371:
291:
279:
303:
267:
420:
476:
163:-salt membranes, and hollow-fiber contained liquid membranes. Liquid membranes have been extensively studied but thus far have limited commercial applications. Maintaining adequate long-term stability is a key problem, due to the tendency of membrane liquids to evaporate, dissolve in the phases in contact with them, or creep out of the membrane support.
46:, is a synthetically created membrane which is usually intended for separation purposes in laboratory or in industry. Synthetic membranes have been successfully used for small and large-scale industrial processes since the middle of the twentieth century. A wide variety of synthetic membranes is known. They can be produced from
439:
One of the critical characteristics of a synthetic membrane is its chemistry. Synthetic membrane chemistry usually refers to the chemical nature and composition of the surface in contact with a separation process stream. The chemical nature of a membrane's surface can be quite different from its bulk
171:
Polymeric membranes lead the membrane separation industry market because they are very competitive in performance and economics. Many polymers are available, but the choice of membrane polymer is not a trivial task. A polymer has to have appropriate characteristics for the intended application. The
603:
applications. There is some controversy in defining a "membrane pore". The most commonly used theory assumes a cylindrical pore for simplicity. This model assumes that pores have the shape of parallel, nonintersecting cylindrical capillaries. But in reality a typical pore is a random network of the
540:
Synthetic membranes can be also categorized based on their structure (morphology). Three such types of synthetic membranes are commonly used in separation industry: dense membranes, porous membranes, and asymmetric membranes. Dense and porous membranes are distinct from each other based on the size
523:
phenomena. In most membrane separation processes (especially bioseparations), higher surface hydrophilicity corresponds to the lower fouling. Synthetic membrane fouling impairs membrane performance. As a consequence, a wide variety of membrane cleaning techniques have been developed. Sometimes
176:
for separated molecules (as in the case of biotechnology applications), and has to withstand the harsh cleaning conditions. It has to be compatible with chosen membrane fabrication technology. The polymer has to be a suitable membrane former in terms of its chains rigidity, chain interactions,
322:
by the addition of highly acidic or basic functional groups, e.g. sulfonic acid and quaternary ammonium, enabling the membrane to form water channels and selectively transport cations or anions, respectively. The most important functional materials in this category include
66:, and production method. The chemical and physical properties of synthetic membranes and separated particles as well as separation driving force define a particular membrane separation process. The most commonly used driving forces of a membrane process in industry are
541:
of separated molecules. Dense membrane is usually a thin layer of dense material utilized in the separation processes of small molecules (usually in gas or liquid phase). Dense membranes are widely used in industry for gas separations and reverse osmosis applications.
197:
temperatures), affecting the membrane performance characteristics. The polymer has to be obtainable and reasonably priced to comply with the low cost criteria of membrane separation process. Many membrane polymers are grafted, custom-modified, or produced as
78:. Synthetic membranes utilized in a separation process can be of different geometry and flow configurations. They can also be categorized based on their application and separation regime. The best known synthetic membrane separation processes include
406:
or some glassy materials). By contrast with polymeric membranes, they can be used in separations where aggressive media (acids, strong solvents) are present. They also have excellent thermal stability which make them usable in high temperature
440:
composition. This difference can result from material partitioning at some stage of the membrane's fabrication, or from an intended surface postformation modification. Membrane surface chemistry creates very important properties such as
528:, and the membrane needs to be replaced. Another feature of membrane surface chemistry is surface charge. The presence of the charge changes the properties of the membrane-liquid interface. The membrane surface may develop an
158:
Liquid membranes refer to synthetic membranes made of non-rigid materials. Several types of liquid membranes can be encountered in industry: emulsion liquid membranes, immobilized (supported) liquid membranes, supported
616:, temperature, and storing time in solution. The thicker porous membranes sometimes provide support for the thin dense membrane layers, forming the asymmetric membrane structures. The latter are usually produced by a
146:. Even though ceramic membranes have a high weight and substantial production costs, they are ecologically friendly and have long working life. Ceramic membranes are generally made as monolithic shapes of tubular
503:(pore) intrusion behavior. Degree of membrane surface wetting is determined by the contact angle. The surface with smaller contact angle has better wetting properties (θ=0°-perfect wetting). In some cases low
862:
Martinez F., Martin A., Pradanos P., Calvo J.I., Palacio L.., Hernandez A. Protein adsorption and deposition onto microfiltration membranes: the role of solute-solid interactions. J.
