Study On The Preparation And Performance Of High-efficiency Air Filtration Nanofiber Membrane

Environmental control is extremely urgent,especially air pollution.In recent years,nanofilament membrane prepared by electrospinning technology has been used as a filtration material with remarkable filtration effect.However,most materials can only meet People’s Daily needs,and can not effectively filter the high-temperature waste gas produced in industrial production.As an amorphous polymer material with high performance,PASS has high service temperature and excellent acid and alkali resistance.In this paper,polyaryl sulfone nanofiber membrane was prepared by means of electrospinning technology.Firstly,the process parameters of electrospinning were optimized,and then the influence of different concentrations of PASS spinning solution on the microscopic morphology of the membrane and fiber diameter was investigated.At the same time,the pore diameter distribution of the membrane was tested.Finally,air filtration experiments were carried out on different concentration membranes.The results showed that the electrostatic spinning film with small diameter and independent fibers could be obtained with the acceptance distance of 35cm and the voltage of 20kV.The concentration has a great influence on the morphology and structure of PASS nanofiber membrane.When the spinning solution concentration is 0.21g/ml and 0.24g/ml,the nanofiber membrane with beaded structure can be obtained.When the concentration of spinning solution was 0.27g/ml and 0.30g/ml,the nanofiber membrane produced only had fiber structure.The mechanical properties of the PASS nanofiber membranes prepared with different concentration of spinning solution are general,hydrophobic materials,and the contact Angle is above 120°.The results of air filtration test showed that the filtration efficiency of PASS nanofiber membrane prepared with different spinning solution concentrations on particles larger than 500nm reached more than 90%.The quality factor of PASS nanofiber membrane with spinning solution concentration of 0.27g/ml reached the highest 0.03563,the pressure drop was only 44Pa,and the comprehensive air filtration performance was the best.At the same time,the prepared PASS nanofiber membrane was oxidized,and the morphology and structure of the oxidized nanofiber membrane were observed.The changes of functional groups and element contents on the fiber membrane were characterized by infrared and XPS,and the related properties of o-pass and PASS nanofiber membrane were compared.The results showed that in the oxidation process,the sulfur ether bond on the PASS molecular chain was oxidized to sulfoxide group and sulfoxide group,and the heat resistance and acid-base corrosion resistance of the PASS nanofiber membrane were further improved.Under electron microscope,the morphology and structure of the oxidized PASS nanofiber membrane did not change significantly,nor did the fiber diameter.The pore diameter test showed that the average pore diameter of the corresponding PASS nanofiber membrane decreased after oxidation.The mechanical test results showed that the tensile strength of the oxidized PASS nanofiber membrane increased 2-3 times,but the material became brittle.The results of contact Angle showed that the water contact Angle of the oxidized PASS nanofiber membrane was slightly improved and hydrophobicity was enhanced.In air filtration tests,we investigated the effects of wind speed,solvent,temperature and base weight on o-pass nanofiber membranes.The results showed that the wind speed and base weight had a great influence on the pressure drop in air filtration,and the o-pass nanofiber membrane could still maintain a high filtration efficiency after acid,alkali and organic solvent or high-temperature treatment,and could withstand corrosion and high temperature of acid,alkali and solvent to a certain extent.After adding silica of inorganic nano particles,we can get PASS nano fiber membrane with super hydrophobic property,which will make the dust removal effect of the fiber membrane more excellent,and extend the service life of PASS nano fiber membrane.