Luffa Sponge And Luffa Sponge-ferrite Compound Materials

Marine pollutants are mainly heavy metal pollution,organic pollution,and oil spills.These types of pollutants generally are removed with chemical catalytic degradation and physical adsorption method.In order to solve this challenge,this study is intended for the investigation and development of water treatment materials and electromagnetic(EM)wave absorbing materials for future use in marine pollutant treatment as well as electromagnetic shielding.It provided the experimental basis based on the hierarchical porosity structure characteristics of luffa sponge.Firstly,the luffa sponge was heated from 400 ? to 700 ? under air and nitrogen.The effects of temperatures and the atmospheres on its morphology,BET surface area,total pore volume and mesopore volume were systematically analyzed,and the experiment of methylene blue(MB)adsorption performance of the samples were conducted Atmospheres and temperatures have only small effects on the content of main elements such as carbon,oxygen and potassium.The luffa sponge is more stable in pyrolysis under nitrogen than under air,and the nitrogen condition also has higher yield.Both LSA and LSN are amorphous and porous materials.High temperature results in the as-prepared samples with high specific surface area and total pore volume.Among all samples,A700 performed best in the experiment of MB adsrorption,with the highest removal at approximately 99.8%.Secondly,luffa sponge-ferrite composite(LSF)was prepared by using luffa sponge as the carrier.Its morphology,pore characteristics,and electromagnetic parameters were characterized,and its electromagnetic wave absorption performance were systematically analyzed.The luffa sponge formed channels with size of micron level,in which the ferrite Fe3O4 attached to the inner surface of the channels.Electromagnetic wave absorption performance ranks from strong to weak as:F500>A700>F600>F400>F700.The RL<-5 dB and RL<-10 dB bandwidth of F500 are 7.5 GHz and 2 GHz,respectively.The RL<-5 dB bandwidth of A700 is 11.2 GHz.The maximum RL and optimum thickness of F500 are-20 dB and 8 mm,and these figures of A700 are-8.0 dB and 2.3 mm.This conclusion indicates that impedance and electromagnetic parameters are the key factor of good EM wave absorber.Through this study,luffa sponge and LSF indeed have great potential application value in the treatment of marine pollutants and as EM wave absorbing materials.