Publication: Preparation and characterization of PVDF-HFP copolymer hollow fiber membranes for membrane distillation
Loading...
Official URL
Full text at PDC
Publication Date
2009-09-15
Authors
Advisors (or tutors)
Editors
Journal Title
Journal ISSN
Volume Title
Publisher
Elsevier Science Bv
Citations
Exportar
Abstract
Poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) hollow fiber membranes were prepared by the dry/wet spinning technique at different copolymer concentrations from 17 to 24 wt%. All the spinning parameters were kept constant except the copolymer concentration. The temperature of both the internal and external coagulants was maintained at 40 degrees C. The effects of the copolymer concentration on the morphological properties of the hollow fibers were studied in terms of external and internal diameter and scanning electron microscopy (SEM). It was found that the thickness of all tested hollow fibers did not change significantly. An evolution of the cross-section structure with the increase of the copolymer concentration was detected. The cross-section of the hollow fiber prepared with the lowest copolymer concentration exhibited a finger-like structure in both the external and internal layers disappearing in the internal layer as the copolymer concentration increases. Finally, a spongelike structure is formed through all cross-section of the hollow fiber prepared with the highest concentration. This may be explained based on the decrease of the coagulation rate with the increase of the copolymer concentration in the dope solution.
Description
© 2009 Elsevier B.V. Engineering with Membranes Conference (2008. Vale do Lobo, Algarve, Portugal). The author (M. Essalhi) is thankful to the Middle East Desalination Research Centre for the grant that partially supported this study (REF. 06-AS007). The financial support of the Spanish Ministry of Science and Education (MEC) (Project FIS2006-05323) is acknowledged.
UCM subjects
Unesco subjects
Keywords
Citation
[1] C. Feng, R. Wang, B. Shi, G. Li and Y. Wu, Factors affecting pore structure and performance of poly(vinylidene fluoride-co-hexafluoropropylene) asymmetric porous membrane, J. Membr. Sci., 277 (2006) 55–64.
[2] M.S. El-Bourawi, Z. Ding, R. Ma and M. Khayet, A framework for better understanding membrane distillation separation process, J. Membr. Sci., 285 (2006) 4–29.
[3] M. Khayet and T. Matsuura, Application of surface modifying macromolecules for the preparation of membranes for membrane distillation, Desalination, 158 (2003) 51–56.
[4] M. Khayet, The effects of air gap length on the internal and external morphology of hollow fiber membranes, Chem. Eng. Sci., 58 (2003) 3091–3104.
[5] L. Shi, R. Wang, Y. Cao, C. Feng, D.T. Liang and J.H. Tay, Fabrication of poly(vinylidene fluorideco-hexafluoropropylene) (PVDF–HFP) asymmetric microporous hollow fiber membranes, J. Membr. Sci., 305 (2007) 215–225.
[6] L. Shi, R. Wang, Y. Cao, D.T. Liang and J.H. Tay, Effect of additives on the fabrication of poly(vinylidene fluoride-co-hexafluropropylene) (PVDF–HFP) asymmetric microporous hollow fiber membranes, J. Membr. Sci., 315 (2008) 195–204.
[7] M.A. Izquierdo Gil, M.C. García Payo, C. Fernández Pineda, Direct contact membrane distillation of sugar aqueous solutions, Sep. Sci. Technol. 34 (1999) 1773–1801.
[8] K.C. Khulbe, C.Y. Feng, F. Hamad, T. Matsuura, M. Khayet, Structural and performance study of micro porous polyetherimide hollow fiber membranes prepared at different air gap, J. Membr. Sci. 245 (2004) 191–198.