Functionalized Nonwovens For Portable Water Purification Devices And Their Sterilization Properties

Some people such as workers,travelers,field explorers and soldiers,may need to fetch drinking water when they are be outdoors.But the water may contain pathogenic microorganisms and can’t be directly drunk.A serious of functional nonwoven filter materials used in the adsorption ultrafiltration water purification device were fabricated in this paper,which can specifically remove microorganisms in water as the filter medium.Polypropylene(PP)nonwoven fabric with three-dimensional network structure and micron-sized pores is selected as the substrate.The functional groups are introduced onto the PP surface via UV-initiated grafting and electrospinning.The nonwoven filter material with quaternary amine cationic functional group(PPDMAEMA-QA)and sulfonic anion functional group(PP-GMA-SS),and polyvinyl alcohol(PVA)/Chitosan(CS)/quaternary functional non-woven material PVA/CS/(PPDMAEMA-QA)were prepared.In this paper,the removal performance and removal mechanism of functional nonwoven materials for microorganisms in natural water were also researched.The functional nonwoven materials for water purification modified by quaternary ammonium groups and sulfonic acid groups via UV graft polymerization.The removal performance of microorganisms in natural water by the functional nonwoven materials was studied by batch experiments.The results showed that the functional materials exhibited the better sterilization effect on removing microorganisms for low bacterial content of water at low flow rates.When the filtration flow rate is 15 m L/min,the 10 filtering layers of PP-DMAEMA-QA has the best sterilization performance for 1000CFU/m L of water,and the sterilization rate is stable at about 93%.The PP-DMAEMA-QA nonwoven fabric as a supporting layer was coated with the electro-spinning of polyvinyl alcohol(PVA)and chitosan(CS)fiber.The PVA/CS/(PP-DMAEMA-QA)was obtained to remove microorganisms in the research.The performance of the composite material PVA/CS/(PP-DMAEMA-QA)prepared under different spinning process conditions was discussed.The results showed that the composite material prepared with 8wt% polyvinyl alcohol,1.6wt% chitosan,21 k V spinning voltage,and 0.11 mm/min injection speed has the better sterilization performance.The sterilization performance of 10 layers of composite material can reach 99.7%.The material can be used as the adsorption filtration part of the portable water purification device.It can also help to avoid or alleviate the pollution of membrane unit and decrease the filtration performance of the water purification device.An integrated water purification device is designed by combining functional nonwoven materials with hollow fiber membrane,which can be used to purify surface water for drinking.This study showed that the purification effect by the device can meet the drinking water sanitation standards,and the water quality is safe and stable.