Polyelectrolvte Complexes Hollow Fiber Membrane For Fusel Oils Pervaporation Dehydration Processes

The problems of energy shortage and environmental pollution have become increasingly serious.The development and utilization of renewable energy are gaining more and more attention.Fusel oils(by-product of alcohol fermentation)are an important and renewable energy source for biofuels.Its low energy consumption,clean and efficient separation and utilization are the hot topics in this field.Fusel oils can be isolated and processed many important fine chemical products.For example,isoamyl alcohol from fusel oils is an important raw material for synthetic perfumes and neutral liquid crystal materials.So the dehydration of fusel oils is necessary to achieve its comprehensive development and utilization.Pervaporation is a highly efficient and energy-saving membrane separation technology,suitable for the separation of azeotropic mixed system.In this study,based on the design of membrane structure and material,the in situ hybridization and sulfonation were used.The separation selectivity,permeation flux and long-term operation stability of the PEC hollow fiber pervaporation membrane in the organic dehydration are improved.First of all,polyelectrolyte complexes/silica(PEC/SiO2)hybrid hollow fiber membranes were prepared in situ via sol-gel process on polysulfone ultrafiltration support membrane.?-glycidyloxypropyltrimethoxysilane(GPTMS)was introduced as precursor and crosslinker into poly(diallyldimethylammonium chloride)-sodium carboxymethyl cellulose complexes to form SiO2 particles in situ and enhance the interaction between inorganic and organic components.When the loading of GPTMS is less than 10 wt%,the in-situ SiO2 particles are uniformly dispersed in the PEC matrix,creating a mass transfer interface that imparts better pervaporation to the hybrid membrane.PEC/SiO2 membrane(PECM/SiO2)achieved an enhanced flux compared with the PEC pristine membrane without GPTMS.The membranes possessed a flux of 1332 g/m2h and water content in permeate of 99.0 wt%for the dehydration of fusel oils at 60 ?.Furthermore,the performance of PECM/SiO2 for the batch continuous dehydration application of fusel oils was more efficient than PERVAP-1001 commercial membranes.After a continuous operation of the hybrid membrane,the organics content in feed can be increased from 90.0 wt%to 99.0 wt%.Furthermore,a large number of sulfate groups are introduced into PEC by sulfonation method to prepare polyelectrolyte complex pervaporation membranes with negatively charges.By adjusting the dosage ratio of sulfonated reagent,the pervaporation membrane(SPECM)with high degree of sulfonation is obtained.By this method,the hydrophilicity of the membrane is improved and the contact angle reaches 13�.The flux and permeate water content are 1354 g/m2h and 99.35 wt%for the dehydration of 90.0 wt%ethanol water mixture at 60 ?.On this basis,in order to study its feasibility in industrial application,the membrane was crosslinked by GPTMS.The crosslinked membrane remained stable under high water-content,which broadens its practicability and stability under different operating conditions.The membranes possessed a flux of 1493 g/m2h and water content in permeate of 99.3 wt%for the dehydration of fusel oils at 60 ?.After a continuous operation of 36 hours,the organics content in feed can be increased from 90.0 wt%to 99.0 wt%in the 1000g fusel oils at 50 ?.Moreover,the flux and separation performance of SPECM were better than that of the hybrid membrane in the continuous operation.The flux is always more than 1.3 times that of the hybrid membrane.The water content in permeate is also maintained at above 98.5wt%.In this study,the in situ hybridization and sulfonation were used to prepare high performance hollow fiber membranes,which were potentially applied in fusel oils pervaporation dehydration processes.