Preparation Of Functional Fiber Membrane And Its Application In Air Filtration And Oil Absorption

With the rapid development of technology and industry,air pollution has become more and more serious.Air pollution has become a global concern.The air particle pollution caused by increasing industrialization poses a huge threat to public health.Therefore,it is extremely urgent to develop an efficient and high-performance green air filter.With the development of industrialization,mankind is extracting more and more oil,especially offshore oil.The most economical way to transport oil is ocean transportation.Therefore,the phenomenon of offshore oil leakage continues to increase,which is a global environmental problem.Because it has caused a serious negative impact on the ecosystem.First,by introducing an ultra-thin polyvinylidene fluoride(PVDF)nanofiber layer on the filter material,using the spinning bead spinneret electrospinning technology,a high-performance PM_2.5 capture and high-yield(1000 m²/d)filter material.Electrospun PVDF nanofibers have a strong ability to trap and attract PM,and the filtration efficiency of the filter material for PM_2.5is significantly improved(69.958%?98.161%).The composite filter has a higher air flow rate(278.4 mm s^-1)and a lower pressure drop(30 Pa).Long-term filtration and ventilation rate tests show that the composite filter membrane has a stable high filtration efficiency(98.137%?96.36%)and ventilation rate.Electrospun PVDF fiber also has a certain degree of hydrophobicity,which can effectively improve the long life of the composite filter material.This high-performance composite nanofiber membrane will become a promising filter for large-scale PM_2.5 capture production and personal health protection.Then a new type of oil-absorbing membrane was introduced.First,the polyphenylene sulfide film is prepared by melt-blowing method,and then the graphene oxide is prepared by the improved Hummers method.A graphene oxide aqueous solution with a dilution ratio of 1:1 is configured,and 6 polyphenylene sulfide films of the same size are put into deposit 2 times,4 times,6 times,8 times,and 10 times respectively in the prepared graphene oxide aqueous solution.Then,the polyphenylene sulfide film deposited in the graphene oxide aqueous solution 2 times,4 times,6 times,8 times,and 10 times was reduced with hydroiodic acid for 24 hours.The resistance test knows that the resistance of the polyphenylene sulfide film deposited 2 times,4times,6 times,8 times,and 10 times decreases with the increase of the number of depositions.Experiments have found that the membrane has good adsorption performance for chloroform and kerosene,and the measured fluxes are all greater than5000 L m^-2h^-1.The membrane can be used under strong acid and strong alkali conditions,and has the ability to resist harsh environments.Applying voltage to the membrane can make the oil thinner and improve the efficiency of oil absorption,which uses the conductivity of graphene.By looking at the resistance drop slope,it is found that the slope becomes smaller after 6 times,and then according to the similar size of the contact angle of each membrane,the flux becomes smaller as the number of times increases,and the rejection rate is not much different than 99%.Therefore,the film deposited six times is selected as the optimal film for comprehensive flux and resistance.In summary,it can be seen that the membrane can not only resist harsh environments such as strong acids and alkalis,but also has excellent oil absorption ability.The use of Joule heat generated by electric heating greatly increases the original rate of adsorption,and brings unlimited potential to the study of oil-water separation.