The Study On Adsorption Behavior Of SDZ And Phenol Onto Microplastics In Sea Water

Microplastics refer to plastic particles with a particle size of less than 5mm.In recent years,microplastics have been frequently found in a wide range of natural environments,marine organisms and human drinking water.Because of the hydrophobic properties of plastic,it is very easy to enrich or concentrate organic pollutants in the environment and form combined pollution.Microplastics can be used as a carrier to transport these pollutants to remote areas or be eaten by organisms result in pollutants into organisms body,and then increase the toxic effect on organisms.Antibiotics have saved countless lives since they were discovered in the 20th century,but due to excessive use,they have affected the microbial community in the environment and caused the generation of drug resistance genes,the emergence of "super bacteria" much made people's panic worse over the abuse of antibiotics.As two emerging pollutants,microplastics and antibiotics have been widely concerned by human society.The use attributes of microplastics and antibiotics make sewage tre'atment plants have no effective interception measures against them.A considerable number of microplastics and antibiotics finally enter the marine environment every year.Whether the two pollutants will bring "1+1>2" pollution effect in the marine environment is becoming a topical issues.Not just antibiotics and microplastics in the ocean,the existence of organic pollutants in the ocean cannot be ignored.Therefore,this article focuses on the competitive adsorption of antibiotics and organics onto microplastics.Sulfadiazine is an important antibiotic drug,and a large amount of sulfadiazine enters the seawater system every year.Phenol,as a traditional organic pollutant,is also frequently detected in the seawater environment.In this study,sulfadiazine and phenol were selected as representatives of antibiotics and organic compound to investigate their adsorption behavior on microplastics,and the results showed as follows:(1)The different microplastics had different adsorption for pollutants.PE had a higher affinity to pollutants,and the adsorption capacity of pollutants on PE was 1mg/L more than that on PP.(2)The adsorption of pollutants onto different microplastics was also different.The adsorption capacity of sulfadiazine on microplastics was about 2?4mg/L more than that of phenol on microplastics.(3)The adsorption of PP to pollutants was more in line with the Langmuir adsorption isotherm model,and the adsorption of PE to pollutants was more in line with the Freundlich adsorption isotherm model.(4)The presence of phenol would affect the adsorption capacity of sulfadiazine onto microplastics.As the concentration of phenol increased,the adsorption capacity of sulfadiazine on microplastics decreased in logarithmic from.But the presence of sulfadiazine would hardly affect the adsorption of phenol onto microplastics.