142:
oxide. Ceramic membranes are very resistant to the action of aggressive media (acids, strong solvents). They are very stable chemically, thermally, and mechanically, and biologically
739:
Mutch, Greg A.; Qu, Liu; Triantafyllou, Georgios; Xing, Wen; Fontaine, Marie-Laure; Metcalfe, Ian S. (28 May 2019). "Supported molten-salt membranes for carbon dioxide permeation".
483:
The contact angle is determined by solving the Young's equation for the interfacial force balance. At equilibrium three interfacial tensions corresponding to solid/gas (γ
869:
Palacio L., Ho C., Pradanos P., Calvo J.I, Kherif G., Larbot A., Hernandez A. Fouling, structure and charges of composite inorganic microfiltration membrane. J.
110:
Synthetic membrane can be fabricated from a large number of different materials. It can be made from organic or inorganic materials including solids such as
612:
structure polymers. The structure of porous membrane is related to the characteristics of the interacting polymer and solvent, components concentration,
704:
San Román, M. F.; Bringas, E.; Ibañez, R.; Ortiz, I. (January 2010). "Liquid membrane technology: fundamentals and review of its applications".
575:
of a polymer solution. The membrane structure of a dense membrane can be in a rubbery or a glassy state at a given temperature depending on its
331:, that are at the heart of many technologies in water treatment, energy storage, energy generation. Applications within water treatment include
356:
876:
Templin T., Johnston D., Singh V., Tumbleson M.E., Belyea R.L. Rausch K.D. Membrane separation of solids from corn processing streams.
841:
Jacob J., Pradanos P., Calvo J.I, Hernandez A., Jonsson G. Fouling kinetics and associated dynamics of structural modifications.
568:
460:(in case of bioseparations). Hydrophilicity and hydrophobicity of membrane surfaces can be expressed in terms of water (liquid)
579:. Porous membranes are intended on separation of larger molecules such as solid colloidal particles, large biomolecules (
130:
solids (polymeric mixtures, mixed glasses), and liquids. Ceramic membranes are produced from inorganic materials such as
17:
604:
unevenly shaped structures of different sizes. The formation of a pore can be induced by the dissolution of a "better"
352:
328:
290:
608:
into a "poorer" solvent in a polymer solution. Other types of pore structure can be produced by stretching of
344:
127:
119:
924:
576:
914:
883:
Zydney A. L., Ho C. Effect of
Membrane Morphology on System Capacity During Normal Flow Microfiltration.
512:
32:
529:
340:
324:
278:
553:
253:
249:
99:
495:) interfaces are counterbalanced. The consequence of the contact angle's magnitudes is known as
71:
532:
and induce the formation of layers of solution particles which tend to neutralize the charge.
511:
solutions are used to enhance wetting of non-wetting membrane surfaces. The membrane surface
319:
468:
membrane surfaces have a contact angle in the range of 0°<θ<90° (closer to 0°), where
713:
63:
370:
302:
8:
919:
629:
572:
564:
408:
28:
897:
Ho C., Zydney A. Protein fouling of asymmetric and composite microfiltration membranes.
717:
266:
79:
423:
Contact angle of a liquid droplet wetted to a rigid solid surface.Young's equation: γ
27:
This article is about synthetic membranes for separation. For natural structures, see
453:
399:
257:
229:
203:
182:
173:
59:
855:
Madaeni S.S. The effect of large particles on microfiltration of small particles J.
