the system move in a directional way,which accelerates the reduction of Fe（Ⅲ）,thus improving the activity of the catalyst.（2）Tourmaline/Zinc ferrite-TiO₂（Tour/ZFO-TiO₂）photocatalytic composites were prepared by sol-gel method.The band gap of ZFO is 1.9 eV,smaller than that of TiO₂,and z-transfer can occur between the two.The permanent,spontaneous electrical polarity of Tour can trap electrons and prolong their lifetime,thus preventing rapid recombination of electron and hole pairs.The composite material has certain magnetic properties,which makes the material recycling more convenient.Under the loading of ZFO-TiO₂,the agglomeration of Tour decreases,and the specific surface area of the composite increases.When the composite contains a large amount of Tour,the catalytic effect is poor.（3）Tour/CN photocatalytic composites were prepared by calcination method.CN has a suitable band gap（2.7eV）and a large specific surface area,which can be loaded on the Tour surface to increase the specific surface area of Tour complex.CN itself has a good catalytic effect on oxytetracycline hydrochloride（OTC）,and the degradation effect of the composite with 12%CN content can reach 75%of that of pure CN.Tour plays an important role in reducing the recombination of photogenerated electrons and hole pairs of CN...