Adsorption Of Sulfonamide In Water By Graphene And Photocatalytic Regeneration

Among the adsorption process materials,graphene materials with large specific surface area and strong adsorption properties are used in adsorption treatment of pollutants.However,due to the limitations of the currently used regeneration methods,it has become a limitation for its wide application.Big factor.In order to solve the problem of regeneration of graphene as an adsorbent,this study proposes two methods for the regeneration of graphene.One is to carry out regeneration by sodium sulfonate sulfonate solution,and the other is to load graphene-yttrium composite material by loading yttrium-2-sulfonate sodium on the surface of graphene by ?-? stacking method.The photocatalytic process is carried out under illumination to achieve in-situ regeneration of the graphene-bismuth composite.The properties of the sulfapyridine contaminants adsorbed by the two materials and the regeneration efficiency after adsorption saturation were analyzed.The research contents are as follows:Firstly,the pure graphene material was used as adsorbent to adsorb sulfapyridine pollutants.The adsorption study showed that the kinetic composite pseudo-second-order kinetic model of the adsorption process;the adsorption isotherm fitting was similar to the Langmuir model,indicating the graphene pair.The adsorption process of pollutants was single-layer adsorption.The maximum adsorption capacities were 227.27,250.16 and 263.16 mg/g under the conditions of 288,298 and 308 K respectively.The thermodynamic results of graphene adsorption indicated that physical adsorption dominated the reaction.The position,and the reaction endothermic;the photocatalytic regeneration of graphene is carried out by using high-efficiency photocatalytic performance as a regeneration solution,and the regeneration rate,enthalpy load and loss rate are used as evaluation indexes,and different factors are analyzed for the solution light.The effect of catalytic graphene effect,the experimental results show that the regeneration rate increases first and then decreases with the increase of the concentration of regeneration solution,and the loss of regeneration solution increases,the optimum concentration of regeneration solution is 30 mg/L;The regeneration process has good stability in the regeneration process,and the regeneration efficiency decreases with the increase of the number of repetitions,but regeneration After 5 times,it can still reach 68% or more.The optimal regeneration time is 9 h.Considering the economic and energy consumption problems,the regenerated adsorption dose of 20 mg is the best condition.Secondly,in order to realize the in-situ regeneration of graphene,reduce the loss and enhance the repetitive utilization rate,the graphene-ruthenium composite material was prepared by ?-? stacking method on the surface of graphene,and the composite was characterized.Ruthenium was successfully loaded on the surface of graphene by ?-? stacking method,but the loading of ruthenium occupied the adsorption site of graphene surface,but had little effect on its structure and properties.The adsorption properties of the composites were studied.It was found that the increase of the amount of ruthenium materials caused the adsorption performance to decrease.The adsorption kinetics of the pollutants was in accordance with the pseudo-secondary kinetics.The Langmuir model was the closest adsorption isotherm after fitting.At the temperature of 288,298,and 308 K,the maximum adsorption capacity of the composites to the pollutants was 51.28,72.46,and 76.92 mg/g,respectively.The adsorption process was found to be a spontaneous physical adsorption process through thermodynamic studies.The in-situ regeneration results of the composites showed that the best effect was obtained when the ruthenium loading was 243.69 mg/g,the material dosage was 20 mg,and the regeneration time was at least12 h.At the same time,the synergistic effect of adsorption-photocatalytic regeneration was observed.The removal process of sulfapyridine can be carried out continuously and efficiently.The removal rate after 5 cycles is still 95% of the initial performance,and the performance is stable.The whole photocatalytic process is combined by superoxide and superchlorine.Occurred,the reaction process is more thorough,and the cleaning does not produce intermediate products.Experimental studies have shown that the step-by-step regeneration method using sodium sulfonate-2-sulfonate as a regeneration solution and the in-situ regeneration method for preparing graphene-ruthenium composite can effectively remove the pollutants adsorbed on the adsorbent to achieve Compared with the two,the in-situ regeneration method has a large total amount of pollutants removed,no need to transfer,and is more suitable for large-scale sewage treatment;and the step regeneration method of the regeneration solution does not need to prepare materials,and the lighting conditions are required.The lower,suitable for regional light duration is shorter,in the process of small-scale sewage treatment.