Study On Preparation And Filtration Performance Of High Temperature Resistant Nanofibers Containing Aluminum Salt

In recent years,industrial waste gas emission is an important source of air pollution,which directly affects human health.How to effectively remove fine particles from industrial waste gas has become an important measure to control air pollution.Due to its large specific surface area,high porosity and adjustable pore size,nanofibers have more prominent advantages in the field of gas filtration than traditional fiber filters.In this paper,polyvinylpyrrolidone(PVP),polyvinyl alcohol(PVA)and polysulfone amide(PSA)as the matrix,doped with aluminum isopropanol(AIP),aluminum chloride(AlCl₃),aluminum nitrate(Al(NO₃)₃)and boomite(B),were used to prepare aluminum salt high-temperature resistant nanofibers by electrospinning technology.The morphology,aggregate structure,mechanics,thermal properties and filtration properties of high temperature nanofibers containing aluminum salt were systematically studied.The research content are as follows:(1)The PVP-AIP-ethanol blend system was used to prepare the spinning liquid.The PVP/AIP nanofiber membrane was prepared by electrospinning method.The effects of PVP concentration,AIP concentration,spinning voltage,calcination temperature and other parameters on the morphology,structure and properties of nanofibers were studied.The experimental results show that:When 10.0 wt%PVP was used,5.0 wt%AIP was added,the spinning voltage was 18.0 k V,and the receiving distance was 15.0 cm,the performance of the membrane in fiber diameter and pore diameter distribution was relatively good,the filtration efficiency could reach 95.17±0.43%,and the pressure drop was 51±2 Pa.After being treated at 200?for 1 h,the size of the membrane was reduced by 6%,and the filtration efficiency was still relatively high,96.56±0.36%.After calcination at 1200?,alumina nanofibers with fiber diameter of 314±15 nm were formed.(2)Using PVA-AlCl₃-water and PVA-Al(NO₃)₃-water spinning liquid system,PVA based nanofiber membrane containing aluminum salt was prepared by electrospinning technology.By adjusting the concentration of PVA and aluminum salt to adjust the diameter and pore size of the fiber membrane,the dendritic morphology of the nanofiber membrane was successfully prepared and characterized.The experimental results show that when the concentration of PVA is 30.0 wt%and the concentration of aluminum chloride is 20.0 wt%,the pore size of the fiber membrane is 1.01±0.39?m,the filtration efficiency is 97.20%,and the pressure drop is 24 Pa.When the concentration of PVA is 30.0 wt%and the concentration of aluminum nitrate is 20.0wt%,the pore size of the fiber membrane is 1.21±0.26?m,the filtration efficiency is 95.70%,and the pressure drop is 46 Pa.After calcination at 1200?,alumina inorganic nanofibers with diameters of 163±11 nm and 195±26 nm were obtained.(3)Using PSA and B as raw materials,PSA-B composite nanofiber membrane was prepared by electrospinning technology.When the amount of bromide was 2.0 wt%,the PM2.5filtration efficiency of PSA-B nanofiber membrane was almost 100%,and the pressure drop was 166 Pa.At the same time,after the high temperature of 200?,1.0 mol/L hydrochloric acid,0.5 mol/L sodium hydroxide treatment for 1 h,PSA-B nanofiber showed good thermal stability,acid and alkali resistance,and the filtration efficiency did not decrease significantly,can be used in the field of high temperature filtration.