748:
721:
613:
457:
395:
383:
194:
178:
143:
47:
54:
materials. Most commercially utilized synthetic membranes in industry are made of
600:
596:
592:
525:
504:
403:
336:
332:
190:
135:
95:
91:
87:
83:
202:
to improve their properties. The most common polymers in membrane synthesis are
445:
441:
207:
908:
549:
461:
360:
245:
890:
Ripperger S., Schulz G. Microporous membranes in biotechnical applications.
449:
348:
241:
609:
515:(and related hydrophilicity/hydrophobicity) influences membrane particle
469:
465:
218:
147:
752:
617:
591:) and cells from the filtering media. Porous membranes find use in the
516:
508:
199:
75:
725:
557:
545:
500:
387:
237:
233:
222:
211:
186:
139:
131:
55:
51:
580:
67:
824:, Principles and Applications., New York: Marcel Dekker, Inc,1996.
786:, Principles and Applications., New York: Marcel Dekker, Inc,1996.
605:
520:
496:
391:
225:
123:
115:
419:
560:
214:
160:
111:
703:
475:
359:(AEMFCs), and both the osmotic- and electrodialysis-based
343:. Applications within energy storage include rechargeable
588:
584:
848:
Van Reis R., Zydney A. Bioprocess membrane technology.
738:
74:. The respective membrane process is therefore known as
185:
of its functional groups. The polymers can range form
98:, removal of microorganisms from dairy products, and
472:
materials have θ in the range of 90°<θ<180°.
452:, membrane chemical or thermal resistance, binding
50:materials such as polymers and liquids, as well as
706:Journal of Chemical Technology & Biotechnology
499:phenomena, which is important to characterize the
58:structures. They can be classified based on their
906:
831:, Kluwer Academic Publishers, Netherlands, 1996.
351:. Applications within energy generation include
313:
105:
552:structures. Polymeric dense membranes such as
448:(related to surface free energy), presence of
318:Polymer membranes may be functionalized into
172:polymer sometimes has to offer a low binding
90:of natural gas, removal of cell particles by
357:alkaline anion-exchange membrane fuel cells
31:. For other uses of the term membrane, see
474:
418:
369:
829:Basic Principles of Membrane Technology
14:
907:
544:Dense membranes can be synthesized as
535:
166:
815:Perry’s Chemical Engineers’ Handbook
810:, New York: Marcel Dekker, Inc,1992.
782:Zeaman, Leos J., Zydney, Andrew L.,
692:Perry’s Chemical Engineers’ Handbook
674:, New York: Marcel Dekker, Inc,1992.
414:
378:
193:structures (can also have different
820:Zeman, Leos J., Zydney, Andrew L.,
801:Membrane Formation and Modification
778:
776:
774:
772:
770:
768:
766:
764:
762:
686:
684:
682:
680:
666:
664:
662:
660:
658:
650:Membrane Formation and Modification
353:proton-exchange membrane fuel cells
153:
24:
822:Microfiltration and Ultrafitration
784:Microfiltration and Ultrafitration
25:
936:
642:
456:for particles in a solution, and
329:alkaline anion-exchange membranes
817:,7th edition, McGraw-Hill, 1997.
759:
741:Journal of Materials Chemistry A
694:,7th edition, McGraw-Hill, 1997.
677:
655:
301:
289:
277:
265:
808:Membrane Science and Technology
672:Membrane Science and Technology
620:of dense and porous membranes.
345:metal-air electrochemical cells
732:
697:
296:Polytetrafluoroethylene (PTFE)
13:
1:
793:
314:Polymer electrolyte membranes
577:glass transition temperature
507:liquids such as alcohols or
106:Membrane types and structure
7:
799:Pinnau, I., Freeman, B.D.,
648:Pinnau, I., Freeman, B.D.,
623:
374:Ceramic multicanal elements
10:
941:
563:are usually fabricated by
26:
838:, Springer, Germany, 2006
813:Perry, R.H., Green D.H.,
806:Osada, Y., Nakagawa, T.,
690:Perry, R.H., Green D.H.,
670:Osada, Y., Nakagawa, T.,
325:proton-exchange membranes
33:Membrane (disambiguation)
635:
530:electrokinetic potential
341:reversed electrodialysis
880:. 97(2006): 1536–1545.
554:polytetrafluoroethylene
402:oxides, recrystallised
254:polyvinylidene fluoride
250:polytetrafluoroethylene
901:. 40(2001): 1412–1421.
873:. 138(1998): 291–299.
480:
436:
375:
320:ion-exchange membranes
72:concentration gradient
866:. 221(2000): 254–261.
845:. 138(1997): 173–183.
478:
422:
373:
347:and various types of
887:. 83(2003): 537–543.
491:), and liquid/gas (γ
925:Membrane technology
859:. 8(2001): 143–148.
852:. 297(2007): 16–50.
747:(21): 12951–12973.
718:2010JCTB...85....2S
630:Membrane technology
565:compression molding
536:Membrane morphology
409:membrane operations
390:materials (such as
167:Polymeric membranes
40:artificial membrane
29:Biological membrane
18:Artificial membrane
915:Chemical equipment
885:Biotechnol, Bioeng
836:Sterile Filtration
834:Jornitz, Maik W.,
753:10.1039/C9TA01979K
487:), solid/liquid (γ
481:
479:Wetting of a leaf.
437:
376:
308:Polypropylene (PP)
230:polyacrilonitrile
217:(CA, CN, and CE),
80:water purification
62:, bulk structure,
44:synthetic membrane
899:Ind Eng Chem Res
894:. 1(1986): 43–49.
726:10.1002/jctb.2252
415:Surface chemistry
384:Ceramic membranes
379:Ceramic membranes
284:Polyethylene (PE)
258:polyvinylchloride
204:cellulose acetate
60:surface chemistry
16:(Redirected from
932:
843:J. Coll and Surf
787:
780:
757:
756:
736:
730:
729:
701:
695:
688:
675:
668:
653:
646:
614:molecular weight
458:biocompatibility
305:
293:
281:
272:Polysulfone (PS)
269:
195:glass transition
179:stereoregularity
154:Liquid membranes
21:
940:
939:
935:
934:
933:
931:
930:
929:
905:
904:
864:Coll Interf Sci
796:
791:
790:
781:
760:
737:
733:
702:
698:
689:
678:
669:
656:
647:
643:
638:
626:
597:ultrafiltration
593:microfiltration
569:solvent casting
538:
505:surface tension
494:
490:
486:
434:
430:
426:
417:
404:silicon carbide
381:
337:electrodialysis
333:reverse osmosis
316:
309:
306:
297:
294:
285:
282:
273:
270:
191:semicrystalline
169:
156:
136:silicon carbide
108:
96:ultrafiltration
92:microfiltration
88:dehydrogenation
84:reverse osmosis
36:
23:
22:
15:
12:
11:
5:
938:
928:
927:
922:
917:
903:
902:
895:
892:Bioprocess Eng
888:
881:
874:
867:
860:
853:
846:
839:
832:
825:
818:
811:
804:
795:
792:
789:
788:
758:
731:
696:
676:
654:
640:
639:
637:
634:
633:
632:
625:
622:
537:
534:
492:
488:
484:
446:hydrophobicity
442:hydrophilicity
432:
428:
427:∙cos θ+ γ
424:
416:
413:
386:are made from
380:
377:
315:
312:
311:
310:
307:
300:
298:
295:
288:
286:
283:
276:
274:
271:
264:
208:Nitrocellulose
168:
165:
155:
152:
107:
104:
9:
6:
4:
3:
2:
937:
926:
923:
921:
918:
916:
913:
912:
910:
900:
896:
893:
889:
886:
882:
879:
875:
872:
871:Coll and Surf
868:
865:
861:
858:
854:
851:
847:
844:
840:
837:
833:
830:
826:
823:
819:
816:
812:
809:
805:
802:
798:
797:
785:
779:
777:
775:
773:
771:
769:
767:
765:
763:
754:
750:
746:
742:
735:
727:
723:
719:
715:
711:
707:
700:
693:
687:
685:
683:
681:
673:
667:
665:
663:
661:
659:
651:
645:
641:
631:
628:
627:
621:
619:
615:
611:
607:
602:
598:
594:
590:
586:
582:
578:
574:
570:
566:
562:
559:
555:
551:
550:heterogeneous
547:
542:
533:
531:
527:
522:
518:
514:
510:
506:
502:
498:
477:
473:
471:
467:
463:
462:contact angle
459:
455:
451:
447:
443:
421:
412:
410:
405:
401:
397:
393:
389:
385:
372:
368:
366:
362:
361:osmotic power
358:
354:
350:
346:
342:
338:
334:
330:
326:
321:
304:
299:
292:
287:
280:
275:
268:
263:
262:
261:
259:
255:
251:
248:(PE and PP),
247:
246:polypropylene
243:
239:
235:
231:
227:
224:
220:
216:
213:
209:
205:
201:
196:
192:
188:
184:
180:
175:
164:
162:
151:
149:
145:
141:
137:
133:
129:
128:heterogeneous
125:
121:
117:
113:
103:
101:
97:
93:
89:
85:
81:
77:
73:
69:
65:
61:
57:
53:
49:
45:
41:
34:
30:
19:
898:
891:
884:
878:Biores Tech
877:
870:
863:
856:
849:
842:
835:
828:
821:
814:
807:
803:, ACS, 1999.
800:
783:
744:
740:
734:
709:
705:
699:
691:
671:
652:, ACS, 1999.
649:
644:
543:
539:
526:irreversible
482:
450:ionic charge
438:
382:
367:generation.
364:
349:flow battery
317:
242:polyethylene
170:
157:
109:
43:
39:
37:
827:Mulder M.,
712:(1): 2–10.
610:crystalline
524:fouling is
513:free energy
470:hydrophobic
466:Hydrophilic
365:blue energy
219:polysulfone
148:capillaries
120:homogeneous
920:Filtration
909:Categories
794:References
618:lamination
517:adsorption
509:surfactant
355:(PEMFCs),
200:copolymers
76:filtration
64:morphology
850:J Mem Sci
558:cellulose
546:amorphous
501:capillary
388:inorganic
238:polyimide
234:polyamide
223:polyether
212:cellulose
187:amorphous
140:zirconium
132:aluminium
56:polymeric
52:inorganic
624:See also
601:dialysis
581:proteins
573:spraying
454:affinity
400:zirconia
256:(PVDF),
252:(PTFE),
183:polarity
174:affinity
134:oxides,
124:polymers
116:ceramics
100:dialysis
68:pressure
857:Por Mat
714:Bibcode
606:solvent
521:fouling
497:wetting
396:titania
392:alumina
260:(PVC).
232:(PAN),
228:(PES),
226:sulfone
122:films,
48:organic
599:, and
571:, and
561:esters
339:, and
221:(PS),
215:esters
210:, and
181:, and
161:molten
138:, and
112:metals
636:Notes
144:inert
42:, or
556:and
327:and
244:and
189:and
94:and
70:and
749:doi
722:doi
589:RNA
585:DNA
548:or
519:or
464:θ.
444:or
431:= γ
363:or
38:An
911::
761:^
743:.
720:.
710:85
708:.
679:^
657:^
595:,
587:,
583:,
567:,
493:LG
489:SL
485:SG
433:SG
429:SL
425:LG
411:.
398:,
394:,
335:,
240:,
236:,
206:,
150:.
126:,
118:,
114:,
102:.
86:,
82:,
755:.
751::
745:7
728:.
724::
716::
435:.
35:.
20:)
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.