Preparation Of Graphene Oxide Composites By Electrospinning And Its Application As Adsorption Materials

Methylene blue(MB)is a commonly used industrial organic dyes,widely in printing and dyeing,textile and other fields.Methylene blue has a complex molecular structure with a benzene ring,so it is difficult to degrade and it has a certain low toxicity.The main source of heavy metal cadmium(Cd)is mining,metallurgy and other industries.Cd is mainly used in chemical,electroplating,nuclear industry,electronics and other fields.Heavy metal cadmium in polluted water can enter the body through the food chains and accumulate in the body organs which will cause chronic damage,especially for the kidney,severe cadmium pollution may lead to bone softening or osteoporosis.Therefore,water containing methylene blue and cadmium must be effectively treated before being released into the natural environment.Adsorption is proved to be a very effective method of wastewater treatment because of low cost,high efficiency,easy operation and other characteristics.The emergence of carbon nanomaterials has brought new opportunities for the water treatment industry.As an oxidative derivative of graphene,graphene oxide(GO)has some excellent properties,such as large specific surface area and rich oxygen-containing functional groups,which make the graphene oxide be a good adsorbent.In this study,polyacrylonitrile and graphene graphene(PAN/GO)composite fiber films were prepared by the method of electrospinning.The films were characterized by XRD,FESEM,TGA and RAMAN.The morphology and thermal stability of GO and PAN/GO were also analyzed.The adsorption and adsorption mechanism of methylene blue and cadmium were studied.The adsorption capacity of PAN/GO composite fiber to methylene blue was up to 132.35 mg/g,the mass ratio of GO and PAN was 30%.At the same time,the mass ratio of graphene oxide,the initial pH value of the solution,the contact time,the methylene blue concentration and the reaction temperature will have an effect on the adsorption capacity.The adsorption isotherm study showed that the adsorption of PAN/GO composite fibers on methylene blue was well followed by the Langmuir model.The adsorption process of PAN/GO composite fibers on methylene blue is more consistent with the Pseudo-second-order model.Thermodynamic studies show that the adsorption process of PAN/GO composite fibers to methylene blue is a spontaneous endothermic process.The adsorption capacity of PAN/GO composite fibers on adsorption of cadmium ions was 87.98 mg/g.Adsorption isotherm study showed that PAN/GO composite fibers adsorbed cadmium ions well followed the Freundlich model.