3D Electrode Based On Graphene Aerogel For Removal Of Organic Pollutants In Wastewater

With the development of industrialization,water pollution is becoming more and more serious.Traditional sewage treatment methods are difficult to degrade sewage with large concentration and various organic substances.It is extremely urgent to develop new sewage wastewater treatment technology.Electrochemical techniques has attracted more and more attention because of its simple operation,simple equipment and no secondary pollution.With the increase of pollutant concentration and types,the traditional two-dimensional electrode technology has many limitations in mass transfer and degradation process,but the three-dimensional electrode technology greatly improves the specific area and mass transfer.The particle electrode in the three-dimensional electrode reactor has the functions of adsorption,electrochemical degradation,and so on.It plays an important role in the whole reaction system.Preparation of particle electrodes with high adsorption,good hydrophilicity and conductivity has become a notable question.This research paper mainly consists of two parts,using low temperature hydrothermal self-assembly and freeze-drying method to prepare graphene aerogel and its composite,which is used as a particle electrode to construct a three-dimensional electrode reactor to improve the degradation ability of wastewater.This paper mainly includes two parts:1.Graphene aerogels with abundant macroporous structure were prepared by low temperature hydrothermal self-assembly and freeze-drying method.Three-dimensional electrode reactor with the particle electrodes use to degrade methylene blue,and its degradation ability?98%?is much higher than that of adsorption of graphene aerogels?82%?and two-dimensional electrode?89%?.And it has a good treatment effect on the sewage containing phenol and rhodamine B,which proves that it is universal to the degradation of sewage.Parameters affecting the degradation efficiency of the graphene aerogels,such as concentrations of graphite oxide,calcination temperature,voltage,air flow and initial methylene blue concentration were examined.Results showed that the optimal conditions were 6mg/mL graphite oxide,no calcination,20V voltage,20mL/min air flow and 20mg/L methylene blue initial concentration.2.FeOOH/GA composites were prepared through an in-situ Fe²⁺-reduction induced self-assembly and deposited process,by hydrothermal synthesis and freeze-drying method.Three-dimensional electrode reactors with FeOOH/GA were constructed for the degradation of methylene blue in water.It was revealed that the degradation capacity of the FeOOH/GA aerogel?94%?surpasses those of graphene aerogel adsorption?64%?,two-dimensional electrode?72%?,three-dimensional electrode with GA?84%?.Finally,the influence of different iron loading on the processing capacity was explored.It was found that when the mass ratio of graphite oxide to ferrous sulfate heptahydrate was 1:30,the treatment performance was the